Film director Duncan Jones has developed a knack for sci-fi movies with mind-blowing twists, such as "Moon" and the just-released sci-fi thriller "Source Code." Just as "Moon" is more than a space movie, "Source Code" is more than a time-travel movie — but explaining why would totally give away the mind-blowing twist.

Let's just leave it at this: A combat vet is brought in to relive the last eight minutes leading up to a terrorist bombing of a train ... over and over again, a la "Groundhog Day." As in the Bill Murray movie, the main character (Jake Gyllenhaal) eventually learns how the time-recycling code works. The twisty plot draws upon a grab bag of speculative ideas from neuroscience, artificial intelligence and quantum physics, including:

• Near-death experiences: Brain activity continues even after the heart stops beating, and that may explain the out-of-this-world experiences that many people have reported when they're close to death's door.
• Neural reverse engineering: Some futurists suggest that computers will become advanced enough by the year 2045 to replicate the activity of the human brain. "People like Ray Kurzweil have suggested that one day, if we can actually map out the human brain and how it works, we could take one person's consciousness and transport it into another's," Jordan Wynn, the producer of "Source Code," says in the video clip above.
• Alternate realities: If you could travel back in time, could you make a course correction? Some physicists (such as Sean Carroll) say the flow of events from the past into the future is immutable, while others (such as Michio Kaku) say quantum physics allows for alternate realities. "We physicists believe that the river of time can fork into two rivers," Kaku said.
• Virtual reality: The tools for interacting with virtual worlds are getting better and better. "Within a few decades, we'll have workers, controlled by people with helmets, performing dangerous tasks — maybe at some point even extracting information from the parallel universe," Kaku said.
• Phantom consciousness: The brain can latch onto whole-body simulations so completely that it feels as if you are the simulation. That's the idea behind the "Matrix" movies, but it's also been tested in a series of experiments that led human subjects to feel as if they had three arms.

In the film, all these threads are woven together into a military research program called "Source Code."

But there's such a thing as too much science in science fiction: When Duncan Jones took on the project, he trimmed back the screenplay's geek factor, and emphasized the action and the interplay of characters instead. "I thought that if it was taken too seriously, and we dedicated too much time to the science, it would detract from the film's rip-roaring ride," the 39-year-old director told Time Out London. "So the rewriting I did was mostly to do with the tone."

Will "Source Code," with a Hollywood-sized budget of $35 million, make as much of an impact as "Moon," with an indie-sized budget of $5 million? That's something that time and the box-office tally will decide. But it's already clear that Jones, the son of rock star David Bowie, is finally in the spotlight on his own. Jones was named Zowie Bowie at birth, but he changed his name to distinguish himself from his dad (and maybe cut down on the snickers over being called "Zowie").

Jonathan Wenk / Summit Entertainment

"Source Code" director Duncan Jones (center) works with Jake Gyllenhall and Michelle Monaghan while filming a scene.

In an interview this week, Jones reflected on his past, present and future sci-fi movies as well as the Bowie factor. Here's an edited transcript:

Cosmic Log: Between this movie and "Moon," you're making a name for yourself as someone who takes on weird science-fiction concepts and turns them into watchable movies. How do you make the science just understandable enough to work?

Duncan Jones: For me, science-fiction movies are divided into two camps: hard sci-fi and soft sci-fi. With hard sci-fi, when you can see how the world can evolve into the science-fiction setting, sometimes it's useful to find ways to explain and put in that exposition, so the audience can really see how the world might change. But when you're into soft sci-fi, or in a gray area in between ... and I think time travel and those kinds of stories do fit in that gray area ... it's much more important that you ask the audience to take a leap of faith. You say, "Here are the rules we're going to set up. We'll play fair by those," and you just kind of leap on board.

In "Source Code," we manage to inject humor into the script and keep the tone light, and I think that allows the audience to feel OK about just accepting the rules and going along with it.

Q: Were there ideas you brought to the table thanks to your own familiarity with science-fiction themes, or scientific concepts you've absorbed through the years?

A: There was a certain amount of trying to create a realistic scenario ... whether it's the DARPA program or some other program in the Department of Defense, where you would imagine that this is a program that they don't necessarily fully believe in, but they want to see whether it's possible. They would invest a certain amount of money and give a professor some space and some financing to see whether it would actually work. My approach in the film was to treat the "Source Code" almost like high-end graduate-level work. It's a temporary facility, and if they prove themselves and it actually works, then all of a sudden they're going to get a huge infusion of Defense Department cash and be able to set up a facility that's specifically for "Source Code."

Q: As you were making the movie, are there books that you read or experiences that you had to give you a sense of how that science is done?

A: Ben Ripley [the screenwriter] was the one who did a lot more research on that end. I believe his wife is a scientist. He's surrounded by that world. On my side, I was a graduate student in philosophy, so I'm not really that close to the sciences. The work that I was doing in graduate school was on something called the mind-body problem, the idea of "what is consciousness." Whether it's a material thing, or whether there's anything beyond that. So a lot of the people I was dealing with were working in clinical psychology, for example. Some of them were working on direct brain manipulation with primates. Not in anticipation of this film, but in my past life, I had a sense of what works in graduate programs when it comes to brain studies.

Q: That's one of the most intriguing aspects of the film ... whether you can map the information from someone's brain into somebody else's brain. As a former philosophy student, or as a film director, do you have any thoughts on that subject?

A: The Directors Guild of America has recently been running a series of panels and lectures presented by scientists from various branches, to talk about the state of the art in their own disciplines. It's been incredibly fascinating and a real revelation to me, how many of the things that might at first appear to be science fiction are, if not actually happening, certainly being brought closer to reality.

I'm sure you've read about the retinal implant that allows a 60-pixel image to be seen by someone who was previously completely blind, allowing them to read and see movement in front of them. There's robotics work that has allowed a scientific program to replicate the movement of a lungfish through water, using electrical impulses to sense where prey might be around them. There's another program about a beetle that goes through metamorphosis, and when the bug finishes metamorphosizing, scientists can remote-control the beetle's flight around the room. The science fiction in our film is certainly incredibly exciting, and a great concept for a movie, but who knows how close we are to some of the ideas that we talk about?

Summit Entertainment

A combat vet (Jake Gyllenhaal) takes on an unorthodox counterterrorism assignment in the film "Source Code."

Q: In "Moon," the plot gets inside the main character's head, but the movie felt as if it had a realistic outcome. "Source Code" goes farther into the speculative sphere. Nobody wants to give the plot away, but there's a big twist. How do you deal with those big twists? Or do you put the science aside and say it just feels right dramatically?

A: It's funny, because although "Moon" is more science-fiction in some ways ... it's based on the far side of the moon in the future, while "Source Code" is contemporary ... in other ways it's more hard sci-fi. "Moon" is based on Robert Zubrin's book, "Entering Space," all about how helium-3 mining might hypothetically work, and why one might want to acquire helium-3 in the first place, for fusion reactors. In my mind, "Moon" is based on a much more concrete foundation scientifically.

For "Source Code," Ben Ripley did a lot of the research himself. And without getting too much into spoiler territory, I think the nature of ... not so much time travel, but travel into parallel realities is something which is hypothetically very interesting. It certainly has its own rules which it abides by. Now, whether that theory is justified ... that's a question. With "Moon," you can see how science could get us to the point where we would be mining helium on the moon. With "Source Code," the movie demands that you take this theory seriously and believe that access to parallel realities is possible.

Q: I've read that you have another science-fiction project that you're thinking about. Could you say something about that?

A: I am writing what I'm hoping is going to be my next film, and it's a science-fiction film. It's more hard sci-fi in some ways, but it's very heavy on the action. I'm trying to invest it with the same level of believability as the early James Cameron works. You look at something like "Aliens," where you get a sense of how the mechanics of that world works. I can't say much about it, except that it's a good middle ground between "Source Code" and "Moon."

Q: Any recommended reading for fans who want to get ready for the film?

