Illustrated London News

Starving people searching for potatoes in a stubble field during the Great Famine (1845-1852) which was caused by the failure of the Irish potato crop and British government inaction.

Scientists have finally figured out exactly what strain of potato blight led to the deaths of more than a million people in Ireland during the Great Famine of the mid-19th century — and it's not the usual suspect.

For decades, researchers assumed that a particular strain of Phytophthora infestans, known as US-1, made the leap from the Americas to mainland Europe, and then to Ireland in the 1840s. Selective breeding and fungicides have made US-1 less of a threat than it was a century and a half ago, but it and other strains of blight continue to pose a threat to potato crops around the world. Blight can still turn seemingly healthy potatoes into black, stinking balls of mush, just as it did in 19th-century Ireland.

An international team of scientists took on the task of tracing the roots of late blight through genetics, and to flesh out the story, they deciphered the genomes for 11 strains of blight preserved in Germany's Bavarian State Collection for Botany and London's Kew Gardens. The dried potato plants containing the blight pathogens were saved in herbaria — that is, collections of preserved plants — by 19th-century scientists who had no idea they could yield that kind of scientific data.

What the researchers found surprised them: The genetic signature of the blight that was extracted from the Irish potato plants did not match up exactly with US-1. Instead, the blight represented a closely related but previously unknown strain that has now been designated HERB-1.

The study of blight evolution is to be published in the open-access journal eLife.

Roots of the blight
By mapping the genetic differences between the 19th-century samples and 15 modern-day strains of blight, the scientists could reconstruct the pathogen's evolution over the centuries. They determined that the blight originated in Mexico's Toluca Valley. The species' genetic diversity increased markedly in the 16th century, around the time that Spanish explorers settled the New World. That era marked the wider spread of potato varieties, and probably hastened the evolution of Phytophthora infestans as well.

Kew Gardens

This potato specimen from the Kew Gardens' herbarium was collected in 1847, during the height of the Irish famine. The legend reads "Botrytis infestans" because it was not known yet that Phytophthora does not belong to the mildew-causing Botrytis fungi.

The similarities between US-1 and HERB-1 suggest that they both made their appearance in the early 19th century, not long before the first major outbreak of the blight in Europe. "Probably they both came out of the United States," said one of the study's authors, Sophien Kamoun, a researcher at the Sainsbury Laboratory in Britain.

HERB-1 spread to Europe first, and soon made its way to Ireland, where potatoes were the staple crop for millions of poor farmers. "The potatoes at the time were very susceptible to blight," Kamoun told NBC News. More than a million people died between 1845 and 1852, and at least that many emigrated to friendlier locales. Even today, Ireland's population level has not returned to the pre-famine high of 8 million.

US-1's rise came in the 20th century, after the introduction of new potato varieties that were resistant to HERB-1. Eventually, US-1 became the dominant blight strain, and HERB-1 faded away. "We think HERB-1 is most likely extinct," Kamoun said.

Delving into DNA
The research illustrates how useful herbaria can be for resolving decades-old questions about centuries-old plants. "The degree of DNA preservation in the herbarium samples really surprised us," Johannes Krause of the University of Tübingen said in a news release about the study. It also illustrates how quickly evolution can produce new strains of pathogens, Kamoun said.

"The molecular clock turned out to be shorter than perhaps we expected," he said.

The study's lead author, Kentaro Yoshida of the Sainsbury Lab, said the study suggests that crop breeding methods play a role in the molecular evolution of pathogens.

"Perhaps this strain became extinct when the first resistant potato varieties were bred at the beginning of the 20th century," Yoshida said. "What is for certain is that these findings will greatly help us to understand the dynamics of emerging pathogens."

More about plant problems:

• How blight becomes a killer
• Fungal threats become growing concern
• Wind may spread diseases faster than thought

Alan Boyle is NBCNews.com's science editor, and the great-grandson of Michael Boyle, who migrated from Ireland to America at the height of the Irish potato famine in 1847.

Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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

Astronauts aboard the International Space Station photographed this striking view of Pavlof Volcano on May 18. The oblique perspective from the ISS reveals the three dimensional structure of the ash plume, which is often obscured by the top-down view of most remote sensing satellites.

Astronauts aboard the International Space Station captured this stunning view of an ash plume streaming from Pavlof Volcano on May 18.  The volcano began erupting 10 days ago in Alaska's chain of Aleutian Islands, about 625 miles (1,000 kilometers) southwest of Anchorage.

LiveScience reports that "the volcano's ash cloud has reached as high as 22,000 feet" — which is still at least 200 miles (320 kilometers) below the space station. Feast your eyes on additional orbital views of the volcano from NASA's Earth Observatory and the Gateway to Astronaut Photography of Earth. And if you think Pavlof looks impressive from outer space, check out the amazing perspectives from the Alaska Volcano Observatory.

Hordes of winged cicadas are coming out and turning up the music for their biggest party in 17 years, stretching from North Carolina through Virginia to New York — but experts aren't yet sure just how big the party will get.

Billions of the bugs are climbing out from the ground as the spring weather warms up and soil temperatures reach the magic turning point of 64 degrees Fahrenheit (18 degrees Celsius). The warm-up has just reached the proper level in the Northern Virginia suburbs of Washington, D.C., according to Sutron's closely watched temperature tracker.

That assessment is confirmed by on-the-ground eyewitness reports registered on Magicicada.org and Radiolab's Cicada Tracker. John Cooley, an expert on cicadas at the University of Connecticut, took in the full cicada buzz this week during a field trip to Lynchburg, Va. "We've had some good, rip-roaring choruses," he told NBC News.

These Brood II cicadas spend most of their 17-year life cycle underground, patiently nourishing themselves on fluids from plant roots, and then arise for a frantic weeks-long cycle of crawling, flying, mating, egg-laying and dying. When the mating party really gets going, the thrum of the cicadas' call can get as loud as 90 decibels.

"It'll be as loud as a rock concert," University of Maryland entomologist Michael Raupp told NBC News, "but hey, these are teenagers. they've been underground for 17 years. They're going to get in trees, they're going to sing."

Throngs of the inch-long insects have been sighted as far north as New Jersey and New York's Staten Island — and eventually, the wave will make its way up to Cooley's neck of the woods in Connecticut. But for now, the prime territory for the party is still in Virginia, and not so much in New York.

"It's really not quite the real thing up there, but it's starting," Cooley said.

Scientists believe that periodical cicadas (sometimes erroneously labeled as "locusts") took up their pattern of long-term dormancy, followed by a brief blast of above-ground mayhem, as an evolutionary survival strategy. The masses of bugs can overwhelm their predators with sheer numbers, ensuring that they can lay enough eggs for the next generation before they end up as a crunchy carpet underfoot.

The big question for Cooley and other entomologists is whether environmental changes over the past 17 years — ranging from climate change to ground pollution and urban sprawl — will affect the breadth and scale of this year's emergence. "We're interested in those situations where these emergencies are not as extensive or as dense as they were 17 years ago," Cooley said.

Regardless of how big it gets, this party won't get too out of hand — if you're willing to endure the noise and the bother. Cicadas are mostly harmless to humans and other species. And in fact, they can be rather tasty. The cooked bugs have been compared to shrimp, or asparagus, or popcorn, or even peanut butter, depending on how they're prepared. The Washington Post's Kevin Ambrose recently conducted his own gastronomical experiment, and concluded that cicadas taste mostly like small tidbits of "mushy, squishy asparagus."

"It wasn't bad, but I don't want to try it again," he wrote.

Have you had cicadas? Have you heard cicadas? Feel free to add your own field reports as comments below — and sample these video tributes to the cicadas:

• Time-lapse video shows a cicada hatching
• From Virginia: Sights and sounds of the cicadas
• Cicada-cam and cicada show on Science Channel
• Cicada serenades at World Science Festival
• 'Sicka Cicadas,' a song by Kathy Ashworth

Slideshow: Return of the cicada

Take a closer look at the curious 17-year life of the flying bug as the East Coast prepares for an invasion.

Launch slideshow

Previously, on 'Swarmageddon' watch:

• Buggy hordes sighted in Virginia
• 'Swarmageddon' comes to North Carolina
• Bug-watchers see cicadas on the rise
• Cicada invasion generates early buzz

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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 won't be printing out pizzas on Mars anytime soon, but the space agency is paying out $125,000 to study the use of 3-D printing technology for food preparation in space.

"We will be building the components for a prototype" over the grant's six-month period, David Irwin, principal investigator for the project at Texas-based Systems and Materials Research Consultancy, told NBC News.

The ideas is to use a 3-D printer to turn generic mixes of starch, protein and fat into textured foodie-type elements, and then add flavorings with an inkjet device. The result? Theoretically, you could have a warm slice of crusty-type starch material topped with fake cheese, sauce and pepperoni.

SMRC's Irwin was reluctant to discuss the project in detail, in part because the contract with NASA for a Phase I Small Business Innovation Research grant had not yet been signed. But he was optimistic about the long-term prospect: "We're going to do great things," he said.

NASA spokesman David Steitz said the contract was finally signed on Wednesday. The project is part of the space agency's effort to widen the menu options for future space travelers when they head out to Mars or a near-Earth asteroid. Right now, astronauts are eating mostly pre-packaged, pre-processed, shelf-stable foods. But that won't work for a trip to the Red Planet.

"The current food system is not adequate in nutrition or acceptability through the five-year shelf life required for a mission to Mars, or other long-duration missions," Steitz said in an email.

Steitz stressed that the Phase I study is just one small step in what's likely to be a years-long effort to build a 3-D space food printer. "There's a lot between this and a pizza," he told NBC News.

Hello, 'Star Trek'
3-D printing technology could open the way toward the kinds of food synthesizers you've seen in 45-year-old episodes of "Star Trek." Basic unflavored ingredients could be kept in long-term storage — up to 30 years, according to a report on the project published by Quartz. The 3-D printer could build up different blends of the basics with different textures. Food-specific flavorings could be sprayed onto the components of synthetic food. Thus, the same device could turn out pizzas on one day, and tacos on the next.

"It has some merit as a way to avoid some of the problems that are currently experienced with the limited shelf life of the pre-prepared foods that are used by the astronauts," said Jean Hunter, a space food researcher at Cornell University who isn't involved with the 3-D-printing project. "One of the keys to having a good food system is to have a lot of variety."

