SpaceX

SpaceX's Falcon 9 rocket sits on its launch pad at Cape Canaveral Air Force Station during Monday's pre-launch engine test. The rocket is due to loft a Dragon cargo capsule to the International Space Station on Friday.

The commercial SpaceX rocket venture says it's resolved the problems that cropped up during last October's cargo run to the International Space Station, and all systems are go for the delivery mission due for launch on Friday.

"We're a launch company," SpaceX President Gwynne Shotwell said during a pre-launch briefing at NASA's Kennedy Space Center in Florida on Thursday. "We love to launch."

SpaceX's Falcon 9 rocket is due to lift off from Space Launch Complex 40 at Cape Canaveral Air Force Station at 10:10 a.m. ET Friday. Forecasters said there was an 80 percent chance of acceptable weather for an on-time launch, with only a minor concern about the potential for thick cloud cover.

This will mark the third launch of an unmanned SpaceX Dragon cargo capsule to the space station. It's the second cargo delivery under the terms of a $1.6 billion, 12-flight resupply contract with NASA. And it's the first time that a payload has been carried in the Dragon's unpressurized "trunk."

The trunk is an extra cargo space sitting beneath the Dragon's pressurized main compartment. It's basically been empty for the Dragon's previous two launches, in May and October 2012, but this time there'll be an 822-pound (373-kilogram) package containing a new set of grapple bars to be installed onto the station during a later spacewalk. The package will be put into storage using the station's robotic arm during the three weeks that the Dragon is due to be hooked up to the orbital outpost.

Another 1,493 pounds (677 kilograms) will be riding in the pressurized space, Shotwell said. That cargo will include food, clothing and other crew provisions as well as scientific experiments, two freezers for lab samples and spare parts for the station's air-scrubbing system. Unlike last time, there'll won't be any satellites flying as a secondary payload on the Dragon, Shotwell said.

Anomalies addressed
In October, the previous Dragon mission failed to deploy its secondary payload, an Orbcomm communications satellite, because of an engine problem that occurred during the Falcon 9's ascent. Shotwell said the problem was traced to "a material flaw that went undetected" in the sheathing around one of the nine Merlin engines on the Falcon's first stage. The failure of that material resulted in a breach that caused the engine to lose pressure, signaling the rocket's flight computer to shut down the engine.

Despite the engine shutdown, the rocket was able to reach the required altitude for the space station delivery. It couldn't deliver the Orbcomm OG2 satellite to its proper orbit, however. Days later, the satellite fell out of the sky.

Shotwell said the engine assembly for the rocket to be launched on Friday has gone through extensive testing, using a procedure called non-destructive evaluation, or NDE. She said half-jokingly that engineers skilled in NDE procedures were more valued in the wake of last October's anomaly. "We're hiring you at SpaceX," she said.

She also discussed another anomaly that came to light after the previous Dragon's splashdown: The spacecraft sat in Pacific waters off the coast of California for hours, and it turned out that the water may have shorted out the power supply for the research freezer shipped down from the space station. NASA space station manager Mike Suffredini told reporters that the freezer was "fine, even with the loss of power." Since then, the Dragon for Friday's mission has been retrofitted to make the power supply more watertight, Shotwell said.

Suffredini said he was satisfied with the way that SpaceX followed up on the anomalies. "There's nothing that we would have done that they have chosen not to do," he said.

NASA has had its own share of problems crop up: Last week, the space station's main communication system went out for several hours during a software upgrade, but Suffredini said the outage "was never really a big concern." The software was eventually upgraded successfully, he said.

"Over a million lines of code were upgraded, including the software for the [robotic] arm that's going to capture the Dragon," Suffredini said.

A fast flight
The flight plan calls for the Falcon 9 to send the Dragon capsule on an orbital trajectory that will bring it to the station less than 24 hours after launch. That's a significant faster trip than the previous Dragon flights, due to a favorable orbital geometry, Shotwell said. When the Dragon comes within 10 meters (33 feet), astronauts will use the station's robotic arm to latch onto the spacecraft and pull it in for its berthing at a port on the Harmony module. The hatch would be opened on Sunday. Then the astronauts would unload the supplies and fill the Dragon back up with cargo to be returned to Earth.

The Dragon is due to be unberthed on March 25, and will head down to a Pacific splashdown and recovery.

SpaceX's cargo flights are meant to fill the gap left by the retirement of NASA's space shuttle fleet in 2011. Another company, Orbital Science Corp., has a separate NASA contract to begin deliveries to the space station later this year. Cargo can also be delivered to the space station on Russian, Japanese and European transports, but only SpaceX currently has the capability to bring cargo back down.

SpaceX and two other companies, Sierra Nevada Corp. and the Boeing Co., are developing crew-capable spacecraft under a separate NASA program. Those spaceships could be ready for NASA's use as early as 2017. In the meantime, U.S. astronauts have to ride on Russian Soyuz capsules at a cost of about $60 million per seat.

Extra credit:

• The previous mission included a shipment of vanilla-chocolate swirl ice cream for the crew, stored inside a research freezer. This time, the Dragon will be bringing snacks that are "a little bit healthier," Shotwell said. She said the goodies would be coming from the orchard of a SpaceX employee's father — but she wasn't more specific.
• When Shotwell was asked about millionaire space tourist Dennis Tito's plan to send a married couple to Mars and back in 2018, she replied that SpaceX was not currently participating in the mission. "I think his plan is very ambitious," she said. Shotwell didn't slam he door on Tito, however. "We are a launch service provider, and if he can come up with the funding to execute this mission, I'd be happy to have him as a customer," she said.

More about SpaceX:

• Falcon 9 rocket passes pre-launch test
• These space capsules can fit on your desk
• SpaceX's press kit for the March 1 mission

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Millionaire space tourist Dennis Tito and his partners have had to tell questioners repeatedly that they're not "crazy" or "nuts" to think they can launch a man and a woman to Mars and back by 2019 — but if the Inspiration Mars Foundation's "Mission for America" succeeds, it may well be because it's just crazy enough. 

Other private space ventures, ranging from SpaceX to the Golden Spike Company and Planetary Resources, are depending on turning a profit someday through the sale of rocket flights, or missions to the moon, or water and precious metals mined from asteroids. Tito, in contrast, freely admits the 501-day mission is a "one-shot deal" that's unencumbered by a long-range business plan. He's committed to supporting the five-year development effort for the first two years, during which time he and the rest of the team will try to raise the money and perfect the technologies for the three more expensive years to follow.

So how much is that going to cost him? "Who knows?" Tito said.

Tito expects to look in all the usual places for funding, including sponsorships, the sale of media rights, the sale of scientific data from the flight and private contributions. A 6-year-old boy has already sent in one of the first contributions, amounting to $10. "This is my Apollo," he was quoted as saying.

If Tito had a dime for every time the Apollo era was invoked on Wednesday, he'd be making a good start toward a fund-raising goal that is estimated to range around $1 billion. Some questioned whether the non-stop Mars flyby would be worth it, on scientific or economic grounds. But that's missing the point: Like Tito's eight-day trip to the International Space Station in 2001, the payoff would be purely inspirational rather than scientific.

"Inspiration Mars reminds me of Apollo 8 in 1968, going around the moon," software billionaire Charles Simonyi, who spent tens of millions of dollars buying two flights to the International Space Station, said in a Twitter update. "Inspiration is a goal for humans, science should be left to the rovers."

In a follow-up exchange of messages, Simonyi told NBC News that he wouldn't be spending millions more to support Tito's effort. He noted that his philanthropic foundation, the Charles Simonyi Fund for Arts and Sciences, "has spent the $100M it had in 10 years, as planned."

"But I think Inspiration will have broad-based support," he said. "Very exciting."

NASA also voiced moral support, saying in a statement that the Inspiration Mars mission was "a testament to the audacity of America's commercial aerospace industry and the adventurous spirit of America's citizen-explorers." Inspiration Mars plans to pay NASA for access to the agency's know-how about thermal protection systems for re-entry, said Taber MacCallum, the foundation's chief technology officer and a co-founder of Paragon Space Development Corp.

Inspiration Mars

A graphic from Inspiration Mars shows the expected path of a spacecraft going around the far side of Mars during a 501-day round trip launched in 2018.

Technical issues
In addition to the craziness about the money, there's the craziness about thinking that the rocket and crew capsule will be ready to launch on Jan. 5, 2018, when the planets literally align. A launch on or around that date would result in a straightforward, no-fuss trajectory that would come within 100 miles of Mars' backside on Aug. 20, 2018, and bring the spacecraft back to Earth on May 21, 2019. The mission plan is outlined in a feasibility analysis prepared for an aerospace conference, but Tito and his co-authors acknowledge that the space vehicles cited in the paper don't yet exist.

The paper says it'd be feasible to use the still-under-development SpaceX Falcon Heavy rocket and a modified SpaceX Dragon capsule, with a Bigelow-type inflatable module added on. But MacCallum acknowledged that Inspiration Mars was still talking with potential industry partners on what the launch configuration might be. He said choosing that configuration, as well as designing the life-support system and the thermal protection system, were high priorities on the to-do list.

MacCallum stressed that simplicity would be the key. "This is going to be a Lewis and Clark mission to Mars," MacCallum said. "Keep it bare bones, keep it simple."

Tito provided scant details about the five-year development timeline but said that the mission would rely upon technologies developed for flights to the space station. "It uses low-Earth-orbit architecture ... and we're just adapting it in effect to a very large Earth orbit," he said. Responding to questions about the tight time frame, Tito pointed out that Apollo 8's around-the-moon mission took place just a year after the first unmanned test launch of NASA's Saturn 5 rocket in 1967. (However, it took five years to design and develop the Saturn 5 in preparation for that first launch.)

The trajectory for the "Mission for America" is designed such that only minor course corrections would be required along the way. There'd be no engine burn required for the return leg of the trip, and no deorbit burn. However, the spacecraft's speed at re-entry would be 32,000 mph (14.2 kilometers per second), or almost twice as fast as the space shuttle's re-entry speed. And if the trajectory went slightly off for some reason, there's a chance that the capsule could slam into Mars — or miss Earth entirely on the way back, dooming the crew to another deadly circuit. 

Who will go?
Jonathan Clark, a former NASA flight surgeon who has served as an adviser for several space ventures, acknowledged that "there's no question this is a risky and bold endeavor." He estimated that there was a roughly 7 percent chance that one of the two astronauts on board would experience a serious medical issue during the mission. That's the big reason why it'd be a two-person trip rather than a solo flight: so that one of the astronauts could serve as the backup for the other. That, and the fact that it'd be an awfully lonely year and a half for just one astronaut.

Tito insists that the two-person crew should consist of a man and a woman, preferably a married couple, in order to combat the loneliness and reduce the risk of crew incompatibility. Tito joked that one of the mission's media deals might involve Dr. Phil giving "marital advice" to the couple while they're in flight.

Like most of the spacecraft components, the crew would be American, Tito said. He described the key attribute for prospective crew members as "the Right Stuff times 10." MacCallum, meanwhile, said the astronauts would have to have "an amazing mechanical skill" in order to keep the onboard systems running smoothly. MacCallum's wife, Paragon co-founder Jane Poynter, said they'd have to be "even-keeled" to get along for a year and a half while cooped up in the outer-space equivalent of an RV. (MacCallum has said that he and Poynter would be interested in taking the Mars trip themselves.)

Clark estimated that it would take six months to a year to work out the process for crew selection.

Tito faced repeated questions about why he was taking on this mission — and it was clear that American pride was part of the equation. One reporter asked whether Tito merely wanted to get to Mars before the Chinese. "Beat China to Mars?" he replied. "Wouldn't I want to do that? Wouldn't I want America to do that? Wouldn't you want America to do that?"

He also noted that if Inspiration Mars missed the launch opportunity in 2018, the next opportunity for a 501-day mission wouldn't come around again until 2031. "If we don't fly in '18, the next low-hanging fruit is in '31, and we better have our crew trained to recognize other flags," he said. "They're going to be out there."

Update for 8:25 p.m. ET: Tito's plan has also gotten a vote of support from Apollo 11 astronaut Buzz Aldrin, who is writing a book titled "Mission to Mars: My Vision for Exploration." The Washington Post's Brian Vastag quotes Aldrin as saying, "I've talked with Dennis, and I've strongly encouraged him. The purpose is to inspire, to say we're going to do something and then we do it." It doesn't hurt that the schedule calls for the round trip to end two months before the 50th anniversary of the Apollo 11 moon landing.