A: It certainly fits within the world of Philip K. Dick. He and J.G. Ballard are probably the two authors who have most excited me in my science-fiction reading throughout my life, and it's always been my dream to actually make a film that captures the essence of what I love about those two particular writers.

Q: How is life after "Moon"?

A: There really hasn't been much opportunity for me to get a sense of how everything changed, because literally off the tail end of the press that I was doing for "Moon," I found myself having to immediately go up to Montreal to begin work on "Source Code." I moved to Los Angeles to complete the post-production, and ever since I've been working on the release of "Source Code." I'm only just now getting to the point where I'm getting a sense of what it all means.

Q: And finally, let's talk about the David Bowie question. It seems as if you are coming out of the shadow cast by your famous father. How do you feel about that? Do you feel that you're finally being taken seriously as your own person, or do you feel that you really want to hang onto that connection with what your father has done?

A: I think I'm getting there. Hopefully I'll get to the point where it's an interesting fact, but not the focus of any interview or article about what I'm doing. I completely get it. I understand why it is of interest. But I look forward to the day when I get to remind people who my dad is.

More about the science in science fiction:

• Why we love to fear E.T.
• The physics behind the movie magic
• Virtual actor takes over in 'Tron'
• How much real science is in 'Avatar'?
• When science meets fiction

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about my book on Pluto and the search for planets, check out the website for "The Case for Pluto."

Sukree Sukplang / Reuters

An official from Thailand's Food and Drug Administration takes a sample from a shipment of frozen fish imported from Japan to test for possible radiation contamination at a customs station in Bangkok today.

Experts say that fish and other marine species shouldn't be as affected by Japan's nuclear crisis as species on land, in part because of differences in the ways radiation is dispersed.

But that doesn't mean authorities can ease up on monitoring the sea and its bounty for contamination. To the contrary: Inspectors around the world are keeping a close eye on food imports from Japan, and some countries have ordered special inspections or even outright bans on fish coming from areas near the plant.

Twenty days after Japan's earthquake and tsunami touched off a breakdown and partial meltdown at the Fukushima Dai-ichi nuclear complex, some radiation experts are still struggling to get an accurate read on the situation.

"My basic feeling is that they're going to come to grips with this, and at the end of the day, it's not going to be as bad as people fear," said Florida State University oceanographer William Burnett, an expert on the environmental effects of radioactivity. "Having said that, trying to follow this story has been difficult. I see almost no real data."

The most reliable measurements have been coming from the International Atomic Energy's daily updates on the situation, said Andrew Maidment, a professor of radiology and chief of the physics section at the Hospital of the University of Pennsylvania. So get ready for some real data.

The latest fish radiation readings are above background levels, but still nowhere near the safety limits. The highest radiation reading for fish from the Japanese port of Choshi was 3 becquerels per kilogram of cesium-137 — far below Japan's limit of 500 becquerels per kilogram, or Bq/kg.

"This confirms what scientists including myself have been saying: First of all, the water will dilute this, and the uptake will therefore be lower than it would be for a terrestrial animal," Maidment told me. "The greater the volume of water, the higher the dilution, and the lower the impact."

When radioactive fallout is dispersed on land, it collects on what is essentially a two-dimensional carpet of vegetation, to be ingested later by livestock or humans. But when the fallout reaches the sea, it's dispersed in a much deeper three-dimensional space.

Maidment said this phenomenon was seen clearly in the wake of the 1986 Chernobyl disaster, which still ranks as more of an environmental catastrophe than Fukushima: Wild boars that were tested within a 30-kilometer radius of the Chernobyl site registered 470,000 Bq/kg of cesium-137, while freshwater perch showed concentrations of 4,000 Bq/kg. Eight years later, the levels were reduced to 5,000 Bq/kg for the boars, and 200 Bq/kg for the perch. Even those levels are unpalatably high, but they illustrate Maidment's main points: Marine life tends to absorb less radiation, and contamination levels go down over time.

Yardsticks for radiation
Let's take a moment to talk about the radiation standards: When we're talking about the absorbed dose for humans, that tends to be expressed in terms of millisieverts. For example, the typical annual radiation dose from natural sources amounts to roughly 3 millisieverts.

But when we're talking about the radioactivity contained in various substances, the standard measure is becquerels per kilogram or per liter. The safety standards vary according to what type of radioisotope we're talking about, the type of substance we're talking about, and the type of person who might come in contact with that substance. That's because there's a wide range of variation in the uptake of radioisotopes and their effects on the body.

Here are the safety limits set by Japan's Food Safety Commission and reported by Bloomberg:

• Iodine-131: 300 Bq/kg for drinking water, milk and dairy products. 2,000 Bq/kg for vegetables except for root vegetables and tubers.
• Radioactive cesium: 200 Bq/kg for drinking water, milk and dairy products. 500 Bq/kg for vegetables, grains, meat, eggs and fish.
• Uranium: 20 Bq/kg for infant foods, drinking water, milk and dairy products, 100 Bq/kg for vegetables, grains, meat, eggs and fish.
• Alpha-emitting nuclides of plutonium and transuranic elements: 1 Bq/kg for infant foods, drinking water, milk and dairy products. 10 Bq/kg for vegetables, grains, meat, eggs and fish.

Materials exceeding 100 Bq/kg should not be used as the basis for powdered infant milk formula.

Close to the Fukushima plant, the radiation levels are alarming: The IAEA said samples of seawater collected 330 meters east of the nuclear complex's discharge point showed iodine-131 concentrations of 74,000 becquerels per liter, roughly equivalent to Bq/kg. The cesium levels were 12,000 Bq/kg for cesium-137 and another 12,000 Bq/kg for cesium-134. But those levels drop sharply with distance, due to the dispersion factor.

Radioactive iodine-131 is a huge concern for people living around the Fukushima plant, because that can be quickly taken up into the thyroid and pose a significant cancer risk. What's more, iodine is taken up readily by seaweed, which is a popular food item in Japan. Elevated (but still safe) levels of radioactive iodine have been detected in seaweed as far away as Vancouver, and in milk samples from Spokane, Wash. (The reading for the milk was 0.8 picocuries per liter, or roughly 0.03 Bq/kg.)

The flip side is that iodine-131 has a relatively short half-life of eight days, so as time passes, the iodine risk should drop significantly for fish as well as for people.

Cesium-137 has a longer half-life (30 years), so it poses a longer-lived threat. The fish tests suggest that the cesium radiation levels are just one-tenth of the iodine levels, Maidment said.

Stay focused on the fish
Authorities will have to be extra-vigilant about watching radiation levels from Fukushima for a long time — on the ground, in the air and at sea, said Edwin Lyman, a senior staff scientist at the Union of Concerned Scientists, an activist group.

"Even dilute levels of contamination can be enhanced in certain marine life, you know, just like mercury concentrates in large fish, like tuna," he told reporters during a briefing on Monday. "Also, plants like seaweed are known to concentrate certain isotopes, and so are certain types of shellfish. But I would think certainly in the fishing industry in the region, they're most likely going to have to take measures to inspect their catches, and I guess the primary responsibility for that will have to be with the Japanese to inspect and interdict any contaminated seafood."

Maidment agrees that more monitoring will be needed. He also suspects that shellfish living on the seabed around Fukushima might face more contamination than the fish that just happen to migrate through the seas near the stricken plant. But he says "it's too early to draw conclusions," and he emphasizes that the general public needs to put the radiation issue in perspective.

For example, suppose that your drinking water contained 100 becquerels per liter, which is basically 100 Bq/kg. "If that water constituted 10 percent of your dietary intake of food, by weight, and you consumed that exclusively per year, you would increase your background radiation by about 20 percent," Maidment said. "I can double my background radiation just by moving from Philadelphia to Denver. So these are levels of radiation that most of us are not aware of."

I'm betting that you're more aware of the radiation issue than you were 20 days ago, and that you have some thoughts you'd like to share. Feel free to weigh in with your comments below.