SMRC's proposal to NASA says that "the biggest advantage of 3-D printed food technology will be zero waste, which is essential in long-distance space missions."

One small step: a cookie
As an initial experiment, SMRC researcher Anjan Contractor produced a chocolate-covered cookie using a 3-D printer, and Quartz quotes him as saying a 3-D-printed pizza is his next objective. If the project turns out the way Contractor and his colleagues hope, we may be seeing a cornucopia of food printouts on Earth as well as in outer space. SMRC says the technology could offer an alternative to the current ready-to-eat meals served up by the military, and even a solution to the world's future food woes. 

"With the anticipated world population of 12 billion by the end of the century, the current infrastructure of food production and supply will not be able to meet the demand of such a large population," the company says in its NASA proposal. "The conventional technologies can only provide marginal efficiency, which is not enough in keeping food prices at affordable level for the population growth. By exploring and implementing technologies such as 3-D printing, this may avoid food shortage, inflation, starvation, famine and even food wars."

What do you think? Is 3-D printing the technology that will feed us on Mars, and on Earth? Will it become a future fast-food fad? Or will the novelty eventually go stale? Feel free to register your opinion using the informal survey above, or add your comments below.

More about the food frontier:

• Burritobot is a precision tortilla-filling machine
• The wild possibilities of printing food
• NASA builds menu for Mars mission

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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: Astronaut Sally Ride

AFP/Getty Images

See images from the life and career of astronaut Sally Ride, the first American woman to fly in space.

Launch slideshow

The White House and NASA say they will honor America's first woman in space, Sally Ride, by giving her a posthumous Presidential Medal of Freedom and putting her name on the camera she helped get installed on the International Space Station.

Word of the memorials came as NASA celebrated the late astronaut's life and legacy at a national tribute titled "Sally Ride: A Lifetime of Accomplishment, a Champion of Science Literacy," conducted at the John F. Kennedy Center for the Performing Arts in Washington.

Ride, who was trained as a physicist,  became the first American woman to go into space when she was launched on the space shuttle Challenger on June 18, 1983. She made another spaceflight on Challenger in 1984. Two years later, that shuttle and its crew were lost in an explosion shortly after launch, and Ride served as a member of the panel investigating the tragedy.

She left NASA in 1987 and went on to co-found Sally Ride Science, a company focusing on science education for girls. She died last year at the age of 61 after a 17-month struggle with pancreatic cancer.

In a statement on Monday, President Barack Obama announced that Ride would be posthumously awarded the Medal of Freedom, the nation's highest civilian honor, during a White House ceremony later this year.

"We remember Sally Ride not just as a national hero, but as a role model to generations of young women," Obama said. "Sally inspired us to reach for the stars, and she advocated for a greater focus on the science, technology, engineering and math that would help us get there. Sally showed us that there are no limits to what we can achieve, and I look forward to welcoming her family to the White House as we celebrate her life and legacy."

Sally Ride's camera
NASA said a camera aboard the space station would be renamed the Sally Ride EarthKAM in honor of the late astronaut, who initiated the EarthKAM program in 1995. The camera was flown in space during five shuttle missions and was moved to the space station in 2001. The program makes it possible for middle-school students around the world to request pictures of specific locations on Earth. EarthKAM spawned a similar program known as MoonKAM, which was an outreach project flown as part of NASA's Grail mission to the moon.

The space agency also established a Sally Ride internship program to help students from underserved backgrounds pursue research interests at one of NASA's centers. As many as 10 internships will be available in the spring and fall semesters of each school year, NASA said in a news release.

"Sally's impact on our nation and future generations of explorers is immeasurable," NASA Administrator Charles Bolden said. "Godspeed, Sally Ride, and thank you for reminding us to reach higher, break barriers and dream big."

Monday's tribute at the Kennedy Center highlighted Ride's contributions to space exploration and science. The presenters included Sen. Barbara Mikulski, D-Md.; tennis legend Billie Jean King; singer Patti Austin; and journalist Maria Shriver.

"Sally Ride Science is thrilled to be presenting a national tribute to Sally to honor her lifelong commitment to space exploration, but also to improving science education and to supporting science literacy for all students," Tam O'Shaughnessy, Ride's life partner, co-founder and chair of the board of Sally Ride Science, said in NASA's news release.

More about Sally Ride:

• US Navy names research ship after Sally Ride
• Moon impact site serves as Sally Ride memorial
• How Sally Ride handled the sexuality issue

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

National Weather Service

This map shows the track of a tornado on May 3, 1999, in green; and the track of Monday's tornado in red. The similarity of the paths is coincidental, but the larger patterns of storm activity in "Tornado Alley" are due in part to the region's geography.

Do tornadoes follow well-worn tracks? Where do the deadliest twisters hit? Will climate change make such storms worse? Monday's devastating tornado in Oklahoma raises some questions for which scientists have ready answers, and others that could puzzle them for years to come:

Was this tornado a repeat of a famous twister in 1999?

For a time, Monday's storm followed a track that was similar to the path of a tornado with the fastest wind speed ever recorded, 318 mph (512 kilometers per hour), which occurred on May 3, 1999. That twister was one of 74 tornadoes that touched down in Oklahoma and Kansas in less than 21 hours, according to the National Severe Storms Laboratory. The 1999 outbreak of severe weather caused 46 deaths and nearly $1.5 billion in property damage.

The tracks weren't all that similar, however: Monday's tornado took a more southerly route as it moved east. And there's nothing unique about the area's geography to make it a magnet for super-powerful twisters, according to Bob Henson of the National Center for Atmospheric Research in Boulder, Colo.

"If there were geographic features, that would tend to cause multiple tornadoes every few years," the meteorologist and writer told NBC News. "Well, why has this been happening only since 1999?"

The similarity in the tracks of these devastating storms is "a good example for how weather events can be clustered in ways that are striking yet ultimately coincidental," Henson said.

A classic example of this phenomenon, he noted, is Codell, Kan., which was hit by tornadoes on the same day — May 20 — in 1916, 1917, and 1918. The third tornado killed 10 people and destroyed a part of the community. "That's a good illustration of how sometimes things like this can just happen in clusters," he said.

NOAA SPC

The purple streaks on this map from the National Oceanic and Atmospheric Administration's Storm Prediction Center stand for tornado tracks from 1950 to 2011. The dark blotches indicate population densities.

But isn't Tornado Alley more prone to deadly twisters?

On a wider scale, the geography of America's midsection makes it more prone to tornadoes than any other region on Earth. The classic explanation is that the Rocky Mountains tend to impede the eastward flow of moist air, while the Great Plains allow frigid air to stream southward from Canada and meet up with warm, humid air from the Gulf of Mexico. However, the National Weather Service's Storm Prediction Center says this is a "gross oversimplification" for the origin of tornadoes.

Cliff Mass, a weather researcher at the University of Washington, cites an array of factors that include strong vertical instabiliity and a large amount of wind shear during the spring. "It turns out that nearly every geographical and meteorological aspect conducive to severe convection comes together here," Mass wrote in an explanatory blog posting this week.

"Tornado Alley" generally refers to the region centered in Texas, Oklahoma, Kansas and points north, where tornadoes are most frequent — but multiple studies indicate that the deadliest twisters occur to the east, in a region that's come to be known as "Dixie Alley." The reasons for that have to do with geography and demographics as well as meteorology in the southeastern United States: Storms tend to move faster, and they're more likely to strike at night. There are more trees and other obstructions to raise havoc. Population densities are generally higher, and the region has many manufactured homes that lack basements in which to take shelter.

The United States has the highest incidence of tornadoes, with an average of more than 1,000 every year, according to the National Climatic Data Center. But other regions of the world have twisters as well. Canada is No. 2 with about 100 per year, followed by northern Europe, western Asia, Bangladesh, Japan, Australia, New Zealand, China, South Africa and Argentina. Britain has more tornadoes than any other country, relative to its land area. "Fortunately, most UK tornadoes are relatively weak," the data center says.

Why do these tornadoes seem to be hitting all of a sudden?

After a relatively quiet start to the tornado season, tornadoes have been erupting from Texas to Minnesota over the past week. A cold front advancing to the east appears to be to blame. That pocket of cold air ran into warm air from the Gulf, causing the warm air to rise and spawning powerful thunderstorms. "It's kind of like the perfect setup," Jeff Weber, a scientist with the University Corporation for Atmospheric Research, told LiveScience.

The earlier calm was due to the fact that jet stream had been dipping farther south than usual for this time of year. That kept the Gulf's warm, moist air from advancing into Tornado Alley early in the tornado season.

Will climate change make tornadoes worse? More frequent?

"The short answer is, we have no idea," Michael Wehner, a climate researcher at the Lawrence Berkeley National Laboratory, told NBC News. For years, Wehner has been studying the climate models for extreme weather, and he's a lead author for the next report from the Intergovernmental Panel on Climate Change as well as the federal government's latest national assessment on climate change.

One problem is that the observational record for tornadoes has not been uniform over time. "It has a bias to it, because more people are living where tornadoes occur, and more people are out looking for them," Wehner said. That contributes to the perception that tornadoes are happening more frequently than they used to.

The other big problem is that current climate models don't have the resolution that's needed to simulate the localized, violent activity of a tornado. Currently, global models are built up from atmospheric interactions on a scale of 100 kilometers (62 miles). Improvements in computer power could soon bring that down to a scale of 25 kilometers (16 miles). That should make it possible for scientists to simulate the weather phenomena that give rise to tornadoes, but not the tornadoes themselves, Wehner said.

On a larger scale, extreme weather events are expected to become more frequent in a warmer world, Wehner said. "The metric that I like to look at is the daily amount of rain for a storm that happens once every 20 years," he said. "That storm, in a much warmer world, would happen more frequently." For example, if the world follows a "business-as-usual" scenario, he projects that the average temperature would rise 11 degrees Fahrenheit (6 degrees Celsius) by the end of the century, and that a once-in-20-years rainstorm would come around every five to 10 years on average.