Update for 9:50 p.m. ET: Here's another vote of support from planetary scientist Alan Stern, president and CEO of the Golden Spike Company: "Very excited about Inspiration Mars and the way they and we at Golden Spike are both breaking the mold in human space exploration in this country — and around the world," Stern wrote in an email. Golden Spike is working on a plan to launch missions to the moon at a cost of $1.4 billion per mission (that's $700 million per seat for a two-person flight). The company is currently in the midst of an Indiegogo crowdfunding campaign. 

More about flights to Mars:

• Married couple wanted for Mars trip
• 500-day mock Mars trip raises problem
• Does Mars need women? Russians say no

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Millionaire space tourist Dennis Tito's plan to send two astronauts on a 501-day flight that zooms past Mars and swings back to Earth would set plenty of precedents on the final frontier — but the most intriguing precedent might have to do with the astronauts that are to be sent: one man and one woman, preferably a married couple beyond childbearing years. We're talking about sex in space, folks.

And if that's not intriguing enough, consider this: There are already a couple of candidates for the job.

"We'll certainly throw our hat in the ring," said Taber MacCallum, who's a member of the development team for the 2018 mission that Tito has in mind.

MacCallum and his wife, Jane Poynter, were crew members together in Biosphere 2, the controversial two-year-long experiment in long-term environmental containment. They went on to become co-founders of Paragon Space Development Corp., a company specializing in life-support systems for spacecraft. Their expertise in life support is why they're involved in Tito's "Mission for America," which was officially unveiled on Wednesday at the National Press Club in Washington. But it just so happens that they also fit the profile for the trip: Poynter is about 50, and MacCallum will turn 49 on July 20, the anniversary of the Apollo 11 moon landing.

The couple won't be the only candidates in the running. "When we tell people we're proposing to send a man and a woman on a mission to Mars, as a married couple, people line up. ... That chord gets struck over and over again," MacCallum said.

Paragon

Taber MacCallum and his wife, Jane Poynter, are part of the planning team for a mission to Mars in 2018. They're also potential candidates to take the trip.

MacCallum explained that Tito wants the crew on humanity's first trip to Mars to be representative of humanity, and because the current concept for the trip calls for two spacefliers, that means a man and a woman. A married couple would be ideal, MacCallum said, because of the "whole issue of companionship." MacCallum didn't refer specifically to sex, but that would presumably be part of the companionship package.

"When you're out that far, and the Earth is a tiny, blue pinpoint, you're going to need someone you can hug," Tito told Space.com. During Wednesday's briefing, Tito told reporters that he envisioned Dr. Phil giving the couple "marital advice" during the trip.

In addition to their experience with life-support systems (and with each other), MacCallum and Poynter can draw upon their experience with life in isolation during the Biosphere 2 experiment in Arizona, which lasted from 1991 to 1993. The isolation inside a two-room spacecraft for 501 days will be even deeper. Even though the Biosphere 2 crew was separated from the outside world, "we could walk out at any time," MacCallum pointed out.

That's not the only challenge: Even with radiation shielding in place, the round trip to Mars is likely to involve exposure levels higher than NASA's limits, MacCallum said. (That's why the astronauts should be beyond their childbearing years and willing to accept an increased risk of cancer.)

Then there's the exposure to the health effects of long-term weightlessness, including bone loss and muscle loss. The astronauts who fly past Mars will surpass Soviet cosmonaut Valery Polyakov's 437-day record for continuous time in microgravity, set in 1994-1995 aboard the much roomier Mir space station. 

"We're definitely pushing boundaries," MacCallum said. "It's definitely going to be hard and challenging. But we can rely on elegance and simplicity."

When, where and how?
The details of the mission plan have come to light just in the past few days, but MacCallum said that Tito has been mulling over the idea for years. Tito started out as an engineer at NASA's Jet Propulsion Laboratory, helping to design trajectories for the Mariner missions to Mars in the 1970s. Then he put his math genius to work in the investment world, building California-based Wilshire Associates into a multibillion-dollar powerhouse. In 2001, he spent around $20 million of his fortune for a seat on the Russian Soyuz spacecraft traveling to and from to the International Space Station.

After his eight-day space tour, Tito got back to business. But he also started working out a trajectory that could send a spaceship directly from Earth to Mars for a fly-by within 100 miles (160 kilometers) of the Red Planet's surface, and then back to the home planet 501 days after launch. Once the spaceship was on its way, only minor course corrections would be needed. There'd be no need for undocking or redocking ... no landing ... no do-or-die engine burn for the return from Mars.

There's one big catch, though: The trip will have to be started when the planets were aligned just right. One opportunity will come in 2016. Then there's another one in 2018. After that, the next chance won't come around until 2031.

Planning for a launch in January 2018 looked particularly attractive, and not just because that could plausibly provide enough time to put the mission together. That's also a time frame when solar activity is expected to be at a minimum, reducing the level of radiation exposure. So Tito assembled a team from Paragon as well as NASA's Ames Research Center and other space ventures to flesh out the mission plan.

The plan calls for launching the two astronauts in a crew capsule with a transfer rocket stage. If the launch vehicle is powerful enough — say, the size of SpaceX's Falcon Heavy — the upper stage and the crew capsule could be launched in one go. If the rocket doesn't have that much oomph, the capsule and the upper stage could be launched separately and then linked up in Earth orbit for the push onward to Mars.

Inspiration Mars

An artist's conception shows how the spacecraft for the Inspiration Mars Foundation's "Mission for America" might be configured — with a crew capsule, an inflatable module similar to the ones built by Bigelow Aerospace, and an attached upper stage that could provide radiation shielding. The actual design has not yet been set.

"We only need to attach the upper stage. There's no need to get rid of it," MacCallum said. In the right configuration, that upper stage could even provide some of the required shielding from solar radiation and heating, he said.

The crew's 600 cubic feet of living space would include a capsule for launch and re-entry, with a well-shielded sleeping quarters that could provide a safe haven if solar storms erupted. There would be a habitat module — perhaps an inflatable module like the one that Bigelow Aerospace has been working on for NASA's use. The main idea is to keep the crew compartment as simple as possible while providing all the necessary amenities for a 501-day trip. "It's a '55 Chevy," MacCallum said.

To test the feasibility of the plan, Tito and his colleagues looked at the specifications for the Falcon Heavy as well as a modified version of SpaceX's Dragon capsule. But MacCallum emphasized that the team was not committed to using SpaceX hardware. He said the idea was getting a "great response" from a variety of aerospace companies. "If this mission is going to happen, they want 'their vehicle' to do it," McCallum said.

How much? And why?
MacCallum characterized the mission as "purely philanthropic," with the aim of inspiring future scientists and engineers as well as bridging the gap in NASA's plans for exploration beyond Earth orbit. NASA's current timetable calls for astronauts to go no farther than the International Space Station until 2021 at the earliest. Even though the Mars-and-back mission wouldn't make any stops, the trip could produce useful scientific data — and an adventure as grand as the Apollo moonshots of the '60s and '70s.

"I think we really need what Apollo did for America, but we didn't realize it while we were doing Apollo," MacCallum said.

Toward that end, Tito set up the Inspiration Mars Foundation. "He has committed to funding the first two years of this development, and he is committed to finding the rest of the money," MacCallum said. "Dennis is already getting tremendous interest in this mission from people of means."

The foundation is also looking into media deals and sponsorships. "Farmers Insurance cut a $700 million deal for the naming rights for a stadium," MacCallum noted. "Wow ... that's a not-insubstantial part of the money that we're talking about."

How much money are we talking about? MacCallum quoted Tito as saying "it's a fraction of what Curiosity cost," with reference to NASA's $2.5 billion robotic mission to Mars. Other reports have put the cost in the range of $1 billion or so — which is far less than the projected price tag for the crewed missions NASA plans to send to Mars in the 2030s.

MacCallum emphasized that Tito's "Mission for America" was meant to support America's space agency, not compete with it. "This mission is only even remotely contemplatable because of all the work that NASA has done on the International Space Station," he said. And NASA is getting something in return: MacCallum said Inspiration Mars is paying NASA for access to thermal protection technologies developed by the space agency.

Even if MacCallum and Poynter aren't picked to go on the flight, it sounds as if they'll be having the adventure of their lives over the next five years. "I feel so thrilled every day to be working with these people," MacCallum said. "It's just fabulous."

More about sex, Mars and spaceflight:

• Outer-space sex carries complications
• How a TV show could create a Mars colony
• Astronauts could survive Mars radiation

Is Dennis Tito's idea crazy? Check out this follow-up posting for a reality check.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

The meteor that blew up over the Russian city of Chelyabinsk 11 days ago has provided a new focus for the effort to establish an international asteroid warning system, one of NASA's top experts on the issue says.

Lindley Johnson, the executive for the Near Earth Object Observation Program at NASA Headquarters in Washington, said that the Feb. 15 impact is certain to become "by far the best-documented meteor and meteorite in history" — but at the time, he and his colleagues could hardly believe it was happening.

"Our first reaction was, 'This can't be. ... This must be some test of a missile that's gone awry,'" Johnson told NBC News.

The Chelyabinsk meteor exploded at an estimated altitude of 12 miles (20 kilometers) over the city of 1.1 million in Russia's Urals Mountains, setting off a shock wave that blew out windows, caused an estimated $33 million in property damage and injured more than 1,200 people.

It was doubly coincidental for Johnson and his colleagues: The meteor was thought to have been caused by the breakup of a 17-meter-wide (55-foot-wide), 10,000-ton asteroid that entered Earth's atmosphere and released the equivalent of 500 kilotons of TNT in explosive energy. All this happened just hours before a 45-meter-wide (150-foot-wide) asteroid, capable of setting off a city-killing blast, passed within 17,200 miles (27,680 kilometers) of our planet. Adding to that coincidence, researchers from around the world were gathered in Vienna for talks aimed at moving forward with an international network to deal with ... asteroid threats!

The spectacle in Russia "certainly brought renewed interest to our efforts here," said Johnson, a leader of NASA's delegation to the Vienna talks.

He said the recommendations from the researchers were "well-received" and are moving up the ladder to the next phase in a U.N.-led process for addressing outer-space threats. An action plan could be considered by the U.N. Committee on the Peaceful Uses of Outer Space during its next meeting in Vienna in June.

Johnson summarized the three main points of the recommendations:

• Set up an international asteroid warning network, or IAWN, supported with existing detection assets but incorporating additional contributions. "The basis of such a network already exists," Johnson said, thanks to NASA, the European Space Agency, the International Astronomical Union's Minor Planet Center and the NEODyS asteroid-tracking center at the University of Pisa in Italy. NASA also has partnered with the U.S. Air Force to share tracking data about near-Earth objects. Just this week, a $25 million Canadian-built satellite known as NEOSSat was launched to look for small asteroids in Earth-threatening orbits.
• Bring the world's space agencies together in a new working group called the Space Mission Planning and Advisory Group — also known as SMPAG (pronounced like "Same Page"). The group's purpose, Johnson said, would be to "get all the agencies on the 'same page' as far as assessing what capabilities could be brought to bear should there be a threatening asteroid detected."
• Put asteroid experts in contact with countries around the world, to advise disaster response agencies about the nature of a potential impact event — that is, the area expected to be affected, the potential effects and the scale of the evacuation if necessary. "It's an offshoot of the warning network," Johnson said. If the asteroid behind the Russian meteor had been detected in advance, for example, the expert network might have advised emergency workers about the potential for a midair blast and the resulting shock wave (although Johnson said he was "surprised" by the shock wave's effect).

Until last year, NASA spent about $4 million a year to track near-Earth objects, or NEOs, and Johnson said the program "has accomplished quite a bit in the relatively short time that it's been in existence." About 95 percent of the potentially threatening asteroids bigger than a kilometer (half-mile) wide have been detected. However, now NASA is working on charting the asteroids down to a width of 100 meters (330 feet). To fund that more difficult task, the annual funding level for NEO research was raised to $20 million a year.