Update for 12:55 a.m. ET March 31: One of my Facebook friends, Lynda Williams (the Physics Chanteuse), points out that I have not actually defined what a becquerel is. One becquerel is a unit of radioactivity that's equal to one nuclear decay per second. Here's the way she put it: "It is one atom of a radioactive isotope decaying and emitting radioactive decay. So 5,000 Bq/kg means that 10,000 atoms are decaying per second and shooting off a particle per second in one kilogram. So if the pig has a mass of 100 kilograms, we are talking about a whole body exposure of — do the math, 500,000 particles shooting through its body every second. The 'data' means more if you explain what it really means." Thanks, Lynda!

More angles on radiation:

• Seattle physicists detect radioactivity, fear it'll wreck experiment
• Japanese evacuees' new woe: Radiation prejudice
• World Blog: Tokyo fishmonger fears more radiation leaks
• Cosmic Log recap on the disaster in Japan
• Msnbc.com's special report on the disaster

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about my book on Pluto and the search for planets, check out the website for "The Case for Pluto." 

Gary W. Meek / Georgia Tech file

Georgia Tech Professor Zhong Lin Wang holds a prototype nanowire array that could be used to power nanometer-scale devices. Wang and his colleagues say they have developed a commercially viable version of the nanogenerator.

Someday, your pulse could provide all the power you'll need for your iPod. At least that's the promise held out by researchers who say they've developed the first commercially viable nanogenerator.

The nanogenerator is actually a flexible chip containing millions of zinc oxide nanowires. The important thing about these wires is that when you flex them, they create a tiny bit of electric current. This phenomenon, known as the piezoelectric effect, was discovered more than a century ago and plays an essential role in lots of electronic devices.

Suppose you could deposit millions of power-generating nanowires in just the right arrangement, within layers of polymer material, and suppose you could flex them in just the right way to capture and combine the resulting electricity. That's what Georgia Tech's Zhong Lin Wang and his colleagues have been working on for the past six years.

Their latest prototype chips are about a quarter the size of a postage stamp, but when you stack five of the chips on top of each other like a sandwich, you can produce 1 microampere of current at 3 volts — which is equivalent to the voltage of two AA batteries. And you can produce it just by squeezing the chips together with your fingers.

That's enough power to light up an LED bulb or a liquid crystal display on a calculator or computer.

"While a few volts may not seem like much, it has grown by leaps and bounds over previous versions of the nanogenerator," Wang said in a news release from the American Chemical Society. "Additional nanowires and more nanogenerators, stacked together, could produce enough energy for powering larger electronics, such as an iPod or charging a cell phone."

Zhong Lin Wang / Georgia Tech

When the nanogenerator chip is flexed between the fingers, it puts out enough power to light up an LED bulb and an LCD display.

During a presentation at this week's ACS national meeting in Anaheim, Calif., Wang said the latest device puts out thousands of times more power and 150 times more voltage than the early prototypes.

"This development represents a milestone toward producing portable electronics that can be powered by body movements without the use of batteries or electrical outlets," he said. "Our nanogenerators are poised to change lives in the future. Their potential is only limited by one's imagination."

If Wang were merely talking about charging up iPods by pinching your fingers together, that wouldn't create much of a stir. But he suggests that piezoelectric nanogenerators could be placed into the soles of your shoes to power up wearable electronic devices (fitness monitors, for example). They could be implanted inside the body, using the energy of your heartbeat to keep an insulin pump going. They could be woven into wind-powered environmental sensors that flap in the breeze, or built into the automotive tires to produce an extra jolt of electricity for your car's accessories.

But all those applications are still a little farther down the road. Wang and his colleagues still have to find a way to make further improvements in power output, and then find a company to produce the devices commercially. Wang estimates that the first nanogenerators will make their appearance on the market in the next three to five years, most likely as power sources for environmental sensors or infrastructure monitoring devices.

More about tiny power sources:

• How Wang's device could power micro-robots
• Micro-motor runs on bacteria power
• Transistor merges man and machine
• Could sperm power nanobots?

Funding for the nanogenerator research comes from the Pentagon's Defense Advanced Research Projects Agency, the U.S. Department of Energy, the National Institutes of Health, the National Science Foundation and the U.S. Air Force.

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about my book on Pluto and the search for planets, check out the website for "The Case for Pluto." 

NASA / JHUAPL / CIW

The first image sent back to Earth from Mercury orbit shows a rayed crater known as Debussy and a smaller crater with unusual dark rays, called Matabei. The picture was transmitted to Earth by NASA's Messenger spacecraft.

Last updated 3:40 p.m. ET March 30:

NASA's Messenger mission unveiled the first picture of the planet Mercury taken by an orbiting spacecraft on Tuesday, and promised to provide more goodies in the days and months to come.

The picture shows a wide region of Mercury's southern hemisphere, including the south pole and a wedge of the planet that has never been photographed close-up before. But you'd probably be forgiven if you wondered whether the Messenger probe was orbiting the moon rather than Mercury: The monochromatic, heavily cratered terrain looks a lot like the lunar surface.

Here's a description of the scene from Messenger's science team:

"The dominant rayed crater in the upper portion of the image is Debussy. The smaller crater Matabei with its unusual dark rays is visible to the west of Debussy. The bottom portion of this image is near Mercury's south pole and includes a region of Mercury's surface not previously seen by spacecraft. Compare this image to the planned image footprint [displayed below] to see the region of newly imaged terrain, south of Debussy."

NASA / JHUAPL / CIW

The yellow square on this mosaic image shows the planned footprint for the first image to be acquired by a spacecraft orbiting Mercury. The dark area represents a region of the planet that has not previously been seen by spacecraft.

Messenger's science team is already familiar with most of Mercury's terrain. The $446 million mission got under way in 2004, and the desk-sized probe zoomed past Mercury in 2008 (twice!) and in 2009. At its closest, Messenger came within 124 miles (200 kilometers) of the surface, which is much closer than the distance from which today's picture was taken (about 9,500 miles or 15,000 kilometers).

But Messenger (whose name comes from the acronym for MErcury Surface, Space ENvironment, GEochemistry and Ranging) wasn't in orbit back then. It was just passing through. The probe finally entered orbit around Mercury on March 17 and is now going through its commissioning phase.

The Messenger mission's principal investigator, Sean Solomon of the Carnegie Institution of Washington, said in a news release that he and his colleagues were "thrilled that the spacecraft and instrument checkout has been proceeding according to plan":

"The first images from orbit and the first measurements from Messenger's other payload instruments are only the opening trickle of the flood of new information that we can expect over the coming year. The orbital exploration of the solar system’s innermost planet has begun."

Today's picture, snapped at 5:20 a.m. ET, was the first of 364 images that were acquired during a span of six hours and sent back to Earth, Messenger's mission team said. More than 1,000 images are due to be taken during the probe's checkout. During Messenger's yearlong science campaign, more than 75,000 pictures are to be sent back.

Mercury has been studied during flybys before, most notably by Mariner 10 in 1974-75, but Messenger is the first spacecraft to orbit the solar system's innermost planet. It's also the densest planet, as well as the planet with the largest daily variations in surface temperature.

Just how big is Mercury's metal-rich core? Do deep, permanently shadowed craters at the planet's poles contain ice? What does its atmosphere (or "exosphere") contain? Why does Mercury have a global magnetic field, while Venus and Mars do not? Messenger's team plans to address all those questions in the year ahead. Some of them may even be addressed on Wednesday, when team leaders are due to discuss Messenger's first images at 2 p.m. ET during a NASA teleconference. Stay tuned for updates after the scientists have had their say. 

Update for 3:40 p.m. March 30: Still more pictures were released on Wednesday, as promised. Check out this Photoblog gallery featuring three of the best images, and check back later for still more about the successful start of Messenger's orbital mission.  

More about Mercury:

• 10 surprising facts about Messenger
• Is Mercury an incredible shrinking planet?
• Mercury just might hit us someday
• Interactive: The new solar system

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about my book on Pluto and the search for planets, check out the website for "The Case for Pluto." And if you want to stay on my good side, don't ever call Mercury the "smallest planet."