That doesn't necessarily mean tornadoes would be more frequent, however. In fact, the current projection calls for wetter spring weather in the northern U.S., and drier weather in the Southwest — with Tornado Alley right in the middle. "There's some evidence that there might not be a change" in the character of a tornado season, Wehner observed.

Wehner may sound a bit apologetic about the lack of clear answers in the short term, but in the long term, he's optimistic. "The reason I'm optimistic that we can get somewhere on this is that supercomputing technology is driving this very hard," he said. "We're just getting into the sweet spot for these kinds of issues, with the largest mainframes that money can buy."

Update for 1:50 p.m. ET May 24: We've revised the explanation of the factors behind Tornado Alley's susceptibility to twisters, so that it includes a more nuanced view from the University of Washington's Cliff Mass. 

More about tornado science:

• Why tornadoes seem as if they're on the rise
• Flash interactive: What causes tornadoes?
• Full coverage of the Oklahoma tornadoes

Alan Boyle is NBCNews.com's science editor. Connect with him by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding him to your Google+ circles.

John Roach is a contributing writer for NBC News. To learn more about him, visit his website. 

This story was originally published on Mon May 20, 2013 8:20 PM EDT

Alan Antczak / DVIDS

A trained Atlantic bottlenose dolphin leaps out of the water during a photo session with the Space and Naval Warfare Systems Center Pacific Marine Mammal Team in San Diego.

The U.S. Navy doesn't yet exactly know how a 130-year-old brass torpedo got to the bottom of the Pacific off the coast of San Diego, but they have a couple of dolphins to thank for rediscovering the rare weapon.

The find was so unexpected that the humans didn't believe the dolphins at first.

The marine mammals have been trained by the Navy's Space and Navy Warfare Systems Center Pacific, or SSC Pacific, to hunt for underwater mines and mark their locations. Divers place mine-shaped objects on the sea bottom, and then they teach the dolphins to find them. "It's all part of training to show the dolphins what they're going to be exposed to when they're on real-world missions," SSC Pacific spokesman Jim Fallin told NBC News on Monday.

During an exercise in March, conducted not far from California's historic Hotel del Coronado, the trainers sent a dolphin down to look for the pre-positioned target objects. The dolphin dove down, came back up — and gave the trainers a signal they didn't expect. "It had found something where we knew something shouldn't be," Fallin said.

The training team dismissed that first signal as a false positive. But when the same team went back to the same place with a different dolphin, the location was flagged again, Fallin said. That's when the trainers started taking the animals seriously.

A piece of naval history
SSC Pacific worked with recovery divers and bomb disposal experts to check out what the dolphins had found. At first, they thought the object was merely an old tail section from an aerial drop mine. They quickly changed their minds.

"It was apparent in the first 15 minutes that this was something that was significant and really old," Christian Harris, operations supervisor for the SSC Pacific Biosciences Division, said in a news release. It turned out to be the tail section from one of the first self-propelled torpedoes developed and used by the U.S. Navy, known as the Howell torpedo.

U.S Navy / SSC Pacific

The fins of a Howell torpedo can be seen preserved in water after the object was recovered with the aid of dolphins.

U.S. Navy

The only other Howell torpedo known to exist today is at the Naval Undersea Museum in Keyport, Wash.

More sections were brought up and submerged in water for preservation. Eventually the torpedo will be flown to the Naval History and Heritage Command at the Washington Navy Yard for more thorough study. "What's missing at this point is the nose, and we're not sure where that is," Fallin said.

The 11-foot-long (3.4-meter-long) torpedo was developed by Lt. Cmdr. John A. Howell between 1870 and 1889. The Navy says it was driven by a 132-pound (60-kilogram) flywheel that was spun up to 10,000 rpm prior to launch. It had a range of 400 yards, a speed of 25 knots, and a warhead filled with 100 pounds of gun cotton.

"It was the first torpedo that could be released into the ocean and follow a track," Harris said. "Considering that it was made before electricity was provided to U.S. households, it was pretty sophisticated for its time."

Howell torpedoes were used on Navy battleships and torpedo boats until 1898, when they were replaced by Whitehead torpedoes. Only 50 of the Howells were ever were built. The only other Howell that exists today is sitting inert in the Naval Undersea Museum in Keyport, Wash.

How did the torpedo get there? Fallin said he "can't add any information other than that it was there," he said.

Day of the dolphins
This isn't the first unexpected object located by the Navy's mine-hunting dolphins: Previously, the mammals have detected sunken items including a submerged car and a lobster trap in a place "where a lobster trap wasn't supposed to be," Fallin said. But the Howell torpedo could well rank as the most significant archaeological find for a finny troop that's trained for war.

The dolphins' finest hour came during the Persian Gulf conflicts, when they spotted underwater hazards and served as sentries for the U.S-led coalition's vessels.

"Dolphins remain the pre-eminent capability for the Navy in counter-mine identification," Fallin said. "There's no technology that the Navy has today that replicates the dolphins' natural ability to identify mines ... although our lab is working on those futuristic technologies. We're designing those technologies around the sonar capabilities that are inherent in dolphins. Unmanned autonomous robots have been proven to be pretty capable at this point in shallow water. The technology holds promise."

It's all in a day's work for the dolphins — and for SSC Pacific, an arm of the Navy's Space and Naval Warfare Systems Command that focuses on command and control, communications, computers, intelligence, surveillance and reconnaissance — a group of technologies known as C4ISR. "We represent the nation's only full-spectrum C4ISR laboratory," Fallin said.

More about dolphins intelligence:

• Dolphins appear to do nonlinear mathematics
• Are dolphins the world's second-smartest animals?
• Dolphins sought to protect against terrorists

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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 / STScI

Mars looms large in a Hubble Space Telescope photo - and in the imaginations of those who have signed up for a one-way trip to the Red Planet. "It's not that I'm trying to get away," says 18-year-old Kayli McArthur, one of tens of thousands of applicants. "It's like I'm trying to strive for something more."

A one-way trip to Mars sounds like something you'd wish on your worst enemy — so why would more than 78,000 people from around the world pay up to $75 for a chance to die on another planet?

"I can say I have an ulterior motive," said David Brin, who has written more than a dozen science-fiction novels — including "The Postman," which was turned into a Kevin Costner movie in 1997. "I'd get a lot of writing done, and it might be memorable."

As a master of hard science fiction, the 62-year-old Brin knows better than most applicants what the first Red Planet settlers would face if they're sent off in 2022, as the Dutch-based Mars One venture has proposed.

The settlers would have to be sealed up in habitats, protected from harsh radiation, supplied with machine-made air and water, and nourished by whatever food can be grown on a cold, barren planet. They'd have to keep their sanity, millions of miles away from their families and Mission Control. Worst of all, they'd have to face the fact that there's no guarantee of ever going back.

Will this scheme actually work? "I give it a low probability of happening," Brin said, "and I don't consider it to be the most responsible thing I've ever seen."

Nevertheless, the venture has an attraction for Brin and tens of thousands of others, The ages of those listed in Mars One's database range from 18 to 71. All those applicants are facing a long road even before the first four-person crew gets off the planet. Mars One is accepting applicants through Aug. 31. The field of applicants would first be whittled down by panels of experts. Then they'd undergo trial by reality TV, followed by years of training.

"This may sound crazy, but it kind of reminds me of 'The Hunger Games,'" said Kayli McArthur, an 18-year-old student who's one of the youngest Mars One applicants. "It's cool that it would be televised, but that's not my whole thing."

On the other end of the age spectrum, 71-year-old psychiatrist Sanford Pomerantz is a little surprised that it's taking this long to get something like Mars One off the ground. "I thought by now we would have colonized Mars," said Pomerantz, who's currently the oldest applicant on Mars One's list.

So what's the appeal of Mars One? It's too early for Brin, McArthur and Pomerantz to give a lot of thought to their adventure on Mars, let alone their death on Mars. Instead, they're focusing on the adventure here on Earth. Here's what's behind their thinking:

Mars One

Click on the image to go to David Brin's Mars One application video.

David Brin: 'My main purpose is the conversation'
Brin sees Mars One as just one of a number of ventures aimed at expanding humanity's frontier, ranging from Virgin Galactic's suborbital space tours to Golden Spike's moon missions. "It's emblematic of the new era that we're about to enter at long last — what I call the barnstorming era," he said.

Like the daring airplane fliers of the 1920s, these 21st-century space barnstormers are willing to take bigger risks in hopes of providing bigger thrills — and eventually, earning bigger payoffs. The Mars One project is "a great way to get the discussion going," Brin said.

"You have to assume that it may not work, and that there will be a statue of you on Mars someday," he said. "I'm aware of the tradeoffs, and I'm willing to explore it further, but largely my main purpose is the conversation. We've got to be talking about how we can be a more exploratory people — a more interesting people, if you like."

Brin doesn't doubt that Mars One will find plenty of qualified (and interesting) people willing to take the risk.

"People who cannot imagine any sane person making that choice simply aren't envisioning the wide range of human diversity," said Brin, who has three children in school. "Consider what I told my family. By the very earliest date that Mars One might launch, I expect to be a spry 75-year-old whose kids are already successfully launched, and who might spend a few years doing something truly remarkable."

Even if it means dying on alien soil? Brin isn't completely sure he'd go that far, but he's willing to bet that others would.

"I think you'll find tens of thousands of people who, under those circumstances, will at least ponder it seriously," Brin said.

Mars One

Click on the image to go to Kayli McArthur's Mars One application video.

Kayli McArthur: 'I'm trying to strive for something more'
McArthur, a freshman at the University of Arizona, is one of more than three dozen 18-year-olds on Mars One's list of applicants. Ever since she applied, she's been hearing that she has her whole life ahead of her, so why would she want to leave it all behind for Mars?

"Being young doesn't make me want to do it any less because I have my whole life ahead of me," she said. "It makes it more exciting. ... I love all my friends, my guy friends, my family. It's not that I'm trying to get away. It's like I'm trying to strive for something more."

She has long dreamed of going into outer space, and she figures that her future degree in materials science would come in handy for creating the first interplanetary settlement. "Going to Mars, there are so many opportunities for that," she said. 

So far, her family hasn't stood in her way. "My family jokes, like, 'Oh, Kayli, have your fun with it,'" she said. If the selection process gets more serious, she suspects she might face more resistance from her parents. But not from her grandfather.