NASA is using that money to beef up its capabilities for spotting smaller asteroids, through programs such as the Asteroid Terrestrial-impact Last Alert System, or ATLAS, which is due to get $5 million over the next five years. Less than a million dollars a year is going toward studies aimed at figuring out what to do if a threatening asteroid is found, Johnson said. After all, you have to identify the risky rocks before you can do anything about them. The potential strategies range from diverting it gently with the aid of gravity tractors or space paintball guns, to blasting it with nukes, Bruce Willis-style.

"It really depends on the scenario that we'd be faced with," Johnson said. "It depends on how big the object is. It depends on how long we have to do something about it. And if we do the search-and-detection job right, we will find a potential hazard many years if not decades before it becomes an immediate threat. There may be technologies available at that time that we never thought about. I don't get too worked up about trying to find an immediate technology that we've got to have right now to do that. Our focus is to find them as early as we can, and have the maximum amount of time to do something about it."

Update for 7:30 p.m. ET Feb. 26: Looking for a practical tip? The large majority of the people injured by the meteor blast were hurt by flying glass, which led Johnson to give this advice during a Vienna news conference: "When you see a white flash and a large trail in the sky, it's probably not a good time to stand at the window and look at it, because it may be a blast coming."

Update for 8:15 p.m. ET Feb. 26: As reported in Technology Review's Physics arXiv Blog, Colombian researchers used video from dashboard cameras and other sources to reconstruct the orbital path of the Russian meteor — and they classified it as an Apollo asteroid, a type of space rock whose path crosses Earth's orbit. That's consistent with NASA's analysis, which said the asteroid traced an orbit that ranged between the main asteroid belt and the region of outer space inside Earth's orbit.

"The preliminary orbit indicates it takes about 2.1 years to go around the sun once ... so this thing was out at its farthest distance from the sun roughly a year ago," Bill Cooke, head of the Meteoroid Environments Office at NASA's Marshall Space Flight Center, told reporters during a Feb. 15 teleconference.

The space rock was on its way back out toward the main asteroid belt, coming from Earth's sunward side, when it entered the atmosphere and blew up. That's why it wasn't possible to predict the impact in advance: At a width of 55 feet, the object was too small to show up in traditional sky surveys, and it would have been lost in the sun's glare during its final approach.

So far, searchers have recovered just bits and pieces of the shattered space boulder. "The largest I've heard is a kilogram and a half," or about three pounds, Johnson told NBC News. 

Slideshow: Meteor streaks over Siberia

Yekaterina Pustynnikova / Chelyabinsk.ru via AP

Click through scenes from Russia's Chelyabinsk region, where a huge meteor fireball set off alarms, injured hundreds of people and caused a factory roof to collapse.

Launch slideshow

More about asteroids:

• How about blasting 'em with lasers?
• How to 'hear' the Russian meteor
• Asteroids vs. comets: Threats compared
• NBCNews.com archive on asteroids

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Tue Feb 26, 2013 6:23 PM EST

SpaceX said it completed a successful test of the engines on its Falcon 9 rocket on Monday, in preparation for Friday's planned cargo launch to the International Space Station.

The California-based rocket company's unmanned Dragon capsule is due to deliver about 1,200 pounds (550 kilograms) of supplies to the space station and bring back 2,300 pounds (1,050 kilograms) of cargo, including scientific samples and space station hardware.

Monday's static-fire test was aimed at checking the performance of the Falcon 9 first stage's nine engines before they're called upon to loft the second stage and the Dragon capsule toward orbit on Friday. The rocket was held down onto its launch pad at Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida for the engine firing, which came at the end of a dress rehearsal for Friday's countdown.

"SpaceX engineers ran through all countdown processes as though it were launch day," the company said in a statement issued after the 1:30 p.m. ET firing. "All nine engines fired at full power for two seconds, while the Falcon 9 was held down to the pad. SpaceX will now conduct a thorough review of all data and continue preparations for Friday's targeted launch."

In a Twitter update, SpaceX's billionaire founder, Elon Musk, reported that the static-fire test looked good: "Engines generated 433 tons of thrust, parameters nominal."

SpaceX said the first opportunity for launch will come at 10:10 a.m. ET on Friday. This is the third Dragon to be sent to the space station, and the second flight under the terms of a $1.6 billion, 12-flight cargo resupply contract with NASA.

Another company, Virginia-based Orbital Sciences Corp., has a separate $1.9 billion contract to deliver supplies to the space station but has not yet begun flying its Antares rocket and Cygnus cargo capsule. On Friday, Orbital completed a successful static-fire test of Antares' engines in preparation for the rocket's first flight, which is expected to take place later this year.

NASA's contracts with SpaceX and Orbital are meant to help fill the gap left by the retirement of the space shuttle fleet in 2011. Russian, European and Japanese unmanned spacecraft are also used to send supplies to the space station, but Russia's Soyuz capsule is the only spacecraft currently cleared to transport astronauts to and from orbit. NASA is providing more than $1 billion to SpaceX, the Boeing Co. and Sierra Nevada Corp. to support the development of new crew-capable spacecraft for low Earth orbit.

More about SpaceX's mission:

• Dragon space station launch set for March 1
• These space capsules can fit on your desk
• SpaceX's press kit for the March 1 mission

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Vulcan and Cerberus (or Kerberos) emerged as the people's choices for naming Pluto's tiniest moons in the SETI Institute's "Pluto Rocks" contest, which ended on Monday. But in the course of running the contest, the organizers fielded 30,000 write-in suggestions — and you may well see some of those suggestions surface in the future.

"I've been delighted by the response," said Mark Showalter, a planetary scientist at the SETI Institute who played a leading role in the discovery of Pluto's fourth and fifth moons. Showalter was the point person for the moon-naming contest, which drew more than 450,000 online votes over the past two weeks.

More than 20 names were on the ballot, including Vulcan (the Roman god of fire) and Cerberus (the watchdog of the underworld). Vulcan was added to the list after the contest started, at the urging of "Star Trek" actor William Shatner, and grabbed the lion's share of the votes. But there were scads of other suggestions that weren't used, mostly because they weren't in line with the International Astronomical Union's tradition that the moons of Pluto should be named after figures from Greek or Roman mythology with some sort of connection to the underworld. Pluto was himself the mythological god of the underworld.

It's the IAU that has the final say over the names for the moons, which were discovered over the past couple of years and are now known merely as P4 and P5. Now that the crowdsourcing contest is over, Showalter willl be meeting with his colleagues on the discovery team and discussing whether to go with Vulcan and Cerberus or some other names. The names selected by the discoverers will then be considered by IAU committee members for adoption or reconsideration.

"It could take one to two months for the final names of P4 and P5 to be selected and approved," Showalter said on the "Pluto Rocks" website. "Stay tuned."

M. Buie / SwRI / NASA / ESA

These two pictures of Pluto represent the Hubble Space Telescope's most detailed view of the dwarf planet, but pictures from NASA's New Horizons probe should provide better resolution.

During a Google+ Hangout, Showalter mentioned the two most frequently suggested names that were left off the ballot. No surprise there: Considering that Pluto is a Disney cartoon character as well as a dwarf planet, you'd expect that Mickey and Minnie (as in Walt Disney's talking mice) would be the favorites.

"Yes, I am a big fan of Disney myself, but no, they are not compliant names," Showalter said. Although Mickey and Minnie make a cuter couple than Orpheus and Eurydice, they're not Greek or Roman mythological characters connected with the underworld.

Some of the other names, however, may come up again. When NASA's New Horizons probe sails past Pluto in 2015, still more mini-moons might be spotted. P6, P7 and so on would provide additional opportunities for the "compliant names" on Showalter's newly expanded list. And that's not all: New Horizons' camera could to snap pictures of previously unseen features on Pluto and its moons, That opens up a new frontier for names.

The names of planetary features don't have to follow the rules about Greek or Roman mythology: On Mercury, for example, craters are named after famous writers and artists. The hydrocarbon lakes detected on Titan, Saturn's largest moon, are named after the earthly lakes they resemble. Titan's mountains are named after the fictional mountains from "The Lord of the Rings" and other works by J.R.R. Tolkien, while the Saturnian moon's dark plains are named after planets from the "Dune" science-fiction series.

For Pluto and its moons, "we have all kinds of options," Showalter said. He noted that the naming suggestions followed some potentially appealing trends — specifically, Norse mythological figures as well as characters and locations from the "Star Wars" movie series and H.P. Lovecraft's fantasy and horror tales. Might we hear about Mount Loki, the Hoth ice sheet or Cthulhu Crater in the years to come? Will some scientist pick up on the Vulcan connection and start naming the hills of a Plutonian moon after Worf, Quark, Chakotay and T'Pol? To paraphrase another character from the "Star Trek" saga: "Make it so!"

More about planetary names:

• Uwingo aims to create Baby Planet Name Book
• How about better names for alien planets?
• Solar system's not changing — just the lingo

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Nine distant relatives of King Richard III are demanding that the British government reverse its decision to have his skeleton reburied at Leicester Cathedral, near the parking lot where it was found, and give it a resting place in York instead.

The open letter, published late Sunday by British newspapers such as The Telegraph and the Daily Mail, is just one of several efforts seeking a burial at York Minster for the more than 500-year-old remains, which were discovered last year by researchers from the University of Leicester. This month, the researchers said DNA analysis and other forensic tests proved "beyond reasonable doubt" that the skeleton was that of Richard III.

The English monarch reigned for just two years before he was killed in battle in 1485, but he was immortalized in William Shakespeare's play, "Richard III," in which he was portrayed as a hunchbacked villain. Richard III's legions of modern-day fans say he wasn't really all that bad — and the row over what to do with his bones has added a new twist to the drama.

"We, the undernamed, do hereby most respectfully demand that the remains of King Richard III, the last Plantagenet King of England and our mutual ancestor, be returned to the city of York for formal, ceremonial reburial," the statement from his relatives says. "We believe that such an interment was the desire of King Richard in life and we have written this statement so that his wishes may be fully recognised and upheld. King Richard III was the last King of the House of York and the last of the Plantagenet dynasty which had ruled England since the succession of King Henry II in 1154.

"We, the undernamed blood descendants, unreservedly believe that King Richard is deserving of great recognition and respect and hereby agree to dutifully uphold his memory.

"With due humility and affection, we are and will remain His Majesty’s representatives and voice."

The statement was signed by nine individuals who have traced their ancestry back to Richard III's siblings. The nine signers are Charles E. Brunner, Stephen Guy Nicolay, Vanessa Maria Roe, Jacob Daniel Tyler, Paul Tyler, Raymond Torrence Bertram Roe, Linda Jane Roe, Eleanor Bianca Lupton and Charlotte Jane Lupton. Richard died childless and thus has no direct-line descendants.

Even before the remains were found, the British Ministry of Justice granted a license putting the University of Leicester in charge of the parking-lot dig and the disposition of any remains found there."The University of Leicester specified in its application that reinterment would occur in Leicester Cathedral if the remains were proved to be those of King Richard III," the institution said in a statement.

The university is currently working with the cathedral and Leicester's city council on plans for his reburial by August 2014. In the meantime, researchers are continuing to study the remains.

The long lead time means that the tug of war between Leicester and York, two cities that are 100 miles (160 kilometers) from each other, could continue for months. There are even those who want to see the remains interred in London's Westminster Abbey. But the nine relatives behind this week's open letter have no more standing than the other descendants of Richard III's family, who doubtless number in the thousands by now.

In that light, Leicester seems to have the strongest case, by virtue of legal grounds as well as the less rigorous "finders, keepers" rule and the dictum that possession is nine-tenths of the law. Do you disagree? Feel free to weigh in with your comments below.

More about Richard III:

• Study suggests Richard III spoke with a lilt
• King Richard III's face revealed after 500 years
• Richard III's 'discovery' was reported in 1935, too

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

M. Showalter / NASA / ESA

An image from the Hubble Space Telescope shows Pluto and its largest moon, Charon, surrounded by four smaller moons. P4 and P5 will be getting new names. One of them might be called Vulcan.

The organizer of a contest to name Pluto's two tiniest moons can't guarantee that either one of them will be called "Vulcan" — but now that the name nominated by the original captain on the "Star Trek" TV show has won first place in the voting, planetary scientist Mark Showalter promises to argue the best case he can.

"My starting position is that we should work with the names that received the most votes," Showalter told NBC News on Friday.