NASA Kepler via Jason Rowe on Flickr

This graphic shows the 1,235 candidate planets reported so far by NASA's Kepler mission, in proportion to their parent stars. For comparison's sake, our own sun is shown as well. It's just below the top row on the right, with Jupiter and Earth silhouetted against the disk. Click on the image to see larger versions on Flickr.

Two years after its launch, NASA's Kepler space telescope has detected more than 1,200 potential planets circling distant stars by tracking the slight dimming of starlight. This graphic, drawn up by Kepler science team member Jason Rowe, shows all 1,235 worlds in proper proportion to their respective stars. Some of the stars are thought to have multiple planets. To spot them all, you'll have to check Rowe's Flickr page for higher-resolution views.

The stars' sizes range from 6.1 times larger than our sun to just a third as wide. For comparison's sake, Rowe has included our own sun, off by itself beneath the top row. Jupiter appears as a speck in silhouette, and Earth is an even more minuscule speck. The colors of each star reflect how it would look if we could see it up close, outside Earth's atmosphere.

Nearly all of these candidates have yet to be confirmed as planets rather than binary-star companions or computer glitches. Kepler's scientists expect that 80 to 90 percent of them will turn out to be honest-to-goodness exoplanets. They also expect to find plenty more candidates as the mission continues, including some specks as tiny as Earth.

Check out these marvels from Kepler's planetary menagerie:

• Planet probe spots hot prospects
• Oops! Hopes for alien Earth go poof
• A tourist's guide to the Kepler-11 planetary system
• Planetary six-pack poses a puzzle
• Probe finds planetary missing link
• Planets spotted in changing orbits
• Planet-hunter finds five lightweight worlds
• Kepler snaps its first images

So what about our own planetary neck of the woods? A few years ago, Kokogiak blogger (and former MSNBC colleague) Alan Taylor drew up a similar graphic showing the relative size of all known solar-system bodies that are wider than 200 miles. It's a pretty wide array. Click on the thumbnail graphic below to see the full-size display, and explore our "New Solar System" interactive to learn more about the solar system's lineup.

Alan Taylor / Kokogiak

This graphic shows all known solar-system bodies wider than 200 miles. Click on the image to see larger versions.

Tip o' the Log to Discovery News' Ian O'Neill and Astronomy Picture of the Day.

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto." 

Jabulani Barber and Ludovico Cademartiri / Harvard

A methane flame shooting out from a burner is deflected by a wire electrode. Moments later, the flame went out.

Last updated 10:15 p.m. ET:

Researchers say they've found a new way to snuff out flames using an electric field-generating wand — and the seemingly magical technique just might be put to use in future fire rescues.

"What we are excited about is that this presents a new capability in the control of flames," Harvard researcher Ludovico Cademartiri told me today.

Cademartiri presented a report on the flame-quenching method on Sunday at a national meeting of the American Chemical Society in Anaheim, Calif. He has been working on the technique as a member of Harvard Professor George M. Whitesides' research group, along with Penn State's Kyle Bishop.

The technology sounds a bit like the fictional flame-freezing charm or the Aguamenti spell mentioned in J.K. Rowling's series of Harry Potter books, and the fact that it's done with a wand-like electrode makes the story even better. "The best geometry of the electrode is in the form of a thin wire, which journalists creatively labeled a wand," Cademartiri said.

For two centuries, scientists have known that electric fields can interact with flames, but the effect from a continuous DC electric field was too small to have practical applications. "By applying oscillating fields, the effect was much, much larger," Cademartiri said.

In the lab, researchers set up a 600-watt amplifier — with about the same power as a high-end car stereo system — and hooked it up to the wand. Then they pointed the wand at the base of a methane-fueled flame emanating from the orifice of a burner. Cademartiri said the wand's electric field disrupted the flame and snuffed it out, even when the flame was cranked up to a height of 20 inches (50 centimeters).

"The electric field interacts with the charged particles in the flame — the electrons, ions and soot particles — and this collective motion of the charges in the electric field can lead to movement of the gas within the flame," Cademartiri explained. "The mechanics of suppression is that the flame gets detached from the fuel source, so it gets pushed away. This is somewhat different from blowing on the flame."

Bishop said that the flame-taming effect isn't all that noticeable at low voltages. "The one thing that is new is the ability to use large, time-varying electric fields. ... It's only been recently that the high-voltage power supplies that make this kind of perturbation possible have become commercially available," he told me.

In their most successful experiments, the researchers turned the dial up to 40,000 volts, Bishop said.

The research could eventually lead to the development a new gizmo for the firefighter's toolbox, in addition to tried-and-true methods such as water from fire hoses, powder from a fire extinguisher and flame-suppressing foam from a tank. In contrast with those methods, the electro-blaster does not need to put any material in contact with the flames themselves. Cademartiri imagines that such gizmos could be attached to the walls or ceilings of buildings or ships, or carried by a firefighter in a backpack. Electric wands could help fire crews open an escape path for people trapped in an enclosed space. However, Cademartiri noted that the system wouldn't be as suitable for quelling flames in open spaces, such as in the midst of a forest fire.

The Pentagon's Defense Advanced Research Projects Agency and the U.S. Department of Energy have been funding this research for a couple of years now, but the flame-freezing wand isn't ready for prime time yet.

"We want to really completely understand this interaction," Cademartiri said. "It's a novel thing. People have not seen it before, and it's really complex. ... The second thing is that we are starting to look at how these effects scale with the size of the flame."

Bishop said he and his colleagues were already getting ready to submit research papers to a number of scientific journals. "There should be publications forthcoming within the next six months," he said.

In the longer term, the technology could be applied not only to future rescues, but also to industrial applications ranging from better welding torches to more efficient automotive engines and power plants. "Ninety percent of our energy comes from combustion," Cademartiri noted.

All things considered, it sounds like a technology worth waiting for. Making combustion more controllable would add to a long list of advances that go all the way back to, well, the mastery of fire itself.

More about mastering fire:

• Firefighting safety equipment makes debut
• NASA eyes next-gen firefighting gear
• Slimy fire-retardant gel can save homes
• Burning issue: When did humans master fire?
• Chimps master first step in controlling fire

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto."

Courtesy of George Djorgovski

Second Life residents Desdemona Enfield and Curious George work on a virtual-reality visualization that classifies stars, galaxies and quasars according to their colors, brightness, distance and morphology.

Does the virtual-reality world known as Second Life have anything to offer for real-world scientists? Absolutely — and a trailblazing researcher says the payoffs are sure to increase when the Internet goes 3-D.

"We are really meant to interact in 3-D, with other people and with information," Caltech astronomer George Djorgovski, director of the Meta Institute for Computational Astrophysics, told me today during an interview in Second Life. "Because this works so well with the human perception system, as soon as there is an easy and 'good enough' 3-D approach, people will switch en masse."

Djorgovski will talk about the past, present and future of virtual worlds on "Virtually Speaking Science," a talk show that's simulcast in Second Life and on the Web via BlogTalkRadio. I'm one of the co-hosts of the hourlong show, which airs on Sunday at 7 p.m. SLT/PT (10 p.m. ET).

Virtual worlds have been around for decades, if you count immersive gaming environments such as World of Warcraft. But jacking into virtual reality still isn't exactly a mainstream phenomenon. Some might be scared off by the fact that online worlds can offer havens for cyber-sex and other virtual vices. Others might see Second Life as downright clunky, compared with the photorealistic, hyper-responsive graphics of present-day video games or the all-consuming interaction available through Facebook or Twitter.

But when it comes to scientific collaboration and outreach, Djorgovski thinks Second Life is a thick slice of awesome.

"This technology is already basically a killer app," he told me. "Even with its crappy graphics and user interface, it already works astonishingly well. And that's only going to get a lot better."