"My grandpa is a retired three-star [general] in the Air Force," she said. "We were talking about it. I get really worked up and excited, and he was talking about it, too, and being realistic about it. He said, 'That would be so cool if you were able to do it.' ... I know my grandpa would totally support me."

Mars One

Click on the image to go to Sanford Pomerantz's Mars One application video.

Sanford Pomerantz: 'Grandpa is going to Mars!'
Pomerantz is old enough to remember when the idea of sending people into outer space seemed as far out as the idea of sending people on a one-way trip to Mars seems now. One of the books that made an impression on him in grade school was Robert Heinlein's "Red Planet: A Colonial Boy on Mars," which was published in 1949.

"I started as a physics major in the university, but then I got accepted into med school and changed directions," he said. At the age of 71, he's still a practicing psychiatrist in Topeka, Kan. But he's also still holding onto that boyhood dream of spaceflight.

"The Mars thing is exciting, because I hope it'll stimulate people to get interested in space. ... And I hope it has the secondary effect of stimulating science education, especially in the U.S.," he said.

Just as McArthur believes that Mars will need a materials scientist, Pomerantz believes the crew will need a psychiatrist. "Psychologically, it's going to be an interesting challenge, but human beings are very adaptable," he said. "It'll be exciting to go to a whole new world. It'll be a major step in human evolution."

If Pomerantz ends up being selected for the first Mars crew, he's likely to become not only the oldest human to head for the Red Planet, but the oldest human to go on any space mission. (The current record-holder is John Glenn, who flew on the shuttle Discovery when he was 77 years old.) For now at least, that prospect doesn't faze Pomerantz's three children and two grandchildren. "The grandchildren are excited," he said. "It's like, 'Grandpa is going to Mars!'"

Pomerantz became a certified scuba diver just two years ago, and he still expects to be in good physical and mental shape for liftoff in 2022. "Remember, age is a state of mind," he said. "Chronologlcally, I may be 71. ... But psychologically and physically, I'm definitely in my 20s. I look in the mirror and say, 'Who's that old guy?'"

More about missions to Mars:

• Inspiration Mars: So crazy it just might work
• Buzz Aldrin envisions US leading way to Mars
• Cosmic Log archive on Mars

David Brin's latest science-fiction novel is "Existence," which is set in the latter part of the 21st century and involves matters way beyond Mars.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

Laurent Silvani

The northern lights shine over La Baie in Quebec at 2 a.m. Saturday, in a picture taken by Laurent Silvani. To see more of Silvani's work, check out his Silvani.ca website and his Facebook page.

A slight solar storm ejected from a powerful sunspot sparked northern lights as far south as Colorado on Friday night — and there should be more to come.

The heightened aurora was sparked by a burst of electrically charged particles thrown off from an active spot on the sun known as Region 1748. That region is the one responsible for four powerful X-class flares that blasted out from the sun this week. Region 1748 is just now turning in our direction, and forecasters at the National Oceanic and Atmospheric Administration's Space Weather Prediction Center say it has the potential to throw some hefty storms our way.

Storms from the sun have the potential to disrupt satellite communications and power grids, and in extreme cases, the radiation risk could force airlines to reroute their intercontinental flights to lower latitudes. But Joe Kunches, a spokesman for the prediction center, said experts now have much better capabilities at their command to reduce the risks. And so far, he said, the active sun has been throwing "softballs" at us — at least compared with bigger flare-ups like the Halloween storms of 2003 or the Bastille Day storm of 2000.

The most noticeable effects of recent solar disruptions have come in the form of enhanced auroral displays. SpaceWeather.com reports that faint glows were recorded Friday night in Colorado as well as Vermont, New York, Michigan, Wisconsin, Iowa and Washington state.

Farther north, the fireworks show was significantly brighter. Astrophotographer Laurent Silvani captured some great images from Quebec's Saguenay region, about 100 miles (160 kilometers) north of Quebec City.

"Following a magnetic storm, the aurora borealis was particularly visible in the sky with its waves and colors. A particularly beautiful sight!" he wrote in an email. "Many people from the Saguenay do not know that there are auroras occasionally here. They are surprised to see my pictures every time."

Check out Silvani's website and Facebook page for more.

For additional views of auroral glories — including, yes, some photos of the southern lights as seen from Antarctica —take a spin through SpaceWeather.com's photo gallery. And who knows? You might be able to catch the show yourself over the next couple of nights. Another geomagnetic storm is expected to sweep over Earth's magnetic field on Sunday, according to the Space Weather Prediction Center.

To find out what can be seen from where, keep an eye on the center's Facebook page as well as its Ovation aurora forecast maps. If you're in the aurora zone, the best time to look is after midnight. The best places are far away from city lights, with clear, crisp skies. Got pictures? Share them with us via NBC News' FirstPerson photo upload page.

While you're waiting for those dark skies, feast your eyes on these beautiful time-lapse aurora videos, plus our slideshow: 

Slideshow: Lights in the sky

Click through stunning images of the auroral displays created by geomagnetic storms.

Launch slideshow

More auroral glories:

• Northern lights dance with a comet
• Spend a night with the lights — in a minute
• Cosmic Log's aurora 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 and the rest of NBCNews.com's science and space coverage, sign up for the Tech & Science newsletter, delivered to your email in-box. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

NASA

An artist's conception shows NASA's Kepler space telescope observing a planetary transit.

NASA is getting plenty of advice — and sympathy — as it assesses whether its Kepler planet-hunting telescope can be revived after the failure of its reaction-control system. The reactions from scientists and engineers range from repair tips to an Audenesque elegy. Here's a sampling:

How to fix Kepler
The reason why the $600 million Kepler spacecraft can no longer search for planetary transits is that two of its four gyroscopic reaction wheels can no longer spin. Mission managers say Kepler needs at least three of those wheels in working order to hold its position still enough to stare at alien stars.

The most recent part to fail is known as reaction wheel 4. The mission's deputy project manager, Charlie Sobeck, told reporters that the Kepler team could try putting some reverse torque on that wheel in hopes of freeing it up.

Two other possibilities were raised by Scott Hubbard, who headed NASA's Ames Research Center during the development of the Kepler mission and is now a consulting professor of aeronautics and astronautics at Stanford University.

One option would be to try turning on reaction wheel 2, which failed last July. "It was putting metal on metal, and the friction was interfering with its operation, so you could see if the lubricant that is in there, having sat quietly, has redistributed itself, and maybe it will work," Hubbard said in a Stanford Q&A.

"The other scheme, and this has never been tried, involves using thrusters and the solar pressure exerted on the solar panels to try and act as a third reaction wheel and provide additional pointing stability," he said. The mission's principal investigator, Ames' Bill Borucki, said on Wednesday the thrusters couldn't hold the spacecraft stable enough for planet-hunting. Nevertheless, it might be one of the options under consideration.

For the time being, Kepler has been put into a holding pattern that should minimize its thruster fuel consumption and give the Kepler team several months to weigh all the options, the costs and the potential scientific benefits.

Going beyond Kepler
Even if the Kepler spacecraft can't be revived, Borucki says that only half of the data collected so far have been fully analyzed. He estimates it'll take another two years or so to complete the analysis.

Meanwhile, NASA has just given the go-ahead its next planet-hunting satellite: the Transiting Exoplanet Survey Satellite, or TESS. That $200 million project would put a telescope array in space in 2017 to perform an all-sky survey, looking for exoplanets in orbit around the nearest and brightest stars. That strategy is markedly different from the one used by Kepler, which stared at a relatively small patch of sky straddling the constellations Cygnus and Vega.

This October, the European Space Agency plans to launch a space probe called Gaia to conduct a census of more than a billion stars in the Milky Way. Gaia could detect thousands of distant planetary systems, and measure their orbits and masses using a technique known as astrometry.

ESA is working on another planet hunter called the Characterizing Exoplanets Satellite, or CHEOPS, which is due for launch in 2017. CHEOPS would conduct high-resolution transit observations of stars that have already been found to host planets. 

The $8.8 billion James Webb Space Telescope, which NASA bills as the successor to the Hubble Space Telescope, could conceivably analyze the atmospheres of alien planets. It's currently due for launch in 2018.

Paying tribute to Kepler
NASA's associate administrator for science, John Grunsfeld, said it's too early to consider Kepler "down and out." But many astronomers fear that Kepler's planet-hunting days are finished.

"I think 'The mission is not over' means 'the mission is over,'" Caltech's Mike Brown said in a Twitter update on Wednesday. "Might be other things it can do. But, kids, I think the mission is over."

Alan Boss, an astrophysicist at the Carnegie Institution for Science who's part of the Kepler team, was similarly downbeat. In an email sent to AAAS MemberCentral, he called this week's setback a "disaster":

"I am afraid that the loss of this second reaction wheel effectively means the partial loss of Kepler's main science goal: determining the frequency of Earth-sized planets orbiting their stars at distances such that liquid water could occur on the planets' surfaces. Kepler has taken an outstandingly impressive four years of data, but we still need another three or so years of outstandingly impressive data to be certain of the frequency of Earth-size planets. Right now we have enough data to make an intelligent extrapolation about what that number is, but that is not the same as actually determining that number. Kepler was planned to do that for us. There is no other mission in sight that can reproduce for us what Kepler was in the process of doing. The upcoming (2017) NASA TESS Mission will help to push the exoplanet field forward, but it is not designed to find Earthlike planets around sunlike stars, like Kepler was."

"This is one of the saddest days in my life. A crippled Kepler may be able to do other things, but it cannot do the one thing it was designed to do."

Another Kepler team member, Geoff Marcy of the University of California at Berkeley, told KQED that he felt dizzy and teary-eyed over the spacecraft's situation. "It’s a loss for our species," he said. "That sounds dramatic, but we pride ourselves as a species of exploration, seeking answers beyond the horizon, answers about our place in the universe. And Kepler was answering those questions."

Marcy went so far as to tweak W.H. Auden's poem "Funeral Blues" to pay tribute to Kepler. Here's the astronomer's elegy to a spacecraft:

Stop all the clocks, cut off the Internet,
Prevent the dog from barking with a juicy bone,
Silence the pianos and with muffled drum
Bring out the coffin, let the mourners come.