The "Pluto Rocks" voting concluded at noon ET Monday, and is being followed by a 1:30 p.m. Google+ Hangout sponsored by the SETI Institute, the place where Showalter works. Vulcan came out on top with 174,062 of the 450,324 votes cast. But don't expect Showalter to declare immediately that Vulcan is the choice for one of Pluto's moons.

"There will not be an announcement on Monday," he said.

For one thing, it's not totally up to Showalter to make the nomination. He's just one of the leading scientists on the discovery teams for P4 and P5, the two moons that were found in 2011 and 2012. All the members from each of the teams will have to agree on the names to be submitted to the International Astronomical Union for approval. Even then, the IAU could voice concerns about the names they submit, leading to alternate suggestions. Showalter said he's actually seen that happen in the case of the Uranian moon that ended up being called Cupid.

Kirk ... takes ... command
Vulcan wasn't on Showalter's initial list of prospects, but he added it to the ballot at the urging of William Shatner, the actor who played Captain James T. Kirk on the original "Star Trek" series in the late 1960s. Shatner favored the name because it was the fictional home planet of Kirk's pointy-eared science officer, Mr. Spock. "Let's hope the IAU thinks Vulcan is a good name," Shatner wrote in a tweet to his 1.35 million Twitter followers.

Showalter said Shatner's endorsement definitely skewed the results. "Early on, it's pretty clear there were some Trek fans who seem to have resorted to augmented voting technologies," Showalter said. But he's convinced that the groundswell of support for Vulcan is genuine, and he said he's "come up with a pretty good case" for using the name.

"I want people to feel that their vote counted," Showalter said.

The IAU's guidelines for Pluto's moons stipulate that they should be named after Greek or Roman gods who have some connection to the mythological underworld. Those guidelines worked for Pluto's three other moons, Charon (ferryman of the dead), Nix (goddess of darkness) and Hydra (a many-headed monster).

Vulcan has a family relationship to the underworld, in that he was Pluto's nephew. And in his capacity as the god of fire, Vulcan tended to hang out in the depths beneath Mount Etna and other volcanoes, rather than on the heights of Mount Olympus. That may not be Hell, exactly, but it's certainly the underworld.

Showalter admitted that it might be tricky to have the god of fire associated with one of the coldest places in the solar system. "It may well be there's a consensus that it's a great name, but not a great name for a moon of Pluto," he said. Also, the name Vulcan has been associated with a hypothetical planet that was thought to circle the sun within Mercury's orbit. The 19th-century French astronomer who discovered Neptune, Urbain Jean Joseph Le Verrier, spent fruitless years looking for it. Pluto's moon is in an entirely different place, but Showalter sees that as a potential plus.

"Maybe we'd be doing Le Verrier a favor by saying that when he was looking for the ninth planet inside Mercury's orbit, he was looking in the wrong direction," Showalter joked.

Some have said the name Vulcan should be reserved for a planet beyond our own solar system. In response, Showalter points out that there's no IAU procedure for giving names to extrasolar planets (beyond generic designations such as Kepler-37b or Gliese 163c). That situation may change if planet-naming ventures such as Uwingu take hold. But in the meantime, Showalter feels that Vulcan should at least be given a fair shot at solar system fame.

Another moon to name
So it's a sure thing that Showalter will try making the case for Vulcan. But what about the other Plutonian moon?

Cerberus held onto the No. 2 spot in the voting, with 99,432 votes, and so Showalter will argue the case for Cerberus as well. That name fits perfectly with the mythological underworld theme, because Cerberus was the three-headed hound that guarded the gates of the underworld.

One drawback is that there's already an asteroid named Cerberus, and the IAU doesn't want newly named celestial bodies to be confused with previously named objects. Showalter said there are at least two ways around that issue: One is to argue that the asteroid and the moon wouldn't be confused. The precedent for this is Io, a mythological name that refers to a Jovian moon as well as an asteroid. Another way out is to change the spelling slightly — say, to the Greek name Kerberos. One precedent for this is the Plutonian moon Nix, which uses an alternate spelling to avoid confusion with the asteroid Nyx. (By the way, there's already an asteroid named Vulcano, but that name is considered different enough from Vulcan,)

Opening the moon-naming process up to a vote has been a lot of work, even if it's a non-binding vote, and Showalter said he doubts that he'll do it again. But he's gratified by the response: The contest attracted hundreds of thousands of votes from scores of countries around the world, generated more than 30,000 write-in suggestions for names, and gave Pluto fans and "Star Trek" fans lots to think about.

What would Spock think about all this? Leonard Nimoy, the actor who played the alien on the original "Star Trek" show, said via Twitter that "'Vulcan' is the logical choice." I can imagine Spock saying that, but I can also imagine him uttering just one word. ...

More about Pluto and its moons:

• Pluto's moons offer clues to alien worlds
• Pluto's atmosphere larger than previously thought
• All about Pluto from NBCNews.com
• Cosmic Log archive on Pluto

This report was originally published Friday and was updated with the results of the "Pluto Rocks" contest on Monday.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Fri Feb 22, 2013 7:35 PM EST

NASA followed one of the classic rules for Internet videos during its first space-to-Earth Google Hangout on Friday: If you want to bring in the viewers, don't forget the cats.

Astronaut Tom Marshburn's demonstration of how an astronaut in the International Space Station's zero-gravity environment can imitate a falling kitty was one of the highlights of the hourlong video chat, which addressed more than 30 questions sent in via YouTube, Twitter, Facebook, Google+ and real-time hookups with kids across the country.

One of the questions, phrased in the form of a video, came from the host of the "Smarter Every Day" webcast series, a rocket engineer known as Destin. (He keeps mum about his last name to protect his kids, who appear in the webcasts.) Destin ran his own mini-video showing how a falling cat rights itself in the air to land on its feet, and asked if the astronauts could match that feat in zero-G.

"We don't have any cats onboard," said space station commander Kevin Ford, "but we have a medical doctor who maybe can try to demonstrate the next best thing to a cat."

Marshburn, who's a physician as well as an astronaut, then proceeded to float in front of the camera and twist his body to change position — not quite as adroitly as the cats, but not bad for a human.

"I hope you believe that what you saw happened with the cat isn't a mystery, and that it can happen in space, too," Ford concluded. You can watch the demonstration around the 33-minute mark in the Hangout video.

Other astronauts participating in the chat included Canada's Chris Hadfield aboard the station, and NASA's Ron Garan and Nicole Stott on the ground. They took questions passed along from social media by NASA moderator John Yembrick; from live-video hookups with classrooms at University High School in Orlando, Fla., and Mescalero Apache School in New Mexico; and from a youngster named Fred whose video link was facilitated by the Make-a-Wish Foundation.

Google

Astronauts Tom Marshburn, Kevin Ford and Chris Hadfield join the Google+ Hangout.

Here are a few more nuggets from the video:

• Hadfield said that this week's communications outage on the space station was "not that big a deal," and that the crew members were well-trained to operate the station even when they were out of contact with ground controllers. "It wasn't any sort of panic or anything, it was just us dealing with a problem on the ground, and our crew dealing with the problem on board," he said. 
• Getting into the right sleep cycle is a big challenge on the space station, where there are 16 sunsets and sunrises every day. Garan said that when it gets close to bedtime, some astronauts avoid looking out the window at Earth's bright side. Stott said NASA is experimenting with a scheme that makes the lighting inside the space station more bluish for the "morning" of the astronauts' workday, and more orangish during the "evening."
• The station's crew members showed off the medical kits they kept on board for health problems, but if there's a life-threatening emergency on board, astronauts would get into one of the Russian Soyuz capsules attached to the station and fly the stricken crew member back to Earth. "Our Soyuz is our ambulance," Marshburn said. 
• When the astronauts were asked which scientist from the past they wish they could bring to the space station, Marshburn instantly said Isaac Newton, who drew up physics' three laws of motion in the 17th century. "We see what he could only imagine," Marshburn said. 
• Taking pictures from space is a challenging task that requires advance training, due to the sharp contrast between the blackness of outer space and the brilliance of the planet below, Hadfield said. But there's one big plus: Because of the zero-G environment, it's a lot easier to handle huge telephoto lenses. "Every photographer in the world would love to have that much glass in front of their eyes ... and not have to balance it," Hadfield said.
• When the astronauts were asked about their growing social-media stardom, Hadfield said, "I don't think anybody tries to push the edge of human experience more than we do." Being able to see the whole world below is "too good an experience not to share," and avenues such as Twitter, Facebook and Google+ help facilitate that, he said. He noted that a lot of the astronauts' popularity had to do with their unique perspective. "We know just how lucky we are to be here," Hadfield said.

For more outer-space video goodness, tune in the Weekly Space Hangout at 3 p.m. ET Friday. Yours truly will be on the screen along with other scribes to review the week's space news, including the meteor blast that hit Russia a week ago.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

NASA

NASA astronaut Tom Marshburn (left), Canadian astronaut Chris Hadfield (center) and space station commander Kevin Ford strike a zero-G pose in the International Space Station's Harmony node. All three will participate in Friday's Google+ Hangout.

Friday's live Google+ Hangout represents one small step for NASA, one giant leap for the Web-based videoconferencing tool.

Space-to-Earth hookups are nothing new for the International Space Station: NASA TV regularly broadcasts video from the orbital outpost as it circles the globe at an altitude of 240 miles (385 kilometers). Astronauts have been sending Twitter updates and Flickr photos from space for years. Heck, even NASA's robots have Facebook pages. But Friday's hourlong event, scheduled to run from 10:30 to 11:30 a.m. ET, marks the first time that NASA has done a Hangout.

"We're looking forward to it," said Jason Townsend, a spokesman at NASA Headquarters in Washington.

He said NASA has selected 20 video questions from the scads that were sent in by the agency's social-media followers, and at least some of those questions will be aired for the space station astronauts to answer during a 20-minute downlink opportunity starting at 11 a.m. ET. "We're angling to fill every minute," Townsend told NBC News.

Three of the space station's six astronauts — station commander Kevin Ford, NASA colleague Tom Marshburn and Canada's Chris Hadfield — will participate in the space-plus-Earth Hangout. (The three others, all Russians, will presumably be minding the store.)

Townsend said that for the balance of the hour, questions will be handled by two NASA astronauts on the ground: Ron Garan, a social-media star who's in nearly 3 million Google+ circles; and Nicole Stott, who participated in the space station's first live NASA Tweetup in 2009.

Questions can be submitted during the Hangout via Google+, via Twitter (by including the hashtag #askAstro) and via NASA's Facebook page.

The outer-space Hangout is just the latest leap for NASA's social-media strategy: The Tweetups of the late space shuttle era have given way to a string of NASA Social gatherings. One took place just this week at NASA Headquarters. NASA regularly sets aside seats for social-media mavens at big events, including next month's SpaceX Dragon launch.

Last year, NASA's social-media teams presented 16 events that brought more than 1,000 followers to NASA facilities and other spacey locales. Mars Curiosity rover has been the star of the show, thanks in part to her (yes, her) 1.3 million Twitter followers. During the rover's landing last August, NASA served up a record 36 million webcast streams, and the six-wheeled robot has been known to check in to Foursquare from Mars.

How can the Three Amigos on the space station possibly compete with Curiosity (and her cantankerous, non-NASA-sponsored alter ego, Sarcastic Rover)? Tune in on Friday and find out.

More marvels from the space station:

• Astronaut's artistry hits warp speed
• Space-plus-Earth duet makes debut
• Online contest to boost space station power

After NASA's Hangout, keep an eye out for the Weekly Space Hangout, which brings space scribes together for an hour starting at 3 p.m. ET. Universe Today's Fraser Cain and Astrosphere's Scott Lewis (the Bald Astronomer) are among the ringleaders.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Mikhail Metzel / AP file

Millionaire spaceflier Dennis Tito flashes a thumbs-up sign during final preparations for his 2001 flight to the International Space Station. Now Tito is reportedly contemplating a mission to Mars.

By Alan Boyle,
Science Editor, NBC News

Dennis Tito, the millionaire investment whiz who became the first paying passenger to visit the International Space Station in 2001, has worked out a plan to send two astronauts to Mars and back without stopping. However, the privately backed 501-day flight would have to be launched in 2018 — or wait until the 2030s.