Djorgovski joined Second Life three years ago, and today his avatar ("Curious George") seems totally comfortable in the world. (I, on the other hand, still walk over chairs, even though I've been an occasional Second Lifer for four years.) The Meta Institute for Computational Astrophysics presents a series of professional seminars, workshops and popular talks in Second Life, including a couple that I've presented. In addition, Djorgovski regularly meets with scientific collaborators in Second Life to work on his real-world research, which focuses on galaxy formation and evolution, quasars, sky surveys and data visualization.

"Even if they're in Pasadena, we meet in Second Life," Djorgovski said of his colleagues. "We prefer doing that over Skype, even if it's just one-on-one. It feels better."

Why is that? Djorgovski points to a couple of analyses suggesting that immersive telepresence is more engaging than phone or video conferencing — partly because multiple senses (hearing, sight, kinesthetics) are in play, and partly because there's more of a sense of inhabiting 3-D space. But those advantages apply to any type of virtual-reality interaction. Djorgovski goes on to say that scientific applications in particular can be more fruitful because you can immerse yourself in your own data.

The road to virtual worlds
That's why he took up residence in Second Life to begin with. Djorgovski has long been interested in finding better ways to work with massive databases, such as the Palomar Digital Sky Survey he worked on back in the 1990s. "With sky surveys, we suddenly had so much informational wealth that it was actually irresponsible not to make the data public," he said.

Djorgovski played a part in articulating the concept of a "Virtual Observatory" that could be used by astronomers as well as the general public — a concept that gave rise to the National Science Foundation's National Virtual Observatory as well as Google Sky and Microsoft Research's WorldWide Telescope. (Microsoft is a partner in the msnbc.com joint venture.)

Djorgovski's not the only one interested in 21st-century tools for handling large data sets. "There is a worldwide community of aficionados of what is variously called e-Science, informational science or cyberinfrastructure," he said. "I would say there are about 1,000 researchers worldwide, and it's very much the start of an S-curve."

He compares the current situation to the situation that faced scientists in the 19th century, when the field of statistics was developed to handle kilobytes' worth of data. Djorgovski believes a new set of tools will be needed to cope with terabytes, petabytes and exabytes. "That's exactly what led me into this virtual-reality business," he said.

In a 2008 posting to the Cosmic Variance blog, Djorgovski describes how a couple of research papers written by Piet Hut, a stellar-dynamics expert at the Institute for Advanced Study, pointed him toward Second Life. "I was very skeptical ... until I tried it," Djorgovski told me. "Then I became a convert."

Today, Djorgovski's little corner of virtual property contains one 3-D simulation that charts categories of stars, galaxies and quasars, and another that lets you fiddle with gravity in triple-star systems.

Djorgovski said virtual worlds can offer opportunities for budding scientists as well as the professionals. "I can totally see that this would be a very powerful way to provide experimental experience to students who don't have access to a real lab," Djorgovski said. "Maybe it's not 100 percent fidelity, but if it's 90 percent, that's still better than zero."

You'll find plenty of virtual experiments in SploLand, the Second Life science center operated by San Francisco's Exploratorium.  "We're using it as an extension of our exhibit space, to do things for our online visitors that we can't do in the real world," Rob Rothfarb, the Exploratorium's project director for online engagement, told me today.

For example, Second Life visitors can shoot themselves out of a virtual cannon to learn about Newtonian orbital mechanics, visit the center of the big bang, or sit on top of an atom to feel the jiggles of Brownian motion.

They can also gather together in cyberspace to witness live events such as a total lunar eclipse. "In those cases, we're creating extensions of our public programs," Rothfarb said. "We're able to share exciting images, along with commentary from scientists, and we're creating a context for conversation among people who come there from all over the world."

Just last week, SploLand was the venue for the Exploratorium's Second Life celebration of Pi Day, the science-centered holiday that celebrates 3.14 as well as Albert Einstein's birthday.

Djorgovski said such events show that virtual worlds can make a valulable contribution to science education. "It's actually very impressive what goes on in the education community," he said. "We're thinking, 'OK, obviously what's happening is that people who can't come to Caltech or the Exploratorium can do this here in Second Life.'"

The future of virtual worlds
So what's next? Djorgovski said Second Life is still too limited to handle the kinds of high-data applications that scientists will require in the years ahead. He pointed to his own stellar-classification simulation and said, "If I were to put in another 12,000 data points here, it might crash the server."

The future may well lie in open-source virtual environments, created using tools such as OpenSim. Djorgovski can easily imagine an immersive 3-D version of Facebook, for example, or an interface that displays websites as objects in virtual 3-D space rather than as rectangles on a 2-D screen.

"To my mind, really, it has to be a full immersive 3-D version that draws upon content that's already on the Internet," he said. "Humanity's information content is all on the Internet now. We use it to access all kinds of information, to access each other, to access entertainment. That's not going to change. Whoever builds 3-D, immersive, virtual-reality environments will pretty much have to do it in a way that is entirely compatible with the mainstream cyberspace that we're using. It can be a year. It can be 10 years. But I'm confident that someday it will happen. I wouldn't be surprised if the immersive 3-D Web will be as fundamentally transformative as the Web itself."

What do you think? Weigh in with your comments below, and be sure to tune in to "Virtually Speaking Science" on Sunday. And if you miss the live show for some reason, never fear: It'll be made available as a downloadable podcast next week. 

More about virtual reality:

• Second Life Education Wiki 
• Virtual haven set up for combat vets
• Game device adapted for robo-touch
• Virtual puppies want to lick your real face

My co-host on "Virtually Speaking Science" is Robin Snelson of the Space Studies Institute. Check out these links for podcasts from previous shows:

• Tim Pickens, team leader of the Rocket City Space Pioneers, talks about commercial spaceflight and his team's bid to launch a lunar rover (Feb. 13).
• Air Force Col. M.V. "Coyote" Smith discusses the future of space solar power and private enterprise on the final frontier (Feb. 27).
• Planetary scientist Alan Stern of the Southwest Research Institute chats about suborbital space research as well as NASA's New Horizons mission to Pluto and the Kuiper Belt (March 13).

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto."

NHK via Reuters

Smoke rises from the nuclear reactors of Japan's Fukushima Dai-ichi nuclear power plant in an NHK video image from Thursday.

The battle to stabilize Japan's stricken Fukushima Dai-ichi nuclear complex just got tougher, due to the radioactive water that is apparently leaking from the reactors. The leak doesn’t change the battle strategy — to get water into the reactor buildings to stabilize "hot" fuel rods — but it does raise more uncertainties about how to get that done.

"The operators are having to do a lot of improvisation to figure out what best to do to keep the amount of radiation being released into the atmosphere to a minimum," nuclear engineering expert Elmer Lewis, a professor emeritus at Northwestern University, told me today.

The uncertainties currently focus on the leak, which exposed three workers wading through the water to so much radioactivity that they had to be hospitalized for radiation burns.

Some reports suggested that the skin radiation exposure amounted to 2,000 to 6,000 millisieverts. Exposure to that much full-body gamma radiation over the course of an hour would be deadly. However, in this case the burns were due to shorter-range beta radiation. The gamma radiation exposure was estimated at 170 to 180 millisieverts.

So where is that water coming from? "The data we're seeing is contradictory," said former nuclear engineer David Lochbaum, director of the Union of Concerned Scientists' nuclear safety project. It could be coming from the spent fuel rods stored near Fukushima Dai-ichi's Unit 3 reactor, or from the reactor vessel itself. The workers who came in contact with the water were working in the turbine room connected to Unit 3.

NBC News' Robert Bazell quoted outside nuclear engineers as saying that the water contained radioactive iodine-131, which could come only from the rods in the reactor's pressure vessel. That led some experts to say that the vessel was breached, but Lochbaum said that didn't mesh with the pressure readings being taken inside and outside the vessel.

"Either the pressure data we're seeing is inaccurate, or the breach isn't as serious" as some have claimed, Lochbaum told me.

If the water is leaking from the reactor vessel, it should still have been contained within the primary containment chamber that surrounds the vessel. However, there might be some sort of leak in the plumbing between the vessel and the Unit 3 turbine room. That's the scenario favored by Tom Crimmins, president at Executive & Nuclear Consulting. "There's a larger-than-expected leak somewhere in the system that's releasing this radioactive water," he said on MSNBC.