Let jet airplanes circle at night overhead
Sky-writing over Cygnus: Kepler is dead.
Put crepe bows round the white necks of doves,
Let the traffic officers wear black cotton gloves.

Kepler was my North, my South, my East and West,
My working week, no weekend rest,
My noon, my midnight, my talks, my song;
I thought Kepler would last forever: I was wrong.

The stars are still wanted now; let's honor every one,
Pack up the moon and dismantle the sun,
Pour away the ocean and sweep up the woods;
For nothing will ever be this good.

With thanks to W.H.Auden.

For a video rendition of "Funeral Blues," check out this clip from "Four Weddings and a Funeral."

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

There's been a groundswell of 17-year cicadas in Virginia and other southern states, as revealed by a fresh wave of photos and eyewitness reports. In some areas, the outbreak has been accompanied by the insects' loud chorus call. And that's music to the ears of University of Connecticut entomologist John Cooley.

"That's where I'm heading," Cooley told NBC News. The weather is still too cool in New England and the New York City area for a full-blown Brood II emergence, so Cooley is planning a field trip to watch the insects rise up in Virginia.

This is the big year for Brood II cicadas, which are expected to emerge from the ground in the billions over an area of the East Coast ranging from North Carolina up to Connecticut. The bugs are hard-wired to spend 17 years underground, feeding on the fluid from plant roots, and then pop up during the appointed spring when the soil temperature reaches 64 degrees Fahrenheit (18 degrees Celsius).

For weeks, bug-watchers have been posting their sightings (and soil temperature readings) to websites such as Cooley's Magicicada.org and RadioLab's Cicada Tracker. Another website maintained by the Sutron weather information network tracks the soil temperature in Washington, D.C. 

When the winged cicadas throng, they can cover trees and buildings — and raise a din as loud as a lawnmower or jet engine (90 decibels). Over the course of four to six weeks in May and June, the bugs mate, lay their eggs and die, setting the 17-year life cycle in motion once again. (Scientists theorize that there are evolutionary advantages to the long, odd-numbered cycle.)

Although the cicadas have been patiently waiting for 17 years, some cicada-watchers up north are getting impatient with the pace of the emergence. Cooley said the relatively slow pace may be due to this spring's cool temperatures. In order to bring the soil up to 64 degrees F, air temperatures have to get significantly higher than that on a consistent basis.

"I want 80s and 90s," he said, "and so do the cicadas."

Dave Ellis / The Free Lance-Star via AP

Brood II cicadas emerge in the Leavells Crossing neighborhood in Spotsylvania, Va., on May 16.

Carol via Twitter.com/oikwtm_

Cicadas throng near a house in Fredericksburg, Va.

Carol via Twitter.com/oikwtm_

A cat looks through a screen door as cicadas swarm outside a house in Fredericksburg, Va.

Slideshow: Return of the cicada

Take a closer look at the curious 17-year life of the flying bug as the East Coast prepares for an invasion.

Launch slideshow

More about the cicada outbreak:

• Cicadas crawling out of the ground in droves
• 'Swarmageddon' comes to North Carolina
• Bug-watchers see cicadas on the rise
• Cicada emergence sparks early buzz

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

LEOzoo.org

Archie the anteater nestles on his mom at the LEO Zoological Conservation Center in Greenwich, Conn.

Is it a case of anteater virgin birth, a hormonal quirk or just some desperate hanky-panky? Whatever it is, Armani the anteater's surprising pregnancy has sparked a debate over what animals are capable of when it comes to sex.

The story unfolded at the LEO Zoological Conservation Center in Greenwich, Conn.: Last month, Armani gave birth to a cute baby pup named Archie. The only problem was, Archie wasn't supposed to exist.

Armani already had given birth last August to a female pup named Alice, fathered by a male anteater at the center named Alf. Anteater dads have been known to kill off their progeny, so Alf was put in a separate pen for several months. Marcella Leone, the nonprofit center's founder and director, said Armani and Alf shouldn't have had the opportunity to conceive little Archie.

"It is our protocol that that should not happen, so it's a mystery," Leone told NBC News.

NBC Connecticut: Birth of anteater has zoo staff puzzled

Leone speculated that the "virgin birth" may have been a bizarre case of delayed implantation, also known as embryonic diapause. Some species are able to hold up hormonally on having their fertilized eggs attach to the uterine wall and start developing, apparently as a stress response. That's known to happen to armadillos, which are in the same scientific superorder (Xenarthra) as anteaters. "It's been presumed that giant anteaters can do this as well," Leone said.

Could that be what happened to Armani?

"Given the paucity of literature, it wouldn't surprise me," said Bruce Murphy, director of the University of Montreal's Reseau Quebecois en Reproduction (Quebec Reproduction Network).

Diapause or desire?
Murphy is no expert on anteaters, but he is an expert on diapause. A paper on the subject that he and his colleagues published in the journal Open Biology is featured this week as an "editor's choice" in the journal Science.

A cross-species study published by a different set of researchers in PLOS ONE suggests that Armani may well have been capable of adjusting the dials on the standard six-month gestation period. "Their conclusion, and I think it's a good one, is that maybe every species has a capacity for diapause, if uterine conditions are appropriate," Murphy told NBC News.

Bob Luckey / Connecticut Post

Marcella Leone, founder and director of the LEO Zoological Conservation Center, watches over Armani and her baby, Archie, clinging to her back, on May 10. For more pictures, check out the Connecticut Post's report.

However, it may not be necessary to turn to diapause, or to a different kind of "virgin birth" known as parthenogenesis, for an explanation. Despite the best efforts of the conservation center's staff, it's conceivable that Armani and Alf found a way to couple through the enclosure's high-tensile fence. They may have even indulged in a brief encounter while they were being moved around.

Just minutes to do the deed
"I have seen anteaters breed many times, but that doesn’t mean I know exactly what is going on in amongst all that hair," Marie Magnuson, a biologist at Washington's Smithsonian National Zoo, told NBC News in an email. "There is some thought that there is no actual penetration, just a lot of rubbing up together. If that is the case, then his sperm are doing all the heavy lifting on the job, and a fence would not be an insurmountable barrier — as long as it is chain-link and not solid."

It wouldn't take long for anteaters to do the deed, Magnuson said.

"If they were together, it was long enough," she said. "When doing a re-introduction between our breeding pair, we had planned on taking it slow and safe. We were going to put them together for five minutes and then separate them. At three minutes they were copulating."

Leone doesn't totally exclude the possibility that Armani and Alf had a furtive fling. "You can imagine what any man will do to get to his woman," she joked. "This is not our plan, but nature is a very strong force."

The way she sees it, the story is about much more than a couple of amorous anteaters.

"The thing to really focus on is that a plant or animal becomes extinct every 20 minutes," Leone said. "So the point is to learn as much as we can about giant anteaters out of the wild, so that we can apply that knowledge in the wild as well. Ultimately, the most important thing is to save those wild places for wildlife."

More about animal sex:

• Love and lust: Lessons from the animal kingdom
• Gallery: 10 peeks at sex in the wild
• Biologists say animal sex is sensationalized

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

You'd think that traveling at warp speed to the planet Nibiru would be the coolest thing in outer space, but for the Hollywood types who made "Star Trek Into Darkness," talking with a real astronaut on the International Space Station was way more awesome.

"I'll just act like this is a perfectly normal thing to be happening," Damon Lindelof, a writer and producer for the just-released movie, told NASA's Chris Cassidy during a Google+ Hangout presented on Thursday by the space agency and Warner Bros. "We are literally tickled pink to be talking to you right now."

The other "Star Trek" actors in on the Hangout — Chris Pine (who plays Captain James Kirk), John Cho (Sulu) and Alice Eve (who gets a healthy dose of screen time as Dr. Carol Marcus) — were just as taken. They laughed and hooted like fanboys when Cassidy let go of his microphone and took an upside-down spin in zero-G.

Pine said he loved the idea of mashing up fictional and real-life spaceflight: "It's great that our worlds can meet at some point in the middle and hopefully inspire people to do good things, and to explore."

The feeling was clearly mutual: Astronaut Mike Fincke, who served as space station commander in 2008-2009, said the "Star Trek" TV shows and movies have long inspired scientists, engineers and spacefliers. "We fall for it every time here at NASA," he said.

Fincke appeared in the final episode of the "Star Trek: Enterprise" TV series, and on Thursday he joked that he'd rather be in Hollywood: "Ever since I was 3 years old, I wanted to be a director and writer, but I failed director-writer school. Then I tried acting, and that didn't work out. So now I go on spacewalks." 

If Lindelof has anything to do with it, Fincke won't be the last astronaut to make the crossover to Hollywood. He promised Cassidy that he'd be welcome to a cameo role in a future "Star Trek" movie. "Maybe you could class up the joint a bit," Lindelof said.

Cassidy said the "Star Trek" crew would be welcome aboard the space station as well. He noted that there were currently a couple of vacancies in the U.S. segment of the station — due to the fact that one batch of crew members has just returned to Earth, and their replacements aren't due for launch until May 28. "We got two open beds," Cassidy joked. "The first two here get 'em."

You can watch the whole 56-minute Hangout while you're waiting for the next showing of "Star Trek Into Darkness," but here are a few of the highlights:

• When asked about last week's ammonia coolant leak at the station, Cassidy said he was surprised to see how quickly mission managers were able to plan a spacewalk to fix it. "It's not like you can rescue Spock from a volcano and push a button. It doesn't happen that way up here," he said. Cassidy said the episode illustrated how useful it is to have "garage-tinkerer" types aboard the station.
• Cassidy said ammonia contamination was one of the three emergency threats that the space station crew had to be prepared to deal with, along with an onboard fire or rapid decompression. That led Lindelof to warn the astronaut about the latest "Star Trek" super-villain. "You should watch out for Benedict Cumberbatch," he said. "He's very threatening, I understand."
• Cassidy said the thing that gets him the most about "Star Trek" and other space movies was the ease with which everyone walked around on spaceships, as if artificial gravity was nothing special. Even though weightlessness has its drawbacks, floating around in zero-G would make the movies much more interesting. "Trust me, it's a pretty cool thing to do this anytime you want," Cassidy said.
• The astronauts talked around a question that asked them to name their favorite "Star Trek" captain, but Fincke said his favorite name for a starship would be Enterprise (natch!). Fellow NASA astronaut Kjell Lindgren went with the Starship Endurance, which pays tribute to the ship for Ernest Shackleton's famous Antarctic ordeal in 1914.
• Life aboard the space station tends to give astronauts the same optimistic view of the future that runs through the "Star Trek" saga, Cassidy said. From space, Earth seems so tranquil and peaceful. "There are no borders down there," Cassidy said. "You can't see a little yellow line painted on the green part."
• One of the questions sent in during the Hangout focused on a more mundane aspect of spaceflight: How do spacewalkers handle a sneeze? Cassidy admitted that could be a problem. "Once the helmet goes on, any schmutz that goes on there is just an impediment to seeing clearly," he said. The solution is to incline your head downward before the sneeze, so that the schmutz is directed below the face plate.