Details about the Red Planet flyby are trickling out in advance of a Washington news conference next week.

First word of the venture came out in a media advisory passed along by the SpaceRef website on Wednesday. The advisory from the Texas-based Griffin Communications Group describes a "Mission for America" that would capitalize on a favorable orbital opportunity to launch a round-trip mission to Mars in January 2018.

The advisory includes an invitation to attend a news conference at 1 p.m. ET Feb. 27 at the National Press Club in Washington, issued by the Inspiration Mars Foundation, which is described as a "newly founded nonprofit organization led by American space traveler and entrepreneur Dennis Tito."

Tito, a former rocket engineer, made his fortune as the founder of Wilshire Associates, a multibillion-dollar investment firm based in California. He made history in 2001 when he paid a reported $20 million for a ride aboard a Russian Soyuz spacecraft to the space station. At the time, the eight-day round trip was highly controversial and required changes in the policies governing space station operations. Since then, six other high-net-worth individuals have taken similar flights with little or no controversy. The current published price for such flights is upwards of $40 million.

In the nearly 12 years since his flight, Tito has taken a relatively low public profile in the private-sector spaceflight industry. Meanwhile, other millionaires and billionaires, ranging from SpaceX's Elon Musk to Amazon.com founder Jeff Bezos to Microsoft co-founder Paul Allen, have been in the vanguard. 

Little is known about the Inspiration Mars Foundation, and the name doesn't turn up in databases for tax-exempt nonprofit organizations. The Internet domain names "InspirationMars.com" and "InspirationMars.org" were registered anonymously last October. But other than that, the only information that could be gleaned about Inspiration Mars comes from the media advisory, which says it's "committed to accelerating America's human exploration of space as a critical catalyst for future growth, national prosperity, new knowledge and global leadership."

"This 'Mission for America' will generate new knowledge, experience and momentum for the next great era of space exploration," the advisory said. "It is intended to encourage all Americans to believe again, in doing the hard things that make our nation great, while inspiring youth through Science, Technology, Engineering and Mathematics (STEM) education and motivation."

In addition to Tito, the speakers listed for next week's news briefing include Taber McCallum and Jane Poynter, who are veterans of the Biosphere 2 life-containment experiment and the top executives at Paragon Space Development Corp., which develops life-support systems for spacecraft. Jonathan Clark, a former NASA flight surgeon who now serves as an adviser for several space ventures, is also due to appear. Veteran TV journalist Miles O'Brien, who was once in line to take a trip to the space station, is to serve as moderator.

Update for 10:58 a.m. ET Feb. 21: The media advisory doesn't describe the specifics of the proposed mission, but spaceflight consultant Jeff Foust, publisher of the online NewSpace Journal, has come across information that sheds lots of additional light on Tito's plans. It turns out that Tito is due to give a presentation at the IEEE Aerospace Conference in Montana next month. He and his co-authors discuss the project in a paper prepared for the presentation. Here's a quick rundown of what Foust found: 

The mission would involve a flyby of Mars with a free return back to Earth, without stopping. That type of low-energy trajectory requires a special set of orbital circumstances: The presentation says those circumstances exist for the 2018 opportunity but won't repeat until 2031.  Two astronauts living in spartan conditions could make the 501-day trip in a modified SpaceX Dragon capsule, launched by SpaceX's yet-to-be-flown Falcon Heavy rocket.

Be sure to read Foust's full item on NewSpace Journal.

The plan seems to be just on the edge of doability. Among the questions that come up: Would the Dragon have adequate radiation shielding for the long-duration, deep-space trip? Can the crew cope with long-term isolation in close quarters, as well as the health effects of an extended zero-G trip? Can the Falcon Heavy truly be ready for a Mars trip in time for the 2018 opportunity? And who's going to pay for all this? Although there's no price tag attached to the plan, doing the mission seems likely to require billions of dollars. Tito may be rich, but is he that rich?

Update for 1:05 p.m. ET Feb. 21: Griffin Communications has confirmed the substance of the media advisory but released no additional information. The logistics for next week's briefing at the National Press Club are still being worked out. It's not yet known whether the proceedings will be webcast.

Update for 6:18 p.m. ET Feb. 21: A few more tidbits have trickled out: Even though the IEEE paper focuses on the SpaceX Dragon and Falcon Heavy, that doesn't mean SpaceX's participation in the project is a sure thing. The astronauts could ride on any of a range of space vehicles. One thing is for sure, however: Tito, who is now 72 years old, will not be making the spaceflight himself.

Although the IEEE paper casts the "Mission for America" as a private-sector effort, NASA would play a supporting role in technology development. A source who has been told about Tito's plans said the 2018 effort was not meant to provide competition for NASA's exploration effort, but instead provide support. NASA is working on a long-range program to send astronauts to a near-Earth asteroid in the mid-2020s, and to Mars and its moons in the mid-2030s.

The source was not authorized to speak publicly about Tito's plans, and thus spoke with NBC News on condition of anonymity. 

More about Mars ambitions:

• SpaceX founder wants to send hordes to Mars
• How a TV show could create a Mars colony
• Counting down to a mission to Mars

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Thu Feb 21, 2013 3:32 AM EST

NASA / JPL-Caltech / MSSS

This image from NASA's Curiosity rover shows the first tablespoon of powdered rock extracted by the rover's drill. The image was taken after the sample was transferred from the drill to the rover's scoop.

The scientists and engineers behind NASA's Curiosity rover say they're thrilled to see the first tablespoon of rock dust drilled from the interior of a rock on Mars — and they're intrigued by the fact that it's gray, not red.

"We're seeing a new coloration for Mars here, and it's exciting for us," Joel Hurowitz, sampling system scientist for the Curiosity mission at NASA's Jet Propulsion Laboratory, told reporters during a teleconference on Wednesday.

Things could get more exciting in the next few days, when Curiosity's sampling system drops dollops of the dust into the rover's onboard chemistry labs, known as CheMin (which stands for Chemistry and Mineralogy) and SAM (Sample Analysis at Mars). The main goal of the $2.5 billion mission is to find organic compounds on Mars, and scientists suspect that the gray interior of rocks could preserve those organics better than the red, highly oxidized surface.

"All things being equal, it's better to have a gray color than a red color," said Caltech's John Grotzinger, the mission's project scientist, "just simply because oxidation ... is something that we know destroys organic compounds."

The rover has spent several weeks at a rock formation known as John Klein in preparation for this first drilling operation, six months into what's expected to be a two-year primary mission. Some scientists and engineers have been working for years in anticipation of Wednesday's first sight of ground-up rock in Curiosity's sampling cup.

"For the sampling team, this is the equivalent of the landing team going crazy after the successful touchdown," said JPL's Scott McCloskey, drill systems engineer for the Curiosity mission.

The sample came from a 2.5-inch-deep hole that Curiosity drilled into the Martian bedrock on Feb. 8. One of McCloskey's colleagues at JPL, sample system chief engineer Louise Jandura, noted that this was the first time a rover has drilled samples out of a rock on another planet. Earlier missions have used grinders to scrape off the top layer of a Martian rock, but none has gone down as deeply as Curiosity did.

"In the five-decade history of the Space Age, this is indeed a rare event," she said.

Grotzinger said getting the samples represented the final milestone in the commissioning process for the rover. Last week marked the "passing of the keys to the rover" from the engineering team to the science team, he noted. "It's a real big turning point for us," Grotzinger said. 

NASA / JPL-Caltech / MSSS

At the center of this image from NASA's Curiosity rover is the hole in a rock called "John Klein" where the rover conducted its first sample drilling on Mars. The drilling took place on Feb. 8. Several preparatory activities with the drill preceded this operation, including a test that produced the shallower hole on the right two days earlier.

NASA / JPL-Caltech / MSSS

This image from October 2012 shows the location of a sieve screen on the Curiosity rover that is used to remove large particles from samples before delivery to science instruments. Scientists say problems that came to light on a test unit on Earth have led them to change their procedures for sifting Martian samples.

Going through glitches
It will take a few more days to start analyzing the ground-up rock: Some of the material in the cup is being used to clear out the plumbing in the rover's sample delivery system. Once scientists back on Earth see imagery confirming that everything is working as expected, they'll give the go-ahead for more of the material to be shaken through a sieve and then deposited into CheMin and SAM for analysis.

A software glitch delayed the sampling operation, McCloskey said, but the team found a work-around that allowed the task to continue with no loss of functionality. "It didn't end up being a significant roadblock to getting this done," he said.

Another concern arose when engineers found that the sieve on one of the test items back on Earth started coming loose after about 60 shaking operations, also known as "thwacks." That was a signal to the rover team that there was "reason to be cautious," said JPL's Daniel Limonadi, lead systems engineer for Curiosity's surface sampling and science system.

The team decided to reduce the shaking time from 60 minutes to 20 minutes at a time, which should be long enough for most samples. If it isn't, the rover will just keep shaking the stuff until the job is done, Limonadi said.

What the rocks may reveal
Hurowitz said the evidence so far suggests that Curiosity is looking at a sedimentary rock formation that was "more likely deposited in water." Veins of whitish material appear to consist of calcium sulfate, which could provide additional clues to the formation's aqueous origins. He said about 25 separate analyses have been conducted with Curiosity's Alpha Particle X-ray Spectrometer, more than 100 images have been recorded by the Mars Hand Lens Imager, and the ChemCam instrument has taken 12,000 laser shots at the rock.

The gray color of the rock dust suggests that the interior of Martian rocks may reflect ancient geological processes that are significantly different from the current weathering process on the Red Planet, Hurowitz told NBC News.

"This is something that the science team is really excited about — the fact that the tailings from our drill operation aren't the typical rusty orange red that we associate with just about everything on Mars," he said. "You can probably bet that when things turn orange, it's because there's a rusting process of some kind going on that oxidizes the iron in the rock. So the fact that these rocks aren't that color may be telling us that these rocks didn't go through that process that usually turns things to rust on Mars. It may preserve some indication of what iron was doing in these samples without the effect of some later oxidative process."

Eventually, Curiosity will be commanded to retrace its route and head for a 3-mile-high (5-kilometer-high) mountain known as Aeolis Mons or Mount Sharp. But Grotzinger emphasized that the mission was "discovery-driven" — and that the rover team was in no hurry to have the rover make its mountain trek.

"We're going to take it one step at a time," Grotzinger said.

More about Mars:

• Curiosity finds organics, but are they from Mars?
• Mars rover driving through dried-up stream bed
• Cosmic Log archive on the Curiosity mission

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Ignacio Diaz Bobillo / Pampaskies.com

Comet PanSTARRS glows with a fanlike tail in this picture from Argentine astrophotographer Ignacio Diaz Bobillo.

The first of two comets expected to make a splash this year is already putting on a good show for Southern Hemisphere skywatchers — and by the time it makes its appearance in northern skies, Comet PanSTARRS should be visible to the naked eye.

C/2011 L4 PanSTARRS, which was discovered in 2011 by the Pan-STARRS telescope in Hawaii, isn't expected to be as much of a spectacle as Comet ISON, which could get as bright as the full moon in November. But it's on track to reach a brightness of at least magnitude 2 in early March. That's roughly equivalent to the brightness of Polaris, the North Star.

"This comet definitely is a dynamically new comet, so we do have the wild-card factor in there," Karl Battams of the Naval Research Laboratory told NBC News in an email. "In an ordinary year, this comet would be grabbing the headlines, but most people are so worked up over ISON that this one is getting short-changed a little. It should be a good one though. ... For us urban dwellers, we might need to dust off the binoculars to get a decent look."

Battams and other astronomers say PanSTARRS is a special case because it's apparently coming in from the Oort Cloud on the solar system's edge to make its first swing through the inner solar system. That's what makes PanSTARRS a wild card: There's a chance that the comet will get brighter than expected, or stay dimmer than expected, when it wheels around the sun. "Comets do love to surprise us," Battams said.

Right now, the comet is on display only in the Southern Hemisphere, but bright enough to be seen with the naked eye under optimal conditions (as bright as magnitude 4.2). Pictures taken through telescopes, such as the shots you see here from Pampaskies.com's Ignacio Diaz Bobillo in Argentina and amateur astronomer Terry Lovejoy in Australia, are already showing a fanlike double tail. One of the tails is a stream of dust illuminated by the sun, while the other is a glowing stream of ionized gas.