Whatever the cause, the leak is bad news for workers at the nuclear complex, "primarily because it makes working conditions there more difficult or potentially impossible," Princeton physicist Frank von Hippel said on MSNBC.

James Acton, a nuclear expert at the Carnegie Endowment for International Peace, said workers might have to pull back from the turbine rooms — not only at Unit 3, but at Units 1 and 2 as well, where elevated radiation levels have reportedly been detected. "Work in those areas is clearly going to be massively hampered, if not stopped entirely," he said, "but if radiation levels on the site as a whole don't rise, then work across the site can presumably continue."

Unit 3 is of particular concern, because that's the only reactor at the Fukushima site that uses a mixed uranium-plutonium fuel, also known as a mixed-oxide fuel or "MOX." But Lewis said some commentators are making too much of that distinction.

"Whenever you're burning uranium, you're always producing some plutonium," Lewis told me. "It's a matter of degree. The plutonium, like the uranium itself, is a ceramic element, and it's not very volatile at all. So I doubt seriously whether the water in the turbine room contains much if any plutonium. It tends not to be released except at very high temperatures. I think they're seeing fission-product radiation." (That is, radioactivity from elements such as iodine or cesium.)

Virtually all the experts are dismayed that the plant still hasn't been brought under control. "There's still too much energy coming out of that fuel to walk away," von Hippel said. "They still have to keep trying to cool it. The problem is that we're now two weeks after the accident started, and they don't have a handle on the situation yet."

The strategy remains the same as it has been for the past week: Make sure the fuel rods in the reactors as well as in the spent-fuel pools are covered with water and wait for the radioactivity in those rods to cool down.

Because Fukushima lacks electrical power to get water circulating through the reactors and the pools, workers have had to pump seawater into the works — and that could be creating a fresh round of problems, including corrosion in the plumbing and releases of radioactive steam. The prime objective right now is to get the standard water-cooling system working again.

"My own criterion for when I'll breathe easier is when they don't need seawater any more," Lewis said. So that means workers — or perhaps robots — will have to find a way to continue with the job of spraying water on the reactors, hooking up electrical power and regaining control of the nuclear battlefield.

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto."

Jessica Rinaldi / Reuters

Photos show the Empire State Building before and during Earth Hour in New York on March 27, 2010. Countries around the world have signed up for Earth Hour from 8:30 to 9:30 p.m. local time Saturday, during which homes, office towers and landmarks will turn off their lights to raise awareness about climate change. Click on the image to see an Earth Hour slideshow.

Cities around the world are going dark on Saturday night for the annual Earth Hour event, which aims to raise awareness about actions people can take for the environment's sake.

The campaign, now in its fourth year, boasting participation of more than 4,000 cities in 131 countries and territories around the world. Hundreds of millions of people are expected to turn off their lights and other non-essential appliances for an hour beginning at 8:30 p.m. local time.

The symbolic act is expected to darken major landmarks around the world, including the Sydney Opera House in Australia, the Eiffel Tower in Paris and casinos on the Las Vegas Strip.

Beyond 60 minutes
This year organizers are putting an emphasis on actions that go beyond just 60 minutes of sitting around the dark and thinking good thoughts about the planet.

"Earth Hour is a chance for people and communities across the globe to join together with the common purpose of a sustainable future for our planet,” Andy Ridley, co-founder and executive director of Earth Hour, said in a news release. "This year Earth Hour asks people to commit to an action, big or small, for the coming year, taking Earth Hour beyond the hour."

The organizers have set up a special website, Beyond the Hour, for examples of what actions to take and where you can make a pledge of your own. Some ideas:

• Cut down on the use of plastics
• Convert your lawn to a vegetable garden
• Conserve water
• Ride a bike, take the bus, or walk instead of driving

What about human achievement?
If all this sounds like a sacrifice of hard-won creature comforts, you can join up with the Competitive Enterprise Institute's competing campaign, the Human Achievement Hour, which encourages people to leave their lights on "in appreciation for the inventions and innovations that make today the best time to be alive."

To participate, the free-market advocacy group suggests you "gather with friends in the warmth of a heated home, watch television, take a hot shower, drink a beer, call loved on the phone, or listen to music."

Over on GreenBiz.com, this anti-Earth Hour campaign is summed up as the "fight against the fight against climate change" and offers Web links that should let you can watch the rhetorical battle from a ringside seat.

Meanwhile, the Earth Hour organizers have succeeded in getting statements from world leaders on their participation in the event, ranging from U.N. General Secretary Ban Ki-moon to Colombian President Juan Manual Santos to British Prime Minister David Cameron, who said:

"Sharing responsibility holds the key to fighting climate change. It will be the choices we make as individuals which will mean the difference between success and failure. That's what Earth Hour is all about — millions of people coming together to switch off their lights, tackle climate change and protect our natural world."

Will you be one of the millions of people participating this year in Earth Hour? Weigh in with a comment below.

More stories on Earth Hour:

• Must-see slideshow: Earth Hour around the world
• Earth Hour to hit major tourist draws near you
• Million unplug for Earth Hour
• Earth Hour around the world
• Lights out for climate change
• Sydney to San Fran: Lights dim in Earth Hour

Chandra X-ray Observatory

This image comes from a very deep Chandra observation of the Tycho supernova remnant, produced by the explosion of a white dwarf star in our Galaxy. Low-energy X-rays (red) in the image show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave, a shell of extremely energetic electrons.

Scientists have discovered X-ray stripes in the remains of a supernova that may be the first direct evidence that these exploded stars can accelerate particles to energies a hundred times higher than those achieved with the Large Hadron Collider, the most powerful particle accelerator on Earth.

The striking 3-D-esque image of the Tycho supernova remnant was made from a long observation with NASA's Chandra X-ray Observatory. It could explain how some of the extremely energetic particles bombarding the Earth, called cosmic rays, are produced.

Since cosmic rays are composed of charged particles, like protons and electrons, their direction of motion changes when they encounter magnetic fields throughout the galaxy. As a result, the origin of individual cosmic rays detected on Earth cannot be determined, though supernova remnants have long been considered a good candidate for producing the most energetic cosmic rays in our galaxy.

The X-ray stripes observed in Tycho provide support for a theory about how magnetic fields can be dramatically amplified in supernova blast waves, producing cosmic rays. According to this theory, the magnetic fields become a tangled mess and the motions of the particles very turbulent near the expanding shock wave at the edge of the supernova. High energy charged particles can bounce back and forth across the shock wave repeatedly, gaining energy with each crossing.

Theoretical models of the motion of the most energetic particles — which are mostly protons — are predicted to leave a messy network of holes and dense walls corresponding to weak and strong regions of the magnetic field.

Chandra X-ray Observatory

The X-ray stripes are thought to be regions where the turbulence is greater and the magnetic fields more tangled than surrounding areas. Electrons become trapped in these regions and emit X-rays as they spiral around the magnetic field lines.

The X-ray stripes discovered by the Chandra researchers are thought to be regions where the turbulence is greater and the magnetic fields more tangled than surrounding areas, and may be the walls predicted by the theory. Electrons become trapped in these regions and emit X-rays as they spiral around the magnetic field.

That said, the regular and almost periodic pattern of the X-ray stripes (image at right) was not predicted by the theory and caught the researchers by surprise. "It could mean that the theory is incomplete, or that there's something else we don’t' understand," Jack Hughes, a professor of physics and astronomy at Rutgers University, said in a statement.

The size of the holes, or spacing, between the X-ray stripes is thought to correspond to the radius of the spiraling motion of the highest energy protons in the supernova remnant, the researchers say. If so, the spacing corresponds to energies about 100 times higher than reached in the Large Hadron Collider and equal the highest energies of cosmic rays thought to be produced in our galaxy.