More about 'Star Trek' and spaceflight:

• Astronauts get a sneak peek at film
• Warp speed! It may actually be possible
• Gallery: Reality check for 'Trek' tech

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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

An artist's conception shows NASA's Kepler space telescope observing a planet making a transit across an alien star. (Star and planet not to scale.)

NASA's planet-hunting Kepler space telescope suffered a second failure in its reaction-wheel control system, forcing a suspension of its search for alien planets while the space agency determines whether the four-year mission is truly finished.

"It's certainly not good news," Charles Sobeck, deputy project manager for the $600 million mission at NASA's Ames Research Center, told reporters Wednesday.

But Sobeck and other mission managers emphasized that there was still a chance that the probe could be revived. "I wouldn't call Kepler down and out just yet," said John Grunsfeld, associate administrator for science at NASA Headquarters.

The problem has to do with the reaction wheels that are part of Kepler's fine-pointing system. The space telescope identifies worlds in far-off solar systems by watching for the telltale dips in starlight when the planet's disk passes over its parent sun. But in order to make those observations, Kepler has to hold itself in a precise position with the aid of four gyroscopic reaction wheels. One of the wheels failed last July, but Kepler could still do the job with the other three.

On Sunday, however, the spacecraft put itself into safe mode when it couldn't stay in its proper orbit around the sun, 40 million miles (64 million kilometers) from Earth. When the mission team did its regular check-up with Kepler on Tuesday, they found that a second reaction wheel wasn't working. In a mission update, NASA said the problem was probably caused by "a structural failure of the wheel bearing."

That forced an end to Kepler's planet quest. "We need three wheels in service to give us the pointing precision to make this work," the mission's principal investigator, William Borucki of NASA Ames, told NBC News.

Sobeck said the spacecraft itself could remain stable as long as it had fuel for its thrusters, but the thrusters aren't capable of providing the precise pointing that Borucki and his colleagues need. Over the next several months, members of the Kepler team will assess their technical options, and gauge what kind of science could be accomplished using those options, said Paul Hertz, astrophysics director at NASA Headquarters. 

There's still a chance that the reaction-wheel system could be restored — for example, by trying to spin the wheel backward and forward, just as you might spin the wheels of a car that's stuck in a snowdrift. Sobeck said it might even be possible to revive the wheel that was shut down last July. "When we turn it on, it just might start spinning, we don't know," he said.

But mission managers also acknowledged that Kepler's planet-hunting days may be over. Hertz pointed out that the spacecraft outlasted its 3.5-year primary mission, and was currently into an extended mission costing $20 million a year.

Even if the spacecraft's control system can't be revived, it will still take another couple of years to analyze the trillions of bits of data already collected, Borucki said. The mission has already identified 132 confirmed planets and 2,740 additional candidates yet to be confirmed. Some of those worlds are thought to lie within the habitable zones of their planetary systems.

"The prime reason for the existence of this mission is to determine whether Earths are common or rare in our galaxy," Borucki said. So far, the evidence suggests that there are billions of Earth-size planets in the Milky Way. Scientists have not yet identified an Earth-size planet in an Earthlike orbit around a sunlike star, but Borucki voiced confidence that the crucial evidence was tucked away somewhere in the readings that have already been beamed down from Kepler.

"I am really delighted, frankly, with what we've accomplished," he said.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

UTL Scientific

Readings from a laser-mapping system were combined to produce a 3-D map of the Honduran rain forest, and then the vegetation was virtually lifted up from the scene to reveal the ruins of a circular structure.

A high-tech team of scientists and filmmakers shared pictures of what appears to have been a centuries-old civilization in Honduras, one year after they used laser-mapping technology to identify traces of structures in the thick jungle.

The square-shaped and rounded structures, seen in computerized elevation maps of a rugged rain forest, may have been the last vestiges of pyramids, palaces and houses in a fabled settlement known as "la Ciudad Blanca," or the White City.

Tales of Ciudad Blanca have circulated since at least 1526, when the Spanish conquistador Hernan Cortez told King Charles V about a mysterious province called Xucutaco that "must exceed Mexico in riches and equal it in the great size of the towns, the multitude of people and the government thereof." Many explorers have gone in search of the vanished city, driving deep into some of Honduras' roughest and most inaccessible rain forests. Neither riches nor ruins were found.

Nevertheless, the sagas inspired documentary filmmaker Steve Elkins to mount yet another search, this time using an aerial mapping technology known as light detection and ranging, or lidar.

How lidar works
An airplane equipped with the lidar mapping apparatus can bounce laser light off the terrain below, and then gather millions of the reflected readings. Those readings can be interpreted by high-powered software that can produce 3-D maps with an elevation resolution of less than 4 inches (10 centimeters). Such maps can even be "filtered" to peel back the dense vegetation and see the contours of the land below. Using lidar, archaeologists can conduct land surveys that might have required months or years to do on the ground.

"We use lidar to pinpoint where human structures are by looking for linear shapes and rectangles. Nature doesn't work in straight lines," Colorado State University's Stephen Leisz, a member of UTL Scientific's archaeological team, said in a statement from the American Geophysical Union.

UTL / Colorado State University

The left image shows a map derived from lidar readings of rainforest terrain. The readings associated with vegetation have been removed to create the right image, which shows the outlines of a square structure.

UTL Scientific

This lidar focuses on a formation in Honduras' Mosquitia rain forest known as "Structure B."

Archaeologists once thought the rain forests of Central and South America were too rugged to allow for large, highly organized communities like the one described by Cortez. But over the past decade or so, researchers have found evidence to argue that the forests were once much more highly managed by native populations. The idea that the ancient peoples of the Americas created complex cities and roadways in what are now wild forests no longer seems as radical as it once did. That's what inspired Elkins and his colleagues to go ahead with their search.

An 'easy' discovery
A year ago, the team mapped about 60 square miles (160 square kilometers) of Honduras' Mosquitia rain forest, and sent the data back to University of Houston engineer Bill Carter. Carter, who works with the National Science Foundation's National Center for Airborne Laser Mapping, identified the regular outlines of artificial structures after just a few minutes of analysis.

"It was kind of surprising how easy it was to find them," Carter told The New Yorker.

It took months more to map hundreds of ruins at several sites in the target area. On Wednesday, Elkins and his team shared some their images to fellow researchers during a session at a geophysical science conference in Cancun, Mexico, organized by the AGU. The laser images unveiled this week illustrate how structures could be identified beneath the vegetation, but do not show the settlements in a wider context.

"We can't show the overall place because we'd like to protect the site" from treasure hunters and looters, Elkins explained in the AGU's news release.

He said that the UTL Scientific team plans to explore the structures on the ground later this year. (UTL stands for "Under the Lidar".) Eventually, Elkins and fellow filmmaker Bill Benenson, who is underwriting the expedition, plan to produce a documentary about the latest search for Ciudad Blanca.

More about lost cities:

• How lasers helped spot lost city in Honduras
• Lost city of Atlantis may lie off Spain's coast
• Gallery: Seven tales of cities lost and found

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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: The World at Night 2013

Andreas Max Baeckle

The winners of the 2013 "Earth and Sky" photo contest show off the beauties of the night sky and demonstrate the effects of light pollution.

Launch slideshow

Are the images featured in The World at Night's annual "Earth and Sky" photography contest meant to celebrate the wonders of the night sky, or draw attention to the worries about the night sky? They're meant to do both, says astrophotographer Babak Tafreshi.

For example, consider "Stars Over Salzburg," one of this year's top-rated images. Your first impulse is to marvel at the golden glow of the Austrian city, as seen from an Alpine vantage point high above.

"But then you realize the photographer has moved away from the city to the mountaintops in order to separate himself from the light pollution," Tafreshi, founder of The World at Night, told NBC News in an email. "Inside the yellow light cast by the city, people are no longer able to see this beauty."

That's the tragedy of the modern world, right? Studies suggest that as much as 80 percent of the world's population can no longer see the Milky Way, due to the lights that illuminate our cities and roadways. But it doesn't have to be that way, and the picture of Salzburg proves it. Tafreshi pointed out that the direct, unshielded glow of city lights can be seen even from a mountaintop.

"That shows that the lights are shining upward," he said. "Light pollution is not the lights we need for our modern world. It's the unnecessary, wrong-directed and excessive light that scatters to the sky instead of illuminating the ground. It isn't just an astronomer's problem. It's a major waste of energy, it disrupts ecosystems and has adverse health effects."

The International Dark-Sky Association estimates that $1 billion is spent in the United States every year to generate artificial light that goes to waste. And as other countries become more urbanized, the stars disappear from wider swaths of the world.

"Our images try to show how the night sky is an essential part of our environment, and not just an astronomer's laboratory," Tafreshi said. "They display how the night sky is becoming a forgotten part of nature for many people in urban, light-polluted areas. A major goal for us in TWAN imaging is to reclaim the beauties of the night sky and make people aware of this."

The World at Night isn't just about the dark side of the disappearing sky. The winning photos include views that reveal cosmic glories in all their purity. "A good example in this year's contest is 'Crossed Destiny' by Luc Perrot, from Reunion Island near Madagascar," Tafreshi said. "The stunning view of the Milky Way above the Indian Ocean has no touch of our modern world. The galactic band is merged with the horizon of our planet."

Click through our slideshow of images from this year's "Earth and Sky" contest, and check out The World at Night's website for still more cosmic glories and cautionary tales.