Terry Lovejoy via IfA/Hawaii

An image captured by Australian amateur astronomer Terry Lovejoy shows Comet PanSTARRS.

PanSTARRS should start showing up in the Northern Hemisphere around March 7. "To see it, you will need an unobstructed, cloudless view of the western horizon," the University of Hawaii's Institute for Astronomy said. "It is best to pick a dark spot, away from streetlights. Look in the direction of the sunset just after the sun has gone down. The comet will be just above the horizon."

It'll be tricky to spot the comet because of the glare of the twilight sky, and even trickier after March 12, when the light of the moon will start interfering. You'll definitely need binoculars to see the tails. Actually, March 12 or 13 might be the best time for your comet-viewing, picture-taking party, because PanSTARRS should be visible alongside a pretty crescent moon in western skies.

"By the end of March, the comet will no longer be visible in the evening sky, but if you get up early, you may be able to see it in the eastern sky just before sunrise," the institute said. "However, by then the comet will be farther from both the sun and Earth, and will therefore be fainter."

When PanSTARRS fades, keep your binoculars in a handy place. You'll want to bring them out again for this year's other sky highlights, including the advent of Comet ISON in November.

Update for 10:35 p.m. ET Feb. 25: Here's a video featuring the two classiest comets in the night sky, Comet Lemmon and Comet PanSTARRS, as captured by Australia's Alex Cherney:

More about the year of the comets:

• Time for bright comets to grace the skies
• NASA probe tracks 'Comet of the Century'
• Comet spectaculars and other sky highlights for 2013
• Flash interactive: Inside a comet

Hat tip to Daniel Fischer.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Wed Feb 20, 2013 2:44 PM EST

Chad Blakley / Lights Over Lapland

The northern lights vie with a waxing moon over Sweden's Abisko National Park on Monday night.

One look at SpaceWeather.com's aurora gallery will tell you that February has been a very good month for auroral displays in northern latitudes, and an upswing in solar activity promises more to come.

One of the hot spots is Sweden's Abisko National Park, which is the favorite hangout for Chad Blakley of Lights Over Lapland. "We have seen powerful auroras in the sky above Abisko for 13 nights in a row, and it looks like there are more to come!" he wrote in an email Tuesday. "Last night I witnessed one of the finest aurora displays I have seen in many months. February 2013 is turning out to be one of the best months for aurora watching I have ever seen!"

You can get a sense of how Blakley's nights have been going by taking a minute to watch Blakley's time-lapse video below. But don't stop there: I'm also including a time-lapse from Helge Mortensen, a photographer based in Tromso, Norway, and from Oli Haukur and the OZZO Photography team in Iceland.

Scandinavia, Alaska and northern Canada are all hot spots for the northern lights this time of year, even though it gets chilly at night. The auroral displays might dip farther south if we get a nice geomagnetic storm coming our way, and the solar weather outlook suggests that could happen. A new sunspot region known as AR 1678 has cropped up, and SpaceWeather.com says this region could give rise to "a significant solar flare."

Check out the usual places for space weather updates, including the National Oceanic and Atmospheric Administration's Space Weather Prediction Center as well as the center's Facebook page and its Ovation aurora forecast chart. You'll also want to keep tabs on the Canadian Space Agency's AuroraMAX website — and the Lights Over Lapland Facebook page, where you'll find an awesome image of the aurora glowing beside a moon halo.

More auroral glories:

• Northern lights boosted by 'The Blob'
• PhotoBlog's northern-lights archive
• Slideshow: Aurora's greatest hits

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

MSNBC TV

The classic rock-paper-scissors game encourages a strategy of second-guessing. In this particular showdown, "rock" (the closed fist) beats "scissors" (the forked fingers). "Paper" is represented by an open palm.

When people try to second-guess a rival, they don't eighth-guess or ninth-guess them: Using a glorified version of the classic rock-paper-scissors game, researchers have found that players tend to converge on a strategy of thinking around two steps ahead.

They say their findings could shed light on other pursuits where rivals have to engage in cycles of second-guessing — including fashion trends, political campaigns and the financial markets.

"Anticipation may be the motor that keeps fads running in cycles," Seth Frey, a doctoral candidate studying psychology and brain science at Indiana University, said in a news release. "It could be a source of the violent swings that we see in financial markets. Anyone in a bidding war on eBay may have been caught in this dynamic. If the bidders are tweaking their increasing bids based on the tweaks of others, then the whole group may converge in price and determine how those prices rise. The process isn't governed by the intrinsic value of that mint-condition Star Wars lunch box, but on the collective dynamics of people trying to reason through each other's thoughts."

Frey and Robert Goldstone, who directs the Percepts and Concepts Laboratory at Indiana University, designed a laboratory experiment designed to find out how strategies changed over repeated cycles. They decided against the relatively limited repertoire of rock-paper-scissors — the hand-flashing game in which scissors cuts paper, paper covers rock, and rock dulls scissors. Instead, they used a guessing game in which players guess a number between 1 and 24. A player wins a point when he or she guesses a number exactly one step higher than another competitor. There's one exception: 1 beats 24.

During 22 sessions at the university, 123 psychology students participated in the "Mod Game," in small groups. Each point that was won in the game earned a player 10 cents.

The results were published online by the journal PLOS ONE on Monday. Players could have simply guessed random numbers during each round, but that's not what happened. Over the course of repeated guessing games, the players tended to fall into the pattern of raising their guesses in a cluster that cycled through all the choices. The behavior suggested that players tried to guess what their rivals were guessing about their guess. In a video, Frey compared the pattern to a famous poisoning scene in the movie "The Princess Bride."

As the guessing games continued, the speed of the cycling accelerated. After 200 rounds, the rate of cycling gradually reached an average of 2.35 "thinking steps," Frey and Goldstone reported. They suggested that a synchronicity in the guessing was beneficial for the group as a whole, because the players earned no payoff if they thought too far ahead.

"At a core level, people's guesses do converge, and that's interesting because dominant models suggest otherwise," Goldstone said in the news release. "Even though people are trying to beat each other out, they end up in synchronicity."

More about the science of rock-paper-scissors:

• Rock-paper-scissors robot will beat you every time
• Science reveals how to win at rock-paper-scissors
• Judge orders rock-paper-scissors to decide dispute

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

A pixelated profile from NASA's Goldstone radar dish makes the passing asteroid 2012 DA14 look a bit like an out-of-control Viper space fighter from "Battlestar Galactica." But the real-life asteroid is almost five times as big, and might well pack a bigger wallop if it ever hit our planet.

NASA's Jet Propulsion Laboratory on Tuesday released a movie combining 73 radar images of 2012 DA14, captured over the course of eight hours on the night of Feb. 15-16. The image resolution is 13 feet (4 meters) per pixel.

In a news release, NASA said the images show the roughly 130-foot-long (40-meter-long) asteroid moving away from us, at a distance ranging from 74,000 miles to 195,000 miles (120,000 to 314,000 kilometers). These readings were made just hours after the time of closest approach, when the asteroid came within 17,200 miles (27,680 kilometers) of our planet.

2012 DA14's close encounter on Feb. 15 was eclipsed by the nuclear-scale impact of a meteor over the Russian city of Chelyabinsk earlier in the day — a widely witnessed event that caused more than 1,200 injuries and did an estimated $33 million in damage. NASA said the asteroid behind Russia's meteoric display was about a third the size of 2012 DA14.

If 2012 DA14 had hit instead, the damage would have been much, much worse. Experts have compared the bigger space rock to the object that blew up over a Siberian forest in 1908, knocking down millions of trees over an 820-square-mile area. As it is, the Russian meteor rates as the biggest observed cosmic impact since Siberia's Tunguska event.

JPL's radar observations, which continue through Wednesday, are aimed at fine-tuning the calculations of 2012 DA14's future orbit by getting a better fix on its size, shape, rotation, surface features and surface roughness. For what it's worth, the asteroid's estimated length of 40 meters along its long axis is between four and five times the length of the Colonial Viper spacecraft that buzzed the Cylons in the "Battlestar Galactica" TV series.

The asteroid's path was perturbed by Earth's gravitational field in such a way that it won't come as close in the foreseeable future. However, a better understanding of its orbit and its composition could help scientists prepare for encounters with other asteroids — and figure out the best way to divert potentially threatening near-Earth objects.

The radar observation campaign is led by JPL's Lance Benner and Marina Brozovic.

Here are a more views of 2012 DA14 from other observers:

An international team led by MIT's Nicholas Moskovitz observed asteroid 2012 DA14 with a number of telescopes, including the 2.1-meter telescope at Kitt Peak National Observatory. This animated image shows the asteroid as it was leaving Earth's vicinity. Check out the National Optical Astronomy Observatory's news release for more information. If you missed seeing the animation, click here for a refreshed view.

More about the asteroid:

• Watch a passing asteroid fade out
• How it rates among asteroid hits and misses
• Earth kicks asteroid into safer orbit
• NBCNews.com's asteroid archive

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Tue Feb 19, 2013 5:24 PM EST

NASA restored its communication link with the International Space Station on Tuesday, hours after it was knocked out by a glitch encountered during a computer software upgrade.

Josh Byerly, a spokesman for NASA's Johnson Space Center, told NBC News that the link was restored at 12:34 p.m. ET.

The outage began at about 9:45 a.m. ET, during a planned upgrade for the custom-coded software that NASA uses for command and control as well as voice and data communication with the space station, via the Tracking and Data Relay Satellite system, or TDRS. When the system switched from the primary computer to a backup computer, communications were lost immediately, Byerly said.

During the outage, the station's crew had to rely on Russian ground stations for communications. Those ground stations are in range only when the station is flying overhead, roughly every 90 minutes. "It's just like back in the old days, during Gemini," Byerly said. "We still need those antennas from time to time."

Byerly said NASA astronaut Kevin Ford, the station's commander, received instructions for resetting the computers during the Russian communication passes.

Similar software upgrade problems have occurred before, Byerly said, and engineers are looking into the specific causes for Tuesday's glitch. "It is a problem, but the crew was not in danger," he told NBC News.

More about space station operations:

• Yearlong space missions pose risks
• NASA says station is safe from hackers

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

MGH-UCLA Human Connectome Project

This visualization shows the grid structure of major pathways of the human brain, as mapped by the NIH Blueprint Human Connectome Project. Click on the image for a Flash interactive exploring the brain.

BOSTON — The brain-mapping project that the Obama administration wants to facilitate isn't necessarily aimed at adding billions of dollars to the money already being spent on research, according to the scientists who inspired the idea. Instead, it's aimed at harnessing new technologies to uncover the secrets of neural function less expensively and more completely.

"We can bring down the cost and increase the quality of the technology," said Harvard geneticist George Church, one of the researchers who proposed the Brain Activity Map Project last year. "We are trying to work with current funding [levels] to bring down the cost."

The New York Times reported on Monday that the White House has embraced the idea of having the Office of Science and Technology Policy spearhead the project, with participation by the National Institutes of Health and other federal agencies. The federal initiative is to be unveiled as early as next month, the Times quoted its sources as saying.

The roots of the project go back months if not years earlier: The goals of the BAM Project were outlined last June in a white paper appearing in the journal Neuron. The researchers proposed a 15-year international effort to map the functions of the brain's complex neural circuitry to an unprecedented degree — using traditional tools such as magnetic resonance imaging in combination with novel technologies such as nanosensors and wireless fiber-optic probes that can be implanted into the brain, and genetically engineered cells that can be linked up with brain cells to record their activity.

The scientists' idea was to start with mice and work their way up to primates. "We do not exclude the extension of the BAM Project to humans, and if this project is to be applicable to clinical research or practice, its special challenges are worth addressing early," they wrote.

The discoveries generated by the effort could point to new strategies for dealing with brain-centered maladies such as Alzheimer's disease, Parkinson's disease, autism and schizophrenia.

Church and his colleagues compared the BAM Project's potential impact to the effects of the $3.8 billion Human Genome Project, a 13-year-long effort that analysts say generated $796 billion in economic activity. "After the genome project, we brought the cost [of whole-genome sequencing] down by a million-fold," Church said. Advanced technologies for studying brain activity could bring savings on the same scale, he said.