The Tycho supernova remnant is named for the famous Danish astronomer Tycho Brahe, who reported observing the supernova in 1572. It is located in the Milky Way, about 13,000 light years from Earth. Because of its proximity and intrinsic brightness, the supernova was so bright that it could be seen during the daytime with the naked eye.

The results were published in the Feb. 20. 2011 issue of the Astrophysical Journal Letters.

More on cosmic rays:

• Leading theory about cosmic rays is shot down
• How deadly are cosmic rays?
• Source of super cosmic rays pinned down
• Galactic cosmic rays hit 50-year high

Virgin

Virgin's Necker Nymph can go to a depth of 130 feet, but the Virgin Group's billionaire founder, Richard Branson, is targeting deeper depths in a new venture.

British billionaire Richard Branson’s Virgin Group is signaling that the time has come for its long-discussed deep-sea exploration and tourism venture.

Advance word comes in the form of an invitation to a Los Angeles press event on April 5, during which a "major new initiative and challenge" will be announced. "The Virgin brand has reached many places — the seven continents of the earth, up into the jet stream and soon, even into space. There is only one frontier left," the Virgin Group's invitation reads.

It doesn't take much sleuthing to figure out the general topic. For one thing, once you rule out Earth's land mass, the atmosphere and outer space, the oceans are the only things left. Also, Branson has been talking about a venture called "Virgin Oceanic" (or "Virgin Aquatic") for a couple of years now.

Branson unveiled one part of his underwater ambitions last year, in the form of the "Necker Nymph." That's a a prototype submersible vehicle that's part of a $113,000 weeklong tour package available on Necker Island, the billionaire's vacation spot in the British Virgin Islands. (It's $25,000 for the sub ride, but another $88,000 for the resort stay). The craft was reportedly built at a cost of $670,000 (£415,000).

But that's just the beginning: When Branson discussed Virgin Oceanic with Time back in 2009, he said the venture would send pressurized submarines to depths of 35,000 feet:

"The oceans need exploring — we know nothing about what's going on under 25,000 feet. I have an island called Necker Island, and 15 miles from there is the deepest place in the whole of the Atlantic, the Puerto Rican Trench. It's quite likely that we'll set up a scientific and exploration center on Necker to send out expeditions to explore that trench and other trenches in the world."

Branson also discussed the idea in a WatchMojo video recorded at McGill University. "Besides discovering new species, charting the trenches and finding treasure, we may even find the lost city of Atlantis," he said.

A few other hints worth noting: VirginOceanic.com has been registered by the Virgin folks and is currently password-protected. AlwaysOn, an agency that has done design work for Virgin in the past, has created a Virgin Oceanic logo as well as some visual concepts for a deep-diving submarine. And Virgin's invitation promises that "eminent scientists" will be in on the L.A. press conference next month.

One eminent scientist, University of Washington oceanographer John Delaney, says he's not familiar with Branson or Virgin Oceanic. But he's in favor of any venture that will increase the public's awareness of the oceans as the world's most complex and crucial set of ecosystems. "The real intellectual power, the real emotional power, is in the recognition that we depend on something we don't understand," he told me today.

Delaney has been working for years on a different approach to marine exploration, based on the convergence of telepresence technologies. Just last month, a construction team began the first installation phase of the Ocean Observatories Initiative's Regional Scale Nodes, a network of fiber-optic cables that could eventually send terabytes of data from high-resolution cameras and other sensors under the sea.

"We can only take hundreds of people to the deep ocean, but we can bring the ocean to billions of people," he said.

Delaney has been in deep-sea submersibles plenty of times, and says it's a fantastic experience. But he hopes Virgin Oceanic can add enough scientific and educational context to turn deep-sea observation into a paradigm-shifting phenomenon. "My fantasy isn't to go to these places physically — but to occupy, in a telepresence fashion, entire volumes of this planetary life support system," he said.

Stay tuned in the days ahead for more about Branson's latest adventure, and about Earth's deep-sea frontier.

More on scientific frontiers:

• Scientists buy suborbital space trips
• Space tourism poised to blast off in two years
• Submersible robots explore the ocean's depths
• Scientists finish their first census of the sea

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto."

Jill Anderson

Researchers put a radio tag on a characid fish in the Amazon. The fish disperse seeds up to 5 kilometers from where they eat fruit dropped by trees and other plants.

The Amazon's big fish poop seeds far from where they eat fruit, helping to maintain the genetic diversity of the tropical forest, according to new research that shines light on a little-studied mechanism of seed dispersal.

The seed excretions occur during the six- to eight-month-long flood season, when the characid fish Colossoma macropomum swim from lakes and rivers into vast floodplains where they gobble up fruit dropped by trees and shrubs.

They poop out the seeds up to 3 miles (5 kilometers) away in the floodplain where they are likely to germinate, according to Jill Anderson, an evolutionary ecologist at Duke University who led the research.

"That's an important point, because if these fish go into floodplain forests for short feeding bouts and then return to the main river channel they could be depositing seeds in rivers or lakes, permanent bodies of water, and then those seeds would die," she told me today.

Study mechanics
To make the finding, Anderson and colleagues radio tracked 24 fish for three seasons at Peru's Pacaya-Samiria National Reserve. The results showed that the fish roam as much as 3.7 miles (5.9 kilometers), spending up to 90 percent of their time in the flooded forests.

The team combined this data with information on how long captive fish retained seeds in their guts before they were excreted.

"Every hour we would collect the seeds they had defecated and so we would know what proportion of seeds they defecate at certain time intervals," Anderson explained to me today. "When you combine that data with data on how the fish are moving, you can model how the seed is moving around the landscape."

They modeled a mean dispersal distance of 1,100 to 1,800 feet (337 to 552 meters), and a maximum of 3.4 miles (5.5 kilometers), though Anderson thinks this is conservative.

Colossoma macropomum can reach a weight of 66 pounds (30 kilograms) but the fish in her study were in the range of a couple of kilograms. "So I'm pretty sure our model is an underestimate of how really big fish would be moving seeds around," she said.

Fish in trouble
The findings may add pressure on efforts to conserve these fish, which have been swimming in the Amazon for 15 million years.

"Because they are so large and they are also tasty, they are really important in human consumption throughout tropical South America," Anderson noted.

In some parts of the fish's range, the population size has declined by up to 90 percent, she added. What's more, the fish that remain are smaller since the big fish fetch a higher price at market.

"We have data showing that these smaller fish are not as good as the big fish at dispersal," Anderson said. "The smaller fish eat fewer seeds, they disperse fewer seeds and they don't bring seeds as far. Basically, overfishing is removing the best seed dispersers from the system."

What this means for the tropical forest is unknown. The researchers have yet to determine how important fish seed dispersal is compared to other dispersers such as monkeys and birds. "That's a question I would like to pursue," Anderson said.

The current findings were published Wednesday in the Proceedings of the Royal Society B.

More stories on seed dispersal:

• Disappearing bird species take plants down with them
• Secret found to flight of 'helicopter seeds'
• Savvy squirrels outwit trees

Juan Cisneros

An illustration by Brazilian paleontologist Juan Carlos Cisneros depicts the mammal-like creature known as Tiarajudens eccentricus displaying its teeth to scare off a carnivorous dinocephalian.

Back in 260 million B.C., the mammal-like creature known as Tiarajudens eccentricus looked as fearsome as any predator —possessing rows of teeth that went all the way back into its palate, with two saber teeth sticking out in the front. But paleontologists say this dog-sized monster lived on a strictly vegetarian diet. So why did it have all those menacing choppers?

In this week's issue of the journal Science, researchers from Brazil and South Africa examine the strange case of Tiarajudens, a newly identified type of distant mammalian relative known as a therapsid, and they go on to suggest possible solutions to the dental dilemma.

First, about those saber teeth: Although they weren't used for spearing prey, they could have been brandished to keep predators away. Or perhaps the teeth helped chop up the Paleozoic salad fixings before Tiarajudens chewed it up.

Juan Cisneros

A reconstruction shows the head of Tiarajudens eccentricus.