More beauties of the world at night:

• The World at Night 2012: Darkness and light
• Slideshow: The World at Night 2011
• All-time top 10 astronomy pictures
• The Month in Space Pictures: April 2013

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

Dan Brown's "Inferno," the latest thriller from the author of "The Da Vinci Code," is another globe-trotting, world-saving adventure — and a chance for readers to ponder a new set of mathematical and scientific puzzles.

In "The Da Vinci Code," Robert Langdon, the world's best-known fictional symbolologist, follows a trail that highlights a controversial reading of the relationship between Jesus and Mary Magdalene. In "Angels and Demons," an antimatter bomb from Europe's CERN research center plays a key part in the plot. In "The Lost Symbol," Langdon teams up with a researcher in noetic science, which tackles woo-woo subjects like ESP and vibrational energies. All three thrillers are seasoned with a healthy dose of secret codes.

"Inferno," released Tuesday, sticks with the classic recipe: The novel's opening scenes are set in Florence, an Italian city with a history as convoluted as its street map. Dante's Divine Comedy provides literary and artistic allusions — and lots of numerological clues for Langdon.

The Italian poet Dante Alighieri was, if anything, more of a numbers freak than Dan Brown: Who else would write a three-book masterwork consisting entirely of three-line stanzas? Each book is divided into 33 cantos — plus an extra one in Dante's Inferno, to make 100 cantos in all. The verses are riddled with references to threes, sevens, nines and other numbers with mystical meanings.

Doubleday

A portrait of Italian poet Dante Alighieri on Dan Brown's latest thriller, "Inferno," contains a coded message in a series of concentric circles: CATROACCR. What does it mean? Read on.

Numerological puzzles
Numbers and codes have played a part as well in the buildup to Tuesday's release of "Inferno." Even the publication date is a puzzle: Greg Taylor, author of "Inside Dan Brown's Inferno," noticed that if you reverse the American date notation, 5-14-13, you come up with the first five digits of pi (3.1415). Brown's publishers later confirmed that the date was chosen for just that reason.

Other clues are hidden in the book cover. (Minor spoilers ahead, so code junkies may want to skip to the next paragraph.) The letters CATROACCR are printed within nine concentric circles overlaid on a portrait of Dante, for example. Cipher fans figured out that the letters could be decoded to spell "Tesoretto," which may (or may not) refer to a small secret room in Florence's Palazzo Vecchio. The cover of the Italian edition displays a different string of letters, CATROVACER, which readers have interpreted as an anagram for CERCATROVA. "Cerca Trova" is Italian for "Seek [and] find" — a phrase that pops up in the first chapter of "Inferno." The phrase also shows up in a mysterious Florentine painting by Giorgio Vasari, a writer and artist who created a famous portrait of Dante. Circles within circles!

Michael Haag, author of a forthcoming guide titled "Inferno Decoded," says it's not surprising that Brown was so taken with numbers, codes and arcane connections. "Dan Brown was brought up in a highly academic background," he told NBC News. "His father's a mathematician whose books are standard works if you're studying math in the United States."

Scientific puzzlers
Dan Brown's fans will be puzzling over a few new scientific allusions as well. One theme has to do with the possibility of unleashing a devastating plague. Haag said that hearkens back to the "Black Death" that swept over Florence in 1348, a quarter-century after Dante's death. "This brought about total desolation, although some people have argued that the plague was actually a boost to the Renaissance," Haag said. Such people say all that death cleared the way for the prosperity and enlightenment that followed.

That sounds like just the sort of argument you'll hear the bad guys using in "Inferno."

Another theme focuses on transhumanism, a movement that aims to enhance humans through genetics, smart drugs, implants and other technologies. Some see transhumanism as the best hope for our species' survival. Others, like historian Francis Fukuyama, regard the concept as one of the world's most dangerous ideas. And that makes it one of the world's most fitting ideas for a Dan Brown thriller, particularly one that's set in Florence.

"During the Renaissance, what happened in Florence was the birth of humanism, so transhumanism is several stages up from that," Haag noted. "It's a potentially fascist activity, because it could lead to the creation of supermen. Who's going to do it? Are we all going to do it, or just some of us?"

Will Dan Brown's latest page-turner actually get people thinking about the real and serious issues surrounding emerging diseases and the potential for bioterrorism, genetic manipulation, human enhancement and bioethics? That sounds like a cliffhanger to me. Feel free to weigh in with your comments below.

More about Dan Brown:

• Decipher the clue, name a location
• 'Da Vinci Code' turns 10 years old
• Lost symbols found?

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

Canadian astronaut Chris Hadfield finished out his five-month flurry of songs, snapshots and social media from outer space with a real doozy: a rendition of David Bowie’s “Space Oddity” that even Bowie is retweeting.

The music video was months in the making: With Bowie's approval, the song's lyrics were tweaked to reflect Hadfield's return from the International Space Station on Monday aboard a Russian Soyuz craft. "Lock your Soyuz hatch and put your helmet on," Hadfield sings in the video. After showing scenes of Hadfield strumming on his guitar and gazing soulfully out the station's windows, the video winds up with a Soyuz parachuting down to its landing.

Since "Space Oddity" went up on Sunday, it's been viewed on YouTube more than 2.7 million times.

The YouTube hit caps off an orbital tour of duty during which Hadfield sent down thousands of pictures via his Twitter account, performed the first original song recorded on the space station, mixed it up with "Star Trek" icon William Shatner and unveiled Canada's new $5 bill. For the past two months, he was doing all this while serving as the station's first Canadian commander.

"He's brought space back, not just for Canadians but for the world," fellow Canadian astronaut Jeremy Hansen told NBC News.

Dreams of space
Hadfield, 53, began his path to stardom during his childhood on a corn farm in southern Ontario. Watching Neil Armstrong's first steps on the moon in 1969 inspired him to dream of becoming an astronaut when he was 9 years old. He started flying airplanes in his teens, and went on to become a fighter pilot in the Canadian Armed Forces. He's been an astronaut since 1992, and he flew on space shuttle missions in 1995 and 2001.

Last December, he finally got his shot at a long-term stint in space — and he definitely made the most of the experience.

Slideshow: The antics and artistry of astronaut Chris Hadfield

Canadian spaceflier Chris Hadfield has posted incredible pictures of the world from space. He has also explained how to brush your teeth, shave and clip your nails while weightless.

Launch slideshow

Hadfield's 28-year-old son, Evan, told NBC News that his father put in several hours a day snapping pictures and sending tweets, in addition to his usual 10-hour work shift aboard the station. "When he wasn't working directly for space station maintenance, or on one of his science experiments, he was doing something with his time to benefit people down here," Evan Hadfield said.

Evan worked long hours, too, without pay. Over the past five months, he has been managing his father's social-media accounts and taking the lead in getting videos like "Space Oddity" produced. "I work about 16 hours a day, seven days a week," he said. "Last week I worked 19 hours a day. ... I read about 13,000 to 17,000 messages a day, and that's just in the morning."

"Space Oddity" was a special case, in part due to a tangle of international copyright issues. The Hadfields started working with Bowie and his team, as well as NASA and the Canadian Space Agency, even before the astronaut's launch in December. "It was definitely something we wanted to do," Evan said.

Why do it? Chris Hadfield hinted at the reasons in a different farewell-to-space video: "Who'd have thought that five months away from the planet would make you feel closer to people?" he asked. "Not closer because I miss them — just closer because seeing this [experience] this way and being able to share it through all the media that we've used has allowed me to get a direct reflection back immediately from so many people. ... It makes me feel like I'm actually with people more, that we're having a conversation. That this experience is not individual, but it's shared and it's worldwide."

Hansen said all of Hadfield's pictures, videos and tweets could be boiled down to a simple message: "We do live on a spaceship, a spaceship called Earth, and we need to work together to protect it."

The next chapter
So what's next? After Hadfield and his two Soyuz crewmates touch down in Kazakhstan, they'll be whisked away in separate directions: Russian cosmonaut Roman Romanenko will head toward Moscow, while Hadfield and NASA astronaut Tom Marshburn will be flown directly back to NASA's Johnson Space Center in Houston for medical checks, debriefings, rest and recuperation.

"We have a lot in store for these guys over a number of weeks," Hansen said. And that's not counting a single tweet.

It's hard to believe that Hadfield will be out of the social-media spotlight for long. "We've still got a lot of stuff," Evan Hadfield said. There are still lots of photos and videos from his father's spaceflight that have yet to be shared. But not even the Hadfields know how all those visions from outer space will come out, and on what timetable.

"I don't know, and I don't even want to speculate, because what if I'm wrong?" Evan said. "I hope, I really hope that people take Dad's message to heart and continue it past his return."

Update for 12:25 p.m. ET May 14: The "Space Oddity" video viewership is up to nearly the 7 million mark, and Hadfield commented on the YouTube phenomenon shortly after his landing in Kazakhstan. "I'm very happy that ... 7 million are interested. It is very interesting and historic to be in space," Reuters quoted Hadfield as saying.

"It's part of humanity to be in space," Hadfield said in Russian. "What we were feeling, what we were doing there, the music we played, this is a big part of our lives." 

More about Chris Hadfield:

• Astronaut's artistry hits warp speed
• How Canada's top astronaut sees the world
• Cosmic Log archive on Chris Hadfield

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 Mon May 13, 2013 7:49 PM EDT

Slideshow: Art of Science 2013

Mingzhai Sun and Joshua Shaevitz / Princeton

Click through the top images from Princeton University's Art of Science Competition, which features images of artistic merit created during the course of scientific research.

Launch slideshow

Worms are a source of wonder in this year's crop of aesthetically pleasing scientific images, served up by Princeton University's Art of Science Competition.

"C. instagram," one of the contest's top photos, features a wriggling network of C. elegans worms on an agar plate covered with E. coli bacteria. Ewwww, right? But when Princeton molecular biology student Meredith Wright looked at the scene through a microscope, she had a different reaction: Cooool!

"I found the pattern on this plate particularly lovely, and was able to capture it with my cell phone by holding the lens of my phone's camera up to the microscope eyepiece," she wrote. "I've since shared the photo on social networking sites and have had friends who've never been interested in biology ask me more about my work because of this photo."