In this month's State of the Union Address, President Barack Obama made a similar point: "Every dollar we invested to map the human genome returned $140 to our economy — every dollar.  Today, our scientists are mapping the human brain to unlock the answers to Alzheimer's.  They’re developing drugs to regenerate damaged organs; devising new material to make batteries 10 times more powerful.  Now is not the time to gut these job-creating investments in science and innovation.  Now is the time to reach a level of research and development not seen since the height of the Space Race."

Debate over the dollars
The Times' report on the project quoted scientists familiar with the BAM Project as saying they hoped it would receive as much support as the Human Genome Project did, which amounted to more than $300 million a year. That was widely interpreted as implying that more than $3 billion would be shifted over to the effort from other federally supported research over the next decade – a prospect that rankled some observers.

"If there is money for frivolities like the Billion Dollar Brain Project, doesn't it show that NIH has too much money?" evolutionary geneticist Detlef Weigel of the Max Planck Institute for Developmental Biology wrote in a Twitter comment.

Some scientists noted that the European Union has already established a Human Brain Project in cooperation with a range of research centers, including some that are expected to play a role in the BAM Project. The European-led project is due to receive up to 1 billion euros ($1.3 billion) over the next decade.

Michael Eisen, a biologist at the University of California at Berkeley, pointed to a blog posting in which he said grand projects in biology such as Project ENCODE for DNA analysis were emerging as the "greatest threat" to individual discovery-driven science because they crowded out less costly, smaller-scale studies.

"It's one thing to fund neuroscience, another to have a centralized 10-year project to 'solve the brain,'" Eisen wrote in a Twitter update.

Emphasis on existing funds
Church said he couldn't speak for the federal government, and he didn't rule out the possibility that the project would receive new funding. But he noted that the concept outlined last year emphasized better coordination of existing publicly and privately supported brain research efforts, which already receive hundreds of millions of dollars per year.

"We want to use existing funds," he told NBC News.

The BAM Project received a strong endorsement from Allan Jones, chief executive officer of the privately backed Allen Institute for Brain Science.

"Our own work over the last 10 years has shown that large-scale brain research and sharing vast data sets and tools publicly for use by scientists around the world accelerate progress and catalyze important research advances across the field," Jones said in a statement emailed to NBC News. "In early 2012, we launched our large-scale initiative to understand brain activity, creating a foundation for other related projects."

The Allen Institute helped organize a workshop that gave rise to last year's white paper proposing the BAM Project, and it is also a partner in the Human Brain Project. Jones said such efforts "complement our work at the Allen Institute for Brain Science and hold promise for helping to bring on new discoveries about the human brain and bring us ever closer to much needed advances in medicine."

More about the brain:

• How scientists are hacking into brain waves
• Paul Allen starts up 'brain observatory' with $300 million
• Flash interactive: Road map of the mind
• Cosmic Log archive on brain science

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Corbis

An artist's conception visualizes the big bang at the universe's beginning — or could it be the end?

BOSTON — If the "Higgs-like particle" discovered last year is really the long-sought Higgs boson, the bad news is that its mass suggests the universe will end in a fast-spreading bubble of doom. The good news? It'll probably be tens of billions of years before that particular doomsday arrives.

That's one of the weirder twists coming out of the continuing analysis of results from Europe's Large Hadron Collider, which produced the first solid evidence for the existence of the Higgs boson last year. Current theory holds that the Higgs boson plays a role in imparting mass to other fundamental particles. Confirming the discovery of the Higgs would fill in the last blank spot in that theory, known as the Standard Model.

Physicists discussed the state of the Higgs quest in Boston on Monday during the annual meeting of the American Association for the Advancement of Science.

So far, the particle that was found at the LHC fits all the requirements for the Higgs boson, but scientists aren't quite ready to confirm that the particle is really, truly the Higgs boson. It could be, say, just the first of multiple particles involved in the process. "The door is still very much open that there's [another] particle that has a role to play, or even more than that," said Christopher Hill, a physicist at Ohio State University who is also deputy physics coordinator for the LHC's Compact Muon Solenoid experiment.

The LHC has just started a two-year shutdown for equipment upgrades — and Howard Gordon, deputy chair of the physics program at Brookhaven National Laboratory, said "it's going to take another few years" after the collider is restarted to confirm definitively that the newfound particle is the Higgs boson.

In the meantime, physicists have tightened their estimates of the particle's mass: Hill said the current estimate from the Compact Muon Solenoid is 125.8 billion electron volts, or 125.8 GeV, plus or minus 0.6 GeV. The figure from the LHC's other Higgs-boson detector, known as ATLAS, is 125.2 GeV, plus or minus 0.7 GeV.

Those figures can be factored into equations that point to the long-term fate of the universe, said Joseph Lykken, a theoretical physicist at Fermilab.

So what's the outlook?

"If you use all the physics that we know now, and we do what we think is a straightforward calculation, it's bad news," Lykken said. "It may be that the universe we live in is inherently unstable. At some point, billions of years from now, it's all going to be wiped out."

He said the parameters for our universe, including the Higgs mass value as well as the mass of another subatomic particle known as the top quark, suggest that we're just at the edge of stability, in a "metastable" state. Physicists have been contemplating such a possibility for more than 30 years. Back in 1982, physicists Michael Turner and Frank Wilczek wrote in Nature that "without warning, a bubble of true vacuum could nucleate somewhere in the universe and move outwards at the speed of light, and before we realized what swept by us our protons would decay away."

Lykken put it slightly differently: "The universe wants to be in a different state, so eventually to realize that, a little bubble of what you might think of as an alternate universe will appear somewhere, and it will spread out and destroy us."

That alternate universe would be "much more boring," Lykken said. Which led him to ask a philosophical question: "Why do we live in a universe that's just on the edge of stability?" He wondered whether a universe has to be near the danger zone to produce galaxies, stars, planets ... and life.

Even Hill found it interesting that the parameters of particle physics put our universe right along the critical line. "That's something new, which we didn't know before, and which leads some of us to that there's something else coming," Hill said.

When Hill referred to "something else," he was talking about new discoveries in physics — not the end of the world. Lykken emphasized that it would be at least tens of billions of years before vacuum instability took hold.

"To get the exact number, we need more funding," he joked.

More about the fate of the universe:

• A bleak and lonely outlook for the universe
• Will time end in 3.7 billion years? Maybe, or maybe not
• Flash interactive: Beyond the big bang

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

BOSTON — Neuroscientists are following through on the promise of artificially enhanced bodies by creating the ability to "feel" flashes of light in invisible wavelengths, or building an entire virtual body that can be controlled via brain waves.

"Things that we used to think were hoaxes or science fiction are fast becoming reality," said Todd Coleman, a bioengineering professor at the University of California at San Diego. Coleman and other researchers surveyed the rapidly developing field of neuroprosthetics in Boston this weekend at the annual meeting of the American Association for the Advancement of Science.

One advance came to light just in the past week, when researchers reported that they successfully wired up rats to sense infrared light and move toward the signals to get a reward. "This was the first attempt … not to restore a function but to augment the range of sensory experience," said Duke University neurobiologist Miguel Nicolelis, the research team's leader.

The project, detailed in the journal Nature Communications, involved training rats to recognize a visible light source and poke at the source with its nose to get a sip of water. Then electrodes were implanted in a region of the rats' brains that is associated with whisker-touching. The electrodes were connected to an infrared sensor on the rats' heads, which stimulated the target neurons when the rat was facing the source of an infrared beam. Then the visible lights in the test cage were replaced by infrared lights.

It typically took about four weeks of practice for the rats to figure out how to use their new infrared sensory system, but eventually the rats could respond to the invisible light as well as they responded to the visible light. Presumably, they could "feel" where the infrared flash was coming from, as part of their whisker-touching sense.

Nicolelis said the experiment showed that the brain is "much more plastic than we thought" when it comes to adapting to new stimuli.

That plasticity is the key to another set of experiments he and his colleagues have been conducting with rhesus monkeys, in which the monkeys learn to use their brain waves to control robotic arms or manipulate virtual objects on a computer screen. Over the years, Nicolelis' research team has developed a brain-cap system for monkeys that can pick up neural signals in almost 2,000 channels simultaneously, and send them wirelessly to a computer for processing. Nicolelis indicated that he was closing in on the goal of creating a system that could control a full-body exoskeleton.

"We can get animals to control the whole body now, when you get to the 1,000-neuron margin," he said.

Such work feeds into the Walk Again Project, a multinational effort to develop next-generation, full-body prosthetics for people with disabilities. Nicolelis wants to have an experimental brain-controlled exoskeleton ready in time to make its debut at next year's World Cup soccer finals, which are to be hosted by Brazil, Nicolelis' native country.

"We hope we will open the World Cup with a paraplegic young adult walking onto the field," he said.

Coleman, meanwhile, is working on ways to make brain-control devices less obtrusive. He is among several researchers who have been developing stamp-sized wireless sensors that can be worn like temporary tattoos. Such sensors can be used to monitor a person's medical signs — but if they're worn on the head, it's possible to pick up brain waves. In fact, Coleman found that the wireless tattoo sensors worked as well as the conventional, wired stick-on electrodes.

The results suggest that someday, it might be possible to develop a computer program to read the brain-wave patterns sent in by a tattoo on your forehead, and then fine-tune a virtual character to respond as if it was reading your thoughts.

The tattoos could have more down-to-earth applications in the medical field: In the future, such sensors could be used to monitor a newborn's brain for any signs of abnormality, or an older person's brain for signs of cognitive impairment.

"As we age, our ability to respond, or to modulate our attention to different new types of inputs, will start to slow down," Coleman said in a video interview distributed by AAAS. "Imagine if we could ... mount a sticker to the forehead that can provide quantitative outputs — measurements of that."

Does all this sound like a dream come true for the disabled, or a nightmare for folks worried about mind-reading robots? Feel free to weigh in with your thoughts in the comment section below.

More about the brain:

• Machine that feels is key to 'Jedi' prosthetics
• How scientists hacked into Stephen Hawking's brain
• Flash interactive: Road map of the mind
• Cosmic Log archive on brain science

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Slideshow: Meteor streaks over Siberia

Yekaterina Pustynnikova / Chelyabinsk.ru via AP

Click through scenes from Russia's Chelyabinsk region, where a huge meteor fireball set off alarms, injured hundreds of people and caused a factory roof to collapse.

Launch slideshow

Scientists have raised their estimates of the size and power of what turns out to be the most widely witnessed asteroid strike in modern history. The size estimate puts the object that caused Friday's meteor blast over Russia in a troublesome category of asteroids: big enough to cause damage, but small enough to evade detection.

The new estimates, based on additional readings from a sensor network built to detect nuclear blasts, suggest the meteor released the energy equivalent of nearly 500 kilotons of TNT. That's about 30 times the power of the Hiroshima atomic bomb.

Experts have been assessing the level of the meteor explosion using a network of infrasound sensors that were set up under the terms of the Comprehensive Test Ban Treaty to check for changes in atmospheric pressure caused by nuclear blasts.

"These new estimates were generated using new data that had been collected by five additional infrasound stations located around the world — the first recording of the event being in Alaska, over 6,500 kilometers away from Chelyabinsk," NASA's Jet Propulsion Laboratory said in a statement.

NASA now says the Chelyabinsk object must have been about 55 feet wide (17 meters wide) with a mass of 10,000 tons before it entered Earth’s atmosphere.

"We would expect an event of this magnitude to occur once every 100 years on average," Paul Chodas of NASA's Near-Earth Object Program Office said in the statement. "When you have a fireball of this size, we would expect a large number of meteorites to reach the surface, and in this case there were probably some large ones."

Searchers have been focusing on a frozen lake about 50 miles (80 kilometers) west of Chelyabinsk, where they suspect meteorite fragments made a 20-foot-wide (6-meter-wide) hole in the ice. Searchers have found fragments up to a half-inch wide (1 centimeter wide) that might have come from the meteor, but nothing bigger yet, according to reports from Russia.

Experts emphasized once again that the meteor's trajectory was significantly different from the path of asteroid 2012 DA14, a 150-foot-wide (45-meter-wide) space rock that passed harmlessly within 17,200 miles (27,600 kilometers) of Earth later Friday. Thus, 2012 DA14 was "a completely unrelated object," NASA said.