Another possibility is that the teeth were actually used by one male against another in the competition for mates. The researchers noted that musk deer use their own saber teeth for just that purpose. Other types of Paleozoic animals, such as dinocephalians, apparently butted heads to fight over mates. Tiarajudens' teeth may have enabled an alternate form of ritualized combat.

"Some other Paleozoic animals also had enlarged canines, but they were all carnivores. This is the first case of a saber-toothed herbivore at that time," research team leader Juan Carlos Cisneros, a paleontologist at Brazil's Federal University of Piaui, told me in an email. "Other herbivores with long canines appeared much later in the Cenozoic, including fossil deer. ... Some researchers have proposed that these fossil deer (which did not possess antlers) used their canines for male-male combat, like modern saber-toothed deer do."

Cisneros said he and his colleagues from the Federal University of Rio Grande do Sul found the Tiarajudens skull in March 2009  during a field campaign in southern Brazil. During the two years that followed, the research team cleaned the fossilized pieces, glued them together and analyzed how they were put together. The creature's name comes from "Tiaraju," the place in Brazil where the fossil was found; "dens," the Latin word for teeth; and "eccentricus" ... well, you can figure that one out yourself.

In addition to the saber teeth, the bunches of teeth in the palate make Tiarajudens eccentricus "extremely unusual," Cisneros told me.

"I would compare it with modern mammals, which have one row of enlarged teeth for mastication — except that no mammal has teeth in the palate, but the animal is so bizarre that no comparison is perfect!" he said.

Why so many teeth? "Tiarajudens, as far as we know, was the earliest therapsid capable of actual chewing," Cisneros said. "Its teeth are an answer to make possible the digestion of abundant but poorly nutritious food (fiber plants)."

Those molars in the palate provided extra chewing power, plus replacements as the teeth wore down.

Present-day ruminants, such as cows and sheep, also have to do a lot of chewing to digest their similarly high-cellulose fare. In fact, they've developed a complex set of stomach compartments to break down their food for multiple chewings. There's no sign that Tiarajudens had a similar digestive system, however.

Did Tiarajudens pass down any of its dazzling dentition to present-day species? Almost certainly not. "They are dead ends," Cisneros said. But the saber teeth and long rows of molars show how some of the same solutions arise over and over again in the course of evolution.

Juan Cisneros

A fossil from southern Brazil shows the skull of Tiarajudens eccentricus, including the remains of its saber teeth and palatal teeth.

"Both the saber teeth and the enlarged molar-like teeth in the palate represent convergence with other similar animals," Cisneros said. "These traits appeared and disappeared many times in therapsids."

The discovery by Cisneros and his colleagues "provides novel insights into early tooth differentiation" among therapsids, as well as the evolution of plant-eating "and its accompanying complex social interactions," Jörg Fröbisch, a paleontologist at the Humboldt Museum in Berlin, wrote in a Science commentary.

Therapsids have often been called "mammal-like reptiles," but Fröbisch told me that term isn't quite correct. "These animals are more closely related to mammals than to reptiles," he said. So maybe we have more in common with the toothsome Tiarajudens than we might think.

In addition to Cisneros, the authors of "Dental Occlusion in a 260-Million-Year-Old Therapsid With Saber Canines From the Permian of Brazil" include Fernando Abdala, Bruce S. Rubidge, Paula Camboim Dentzien-Dias and Ana de Oliveira Bueno.

Join the Cosmic Log community by clicking the "like" button on our Facebook page or by following msnbc.com science editor Alan Boyle as b0yle on Twitter. To learn more about Alan Boyle's book on Pluto and the search for planets, check out the website for "The Case for Pluto."

C. Carr

This 1 inch by 1 inch microfluidic chip is part of the SETG instrument prototype. Tiny channels feed in the samples to be analyzed and control the fluidic circuitry on the chip. Blue light excites fluorescent dyes that help identify DNA within 3072 cubic chambers, each about the width of a human hair, or one billionth of a liter in size.

Life as we know it has a common ancestor — somewhere. Is it a Martian? A new device under development to fly on a future mission to Mars to find and sequence bits of genetic material could provide an answer, according to MIT and Harvard scientists.

"Given what we know about meteorite impacts and transfer of material between Earth and Mars, we are hoping that life may in fact exist on Mars and that it may in fact be related to us," Christopher Carr, a MIT research scientist who is leading the project, told me today.

The idea that life originated on Mars goes back before the Viking missions of the 1970s, which looked for signs of life on the Red Planet. It got a boost in the 1990s with the discovery that microbes could have hitched interplanetary rides on meteorites between the two planets during an intense period of bombardment between about 3.5 and 4 billion years ago.

"About a billion tons of rock probably went between Earth and Mars, most of that actually went in the Mars-to-Earth direction — about a 100-fold higher amount," Carr noted. "So that makes it more likely that if we find something on Mars that's related to us that it actually came from Mars to Earth."

Device development
Carr and colleagues have identified regions of genome sequences that are conserved across all known life forms on Earth and are working on a device that will look for bits of this genetic material on Mars.

The device, called the Search for Extra-Terrestrial Genome (SETG), will isolate any RNA or DNA from bits of soil, rock and ice brought up from the subsurface of Mars, amplify it to the point it could be detected and then sequence it.

So far their prototype consists of the micro-fluidic chip in the image above which can amplify and detect bits of genetic material. In the next few years, they aim to add components to isolate the genetic material and sequence it as well.

"Our hope is that in the next two years, we will have a system that we can put in soil at the beginning and get sequences out at the end," he said. The aim is for an instrument that weighs about 2 kilograms and is roughly the size of a shoebox.

Finding genetic material on Mars that shows a link with life on Earth would allow scientists to learn more about how we are related and when the split occurred. As for whether the scientists will have any luck finding genetic material that shows we're all Martians remains an open question.

"I think it is entirely possible," Carr said. "I wouldn't necessarily say probable. Bottom line, if it is there, we want to find it. It may or may not be."

More stories about life on Mars:

• Did probes find Martian life … or kill it off?
• Were life's building blocks picked up on Mars decades ago?
• Next up for Mars missions: the search for life
• Early cave bacteria hints at Mars life

Greg Woloschyn / Food-bot

The Food-bot website helps hungry college students find campus events offering free food.

For hungry, cash-strapped college students, few things are better than free food. At least that's the reasoning behind Food-bot, an award-winning website that identifies events offering free food on college campuses.

Of course, free food is often just an enticement to get people to events. So, along with food ratings, the Food-bot scales the awkwardness of showing up unannounced and includes estimates of how much time must be invested to get fed.

The website is the brainchild of Greg Woloschyn, who earned a bachelor's degree in computer science from Carnegie Mellon University in 2010. It is this year's winner of the university's Smiley Award*, which is given to students for innovations in technology-assisted person-to-person communication.

(*Carnegie Mellon lays claim to creating the now-ubiquitous smiley emoticon, :-), in 1982.)

Food-bot began as a Gmail account: Woloschyn subscribed to thousands of mailing lists and used a Gmail filter to delete any mail that didn't contain a food-related word. He improved it after learning a few tricks in a course on artificial intelligence.

The program analyzes emails to detect mentions of free food and extracts information on when, where, and circumstances of the feast. The website also allows student groups to post information manually, which in turn helps them publicize their event.

For those who are afraid the Food-bot is further evidence that computers and robots will take over the world, Woloschyn dedicates a section of his website to examples of when Food-bot failed.

"On the one hand, I love to see my program working as expected. But on the other hand, it can be pretty humorous sometimes to see some of the mistakes food-bot makes," he writes.

For example, hungry Berkeley students eyeing a salmon lunch last month with middling time commitment and awkwardness ratings were likely disappointed to show up at a lecture on the "nutrient food-web ecology of Pacific juvenile salmon in freshwater and marine ecosystems under variable anthropogenic and climate conditions."

No doubt visiting professor Asit Mazumder's research is important to fisheries management, but free salmon for hungry students was probably far from his mind that day.

John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).