The space agency said Friday's Russian meteor was the largest reported since 1908, when an asteroid roughly the size of 2012 DA14 exploded over a remote wooded area in Siberia's Tunguska region. That blast flattened millions of trees over a 820-square-mile area, but was not widely seen. Friday's event, in contrast, took place over a city of 1.1 million inhabitants, and hundreds of millions more watched the videos that were distributed over the Internet.

As powerful as the meteor blast was, it's on the low end of the asteroid impact scale. Astronomers estimate that there are about a million potentially hazardous near-Earth objects smaller than 100 meters (330 feet) in width, and only about 1 percent of those have been cataloged. For the time being, NASA is focusing on detecting and tracking near-Earth asteroids wider than 100 meters.

But what about the smaller ones?

"Defending the Earth against tiny asteroids such as the one that passed over Siberia and impacted there is a challenging issue. That is something that is not currently our goal," Chodas told reporters on Friday.

The asteroid behind Friday's meteor blast would have been particularly hard to spot during its final approach, because it was coming from Earth's daylit side. The asteroid would have been lost in the sun's glare and undetectable by ground-based telescopes, said Bill Cooke, the head of the Meteoroid Environment Center at NASA's Marshall Space Flight Center.

Several programs on the horizon hold the promise of finding the smaller asteroids that could threaten Earth:

• NASA has just started funding the Asteroid Terrestrial-impact Last Alert System, or ATLAS, which aims to establish two telescopes in Hawaii dedicated to scanning the skies for potential threats.
• The non-profit B612 Foundation has been raising money to launch its Sentinel Space Telescope as early as 2018. Sentinel would scan Earth's surroundings from an outward-looking position in a Venus-like orbit, interior to Earth's orbit. Such a project could provide advance warning for asteroids like the one that blew up on Friday. Former Apollo astronaut Rusty Schweickart, one of the foundation's founders, said he was "overwhelmed" by requests for information after Friday's blast. "It's pretty bonkers at the moment," he told NBC News.
• Planetary Resources, a commercial venture, is developing a fleet of Arkyd-100 space telescopes to identify near-Earth asteroids, in hopes of sending mining operations to them in the decades to come. "As the company ultimately develops the capability and infrastructure for intercepting and mining asteroids, Planetary Resources expects to be able to help in the (slight) redirection of these rocks to keep the Earth safe," Peter Diamandis, the company's co-founder and co-chairman, said in a blog posting.
• Another commercial space-mining venture, Deep Space Industries, is proposing its own set of asteroid-hunting space telescopes. "Placing 10 of our small FireFly spacecraft into position to intercept close encounters would take four years and less than $100 million," David Gump, the company's CEO, said in a statement. "This will help the world develop the understanding needed to block later threats."

More about asteroids and meteors:

• Meteor? Asteroid? Terms get tangled
• Russian meteor blast outshone the sun
• System to vaporize asteroids is in the works
• NBCNews.com archive on asteroids

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

What exactly fell on Russia's Chelyabinsk region on Friday? Was it an asteroid, meteor, meteoroid, meteorite or fireball? You could make a case for "any of the above," depending on your definitions and the precise part of the phenomenon you're trying to describe.

The Chelyabinsk incident is the biggest known cosmic impact since another Russian blast that occurred a century ago, the Tunguska incident of 1908. There's good reason for that notoreity: Hundreds of injuries were reported. NASA estimated that the energy released by the Chelyabinsk impact amounted to 300 kilotons of TNT, which suggests the blast was more than 10 times as powerful as the atom bombs that were dropped on Japan at the end of World War II.

NASA's assessment put the Chelyabinsk object's width at 15 meters (50 feet), and its mass at 7,000 tons. Much of that mass burned up during the object's atmospheric entry at a velocity of 40,000 mph (18 kilometers per second). "The fireball was brighter than the sun," the space agency said in a statement.

Astronomers use different terms to describe cosmic objects of different sizes: When the rock is no wider than a meter (3.3 feet), it's known as a meteoroid. But once you start getting into the 1- to 10-meter range, the term "asteroid" applies. Earlier estimates suggested the Chelyabinsk object was a meteoroid, but the latest assessment would put it in the class of a small asteroid.

Bill Cooke, who heads the Meteoroid Environment Office at NASA's Marshall Space Center, said the object was "a small asteroid or a large meteoroid, depending on how you want to define it."

When pieces of the meteoroid (or asteroid) survive their fiery fall through the atmosphere and hit the surface, those pieces are called meteorites. Russian authorities say a hole in the ice on Chebarkul Lake, near Chelyabinsk, marks a spot where at least one meteorite left its mark. There are already reports of Chelyabinsk meteorites turning up on online auction sites, but those are more likely to be "meteor-wrongs" — rocks wrongly assumed to be meteorites.

Slideshow: Meteorite showers in Siberia

Yekaterina Pustynnikova / Chelyabinsk.ru via AP

A huge meteor flares through the skies over Russia's Chelyabinsk region, triggering a powerful shock wave that injured nearly a thousand people, blew out windows and reportedly caused the roof of a factory to collapse.

Launch slideshow

The term "meteor" refers to the fiery aerial display created by a falling meteoroid or asteroid. Meteors are called fireballs if they shine brighter than the planets in the night sky (magnitude -4), and bolides if the blast is even brighter (around magnitude -14). There's no question that the Chelyabinsk meteor qualifies as a bolide.

Some asteroids are made of iron and nickel, and survive their fall more easily. However, the fact that the Chelyabinsk object appeared to break up into pieces while it was still miles high indicates that it was made of less dense stuff. The stresses of atmospheric entry caused the rock to break apart explosively, creating the midair flash and generating a shock wave. The shock wave produced the loud "bang" that set off car alarms, blew out windows and apparently collapsed the roof of a zinc factory warehouse. Flying glass from all those broken windows caused many of the injuries that were reported.

What about the asteroid flyby?
The Chelyabinsk object streaked through Russian skies just hours before a 150-foot-wide (45-meter-wide) asteroid known as 2012 DA14 was due to make a remarkably close approach, coming within 17,200 miles of Earth's surface. However, the two objects were in dramatically different orbits, and that's one of the factors that led NASA to conclude that the two cosmic events were "not related."

"It's clearly coincidental, but it's a pretty amazing coincidence," said former Apollo astronaut Rusty Schweickart, a co-founder of the B612 Foundation. For years, Schweickart and his colleagues have been trying to raise awareness about the hazards posed by asteroids, and Friday's double dose of cosmic reality certainly serves as a consciousness-raiser.

"It's a torpedo across the bow," Schweickart told NBC News, "and it serves as an indication that these things really do happen."

Objects as small as the Chelyabinsk asteroid are difficult to detect — but the feat is not impossible, given the right circumstances. In 2008, a 2- to 5-meter-wide asteroid known as 2008 TC3 was spotted using the Catalina Sky Survey 1.5-meter telescope in Arizona, 20 hours before its impact in the Sudanese desert. The Chelyabinsk object would have been particularly hard to spot because it came in from the blind spot on Earth's sunlit side.

The Chelyabinsk object is no more, but there are still lots of other space rocks to be found. In 2011, NASA estimated that there are a million potentially hazardous near-Earth asteroids smaller than 100 meters (330 feet). Several organizations — including NASA, the B612 Foundation and Planetary Resources — are working on plans to detect and track more of the threats that are out there. To learn more about those efforts, click on the links below:

• Asteroid activists seek funds for space telescope
• Asteroid mining venture starts with space telescopes
• Asteroids vs. comets: NASA expert assesses threats

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Fri Feb 15, 2013 1:34 PM EST

Asteroid 2012 DA14 has made its closest pass of Earth, just a scant 17,200 miles from our surface, and now astronomers are watching it recede harmlessly into the cosmos. You can watch it, too, thanks to a variety of webcasts.

The time of closest approach came at 2:25 p.m. ET, as scheduled, when the asteroid was zooming above the eastern Indian Ocean at a speed of almost 17,500 mph (7.8 kilometers per second). It was too dim to see with the naked eye, but observers in Australia, Asia and Europe could follow it with binoculars or small telescopes.

"It's on its way out now," said Paul Chodas, an astronomer with the Near-Earth Object Program Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif.  

Read: Meteor vs. asteroid? Terms get tangled when describing space rocks 

Chodas and his colleagues monitored 2012 DA14 with high-powered optical telescopes and huge radar dishes to learn more about the asteroid's color, shape, spin and reflectivity. Such data could tell them what the object is made of, and perhaps provide insights into how similar objects could be diverted if they were on a threatening course.

Experts estimate that asteroids the size of 2012 DA14 hit our planet every 1,200 years or so, exploding with the energy of a 2.5-megaton atomic bomb: The last such impact struck a remote region of Siberia without warning in 1908, flattening 820 square miles of forest. If an object that big were to hit in just the wrong place, it could wipe out a city. Coincidentally, a much smaller space rock came down over Russia on Friday, sparking a fireball and a glass-shattering shock wave.

Even though the 150-foot-wide (45-meter-wide) asteroid 2012 DA14 is the biggest object of its kind to be seen coming this close to Earth, its orbit is so well-known that NASA's Near-Earth Object Program can rule out any chance of collision in the foreseeable future. And even though 2012 flew 5,000 miles closer than satellites in geosynchronous orbit, NASA said its mostly south-to-north orbital path went through a "sweet spot" that kept it far away from those satellites — as well as from other spacecraft that are in closer orbits, including the International Space Station.

Astronomer hope their observations of 2012 DA14 will provide insights into subtle phenomena such as seismic disturbances that are induced by Earth's gravitational kick, or characteristics of the asteroid's spin that are affected by radiation absorption and emission.

This animated set of three images shows 2012 DA14 as it was observed by the Faulkes Telescope South in Australia on Feb. 14 at a distance of 465,000 miles. The asteroid is the moving bright spot in the middle. NASA's website provides details. Credit: LCOGT / E. Gomez / Faulkes South / Remanzacco Observatory.

Radar readings provide the best way to get a fix on the asteroid's shape and spin, in part because observations from multiple radio telescopes can be combined to produce a clearer picture. During the 2012 DA14 encounter, scientists used radio telescopes in California and New Mexico to produce new sets of radar imagery.

The first pictures from NASA's 230-foot (70-meter) dish at Goldstone, Calif., are due to be released on Saturday, and eventually those radar images will be combined to produce a 3-D map of the space rock.

Other telescopes, spread out from Australia to Israel to the Canary Islands to the U.S., gathered optical data — and the images from some of those telescopes were shared over the Internet on Friday. NASA's Jet Propulsion Laboratory has been passing along pictures from a variety of telescopes via its Ustream video channel. Here's a rundown of other post-encounter webcasts:

5 p.m. ET: The Virtual Telescope Project 2.0 presents live video of the asteroid flyby from a telescope in Italy, weather permitting. Video site: Watch Virtual Telescope Project's webcast.

6 p.m. ET: Weather permitting, the Clay Center Observatory in Massachusetts will stream real-time, high-definition video from 6 p.m. ET until 4 a.m. ET Saturday. Watch Clay Center video on Ustream.

9 p.m. ET: Slooh Space Camera plans to present several live shows about the asteroid flyby, accompanied by expert commentary. Weather permitting, imagery will be beamed to Slooh HQ from telescopes on the Canary Islands and in Arizona. Watch the show on Slooh.com.

9 p.m. ET: A video feed of the flyby from a telescope at NASA's Marshall Space Flight Center will be streamed for three hours. During the live-streaming event, viewers can ask researchers questions about the flyby via Twitter or the Ustream chat window. Watch Marshall's Ustream channel.

Chodas said the initial observations confirmed scientists' estimates of 2012 DA14's size, but other revelations will have to wait until astronomers have had a chance to analyze the data collected on Friday. By that time, the asteroid will be long gone. Earth's gravitational influence has changed 2012 DA14's orbit to keep it farther away from our planet during future orbits.

"It won't return for many, many years," he said.

More about the asteroid encounter:

• How 2012 DA14 rates among asteroid hits and misses
• Would-be miners say asteroid is worth $195 billion
• Hooray! Earth will kick asteroid into a safer orbit
• Flash interactive: Close encounters of the asteroid kind
• NBCNews.com's archive on asteroids

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Fri Feb 15, 2013 7:51 AM EST