Researchers don't do what they do to create beautiful pictures, but beauty often arises amid the search for scientific truth. That's what the Art of Science program is going for: Images produced in the course of scientific research that have aesthetic merit as well.

This year's theme was "Connections." Andrew Zwicker, director of science education at the Princeton Plasma Physics Laboratory, said that some of history's most exciting scientific discoveries have come from making connections between different disciplines.

"For example, with physics and biology, everyday there is a new finding showing that the two are connected in the most fascinating and profound way," he said in this year's contest announcement. "In a similar vein, connecting the aesthetics of laboratory images to their scientific importance has transformed how we look at our data and results. With the 2013 Art of Science competition, we are celebrating all manner of connections."

Meredith Wright / Princeton Art of Science Competition

"C. instagram" shows masses of C. elegans worms on an agar plate. The picture was taken with a smartphone camera through a microscope, and shared via Instagram.

The connections between beauty and truth are reflected in this year's three top-rated images. First prize goes to Martin Jucker's visualization of Earth's wind patterns in shades of red and blue. Michael Kosk's photomicrograph of crushed birch wood took second place. And third prize went to a many-branching visualization of online connections for the websites set up by the plasma physics lab and by the Lewis Center for the arts.

"These two embroidery-like figures visually give us an idea of the similarities and differences of a website devoted to science and one devoted to the arts," said the prize-winning webmasters, Paul Csogi and Chris Cane.

The three prize-winners will share $500, divided into shares of $250, $154.51 and $95.49 in accordance with the aesthetically pleasing golden ratio. Another 40 images are included in Princeton's Art of Science 2013 exhibit, which opened on Friday in the atrium of Princeton's Friend Center. The works were chosen from 170 images submitted from 24 different departments across campus.

Click through our slideshow featuring some of the pictures in the exhibit, and then be sure to visit the Art of Science website and the Art of Science Facebook page for much, much more. And don't forget to share. That's precisely what Meredith Wright hopes you'll do with "C. instagram."

"This image represents the simple pleasure of finding something beautiful when you don't expect to," she wrote, "and it shows how easy it is to connect science with new audiences by simply clicking 'share.'"

More artistic science to share:

• Solid science turns into crowd-pleasing art
• Creepy critters and cool close-ups
• How beauty was found in a slimeball

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

People are getting all twitchy about the bugs that are coming out in New York and New Jersey after a 17-year buildup, but when it comes to cicadas, Billy Tesh is seeing the real deal in North Carolina.

"I was so excited," Tesh told NBC News from Greensboro, where he runs a company called Pest Management Systems. "I've never seen so many in one location in my life. They were on almost every blade of grass."

And this is just the start: Billions of the insects are due to come out over the next few weeks, across a swath of the East Coast ranging from North Carolina to Connecticut.

These particular cicadas have been biding their time underground since the Clinton administration, in 1996. For 17 years, they've been sucking up fluid from plant roots and waiting for their biological alarm clock to ring. The bugs emerge in droves when the soil temperature reaches 64 degrees.

Other species of cicadas break out from the ground every year, but scientists suspect that the 17-year cicadas (and their 13-year kin) adopted a longer life cycle as an evolutionary ploy to overwhelm their predators with sheer numbers and surprise. When the time comes, masses of insects burrow out of their underground homes, shake off the shells of their childhood, unfurl their wings and look around for mates.

This spring's group is known as Brood II — which comes between last year's Brood I in Appalachia and next year's Brood III in the Midwest.

Tesh knows all about the broods: The 53-year-old pest-control specialist has been through several invasions by the red-eyed, loud-humming bugs. Even by his standards, this year's group of cicadas is special. He realized that on Thursday morning when he stopped by a farm in Stokes County, which appears to be one of the first places to experience the full force of this spring's "Swarmageddon."

"This particular brood is extremely large," Tesh said. He's expecting the cicadas to take noisy wing in the next day or two. "They're probably singing tonight."

Billy Tesh

A cicada and its shell sit on pest-control specialist Billy Tesh's hand during a visit to a farm in Stokes County, North Carolina.

Billy Tesh

Red-eyed adult cicadas clump together in a tree in North Carolina.

Billy Tesh

Hundreds of cicadas and their shells hang from dewy spears of grass in North Carolina.

Marc Dennis

Cicada nymphs make their way along a path on Staten Island.

Judging by the reports posted on Magicicada.org and Radiolab's Cicada Tracker, lots more cicadas have been emerging over the past week or so. Sightings have been reported not only in North Carolina, but in areas as far north as New Jersey and Staten Island in New York, which are traditional stomping grounds for Brood II. Those sightings are generating lots of buzz, but University of Connecticut cicada researcher John Cooley says the bugs in the New York metro area appear to be early risers forced out of their holes by wet weather.

Cooley checked out the cicadas that were emerging at New Jersey's Cora Hartshorn Arboretum. "There are nymphs there, and there are lots of them, but I don't think they are ready to come out," he told NBC News. He doesn't expect these early arrivals to do well, and he thinks the nymphs spotted on Staten Island will be in a similar fix. The weather in the Northeast just isn't spring-like enough yet for full-scale Swarmageddon.

When Swarmageddon sets in, Easterners won't need to wonder: The bugs will cover the ground when they crawl, blot out the sky when they fly and generate a mating hum as loud as a New York subway train (90 decibels or more). After a weeks-long mating season, the adults will die off, leaving behind shovelfuls of bug bodies. Meanwhile, a new crop of nymphs will hatch out from their eggs and burrow into the dirt to begin the next 17-year cycle.

Tesh says people have nothing to fear from the cicada invasion. The insects may damage some of the plants that they crowd onto, but they also serve to aerate and fertilize the soil. He's already gotten several calls from concerned customers in the Greensboro area — but so far, no one has asked him to bring out the pesticides. Instead, everyone has been taking his advice: "Just let Mother Nature take its course."

Slideshow: Return of the cicada

Take a closer look at the curious 17-year life of the flying bug as the East Coast experiences an invasion.

Launch slideshow

More about Swarmageddon:

• Bug-watchers see cicadas on the rise
• Cicada emergence generates early buzz
• All about cicadas on NBCNews.com

Show us your cicada photos by adding #NBCNewsPics to your tweet or Instagram post, or upload your pictures directly by clicking on this box.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

Satellite imagery can serve as a time machine, revealing dramatic change in just a few seconds — but can you imagine documenting almost three decades' worth of all that change, across most of our planet's land mass? A team of imaging experts, computer scientists and journalists did. Now they've unveiled the result: a global database of zoomable, animated satellite views known as Timelapse.

"We believe this is the most comprehensive picture of our changing planet ever made available to the public," Rebecca Moore, engineering manager for Google Earth Engine and Earth outreach, said Thursday in Google's blog announcement of the Timelapse project.

Moore said the project began in 2009, when Google started working with the U.S. Geological Society to make its archive of Landsat imagery available online. The team sifted through more than 2 million satellite images, adding up to 909 terabytes of data, and selected cloudless, high-quality views for every year since 1984.

Carnegie Mellon University's CREATE Lab smoothed the views into seamless animations, and Time magazine built it all into a presentation that supplements the time-lapse animations with commentaries on climate change, urban growth and the other trends that are transforming the planet.

"I've been chiseling away at this project over the last 11 months, and am in awe of the folks who helped this come together in ways I could never have conceived on my own. Some very bright minds figured out how to make the biggest video frames ever constructed, equivalent to 900,000 HD TVs next to one another," Jonathan Woods, the Time project's executive producer (and a former colleague at msnbc.com), said in an email.

Google Earth is also hosting the Timelapse zoomable map. "Much like the iconic image of Earth from the Apollo 17 mission — which had a profound effect on many of us — this time-lapse map is not only fascinating to explore, but we also hope it can inform the global community's thinking about how we live on our planet and the policies that will guide us in the future," Moore said.

When it comes to telling the story of our changing planet, one time-lapse animation is worth a thousand words. But there's more to tell. Find out more about the trends illustrated in the seven animated images you see here:

Columbia Glacier: Alaska's retreating ice reveals how climate change is changing Earth's surface.

Dubai coastal expansion: New islands are sprouting along Dubai's coastline as part of a $14 billion land reclamation effort, arguably the largest project of its kind.

Irrigation in Saudi Arabia: Agriculture amid the deserts of Arabia? It's a growing concern, thanks to huge irrigation projects that take advantage of underground rivers and lakes. The water won't last, though: Hydrologists estimate that it'll be economical to pump water for only about 50 years. 

Lake Urmia drying up: Iran's great salt lake is not as great as it was, and the reason for that is in dispute. The Iranian government blames climate change and drought, while critics blame the dams that have been built around the lake.

Brazilian Amazon deforestation: Satellite imagery documents the loss of Amazonian forest land in Brazil due to road-building, logging and agricultural clearing.

Las Vegas urban growth: What sprawls in Vegas doesn't stay in Vegas. Landsat pictures reveal how urban development has spread out around Nevada's biggest city over the decades.

Wyoming coal mining: The Black Thunder mine in Wyoming's Powder River Basin ranks as the largest single coal mining complex in the world, according to Arch Coal, its operator. Satellite imagery shows how the mine has spread out over the decades.

More time-lapse videos:

• One World Trade Center rises
• Shuttle Endeavour traverses L.A.
• Time-lapse gallery from Photoblog

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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: Greatest solar eclipse hits

Roger Ressmeyer / Corbis

See stunning images from past solar eclipses going back to the 1920s.

Launch slideshow

If you can't make it to the South Pacific's eclipse zone in time to watch the sun turn into a "ring of fire" on Thursday, you can still get in on the spectacle online.

The annular solar eclipse begins at 6:30 p.m. ET (22:30 GMT) in western Australia. Over the course of several hours, the moon's shadow will sweep across Australia, Papua New Guinea, the Solomon Islands and the Pacific from east to west, fading into the sunset off the coast of South America.

Because of the relative position of moon, sun and Earth, the moon can't cover the sun's disk completely. For observers who are situated within a strip of Earth's surface that measures 100 to 140 miles (171 to 225 kilometers) wide and thousands of miles long, only the outer edge of the sun will remain uncovered. That's what produces the eerie ring of fire.

The sight will be much like what was visible during last May's annular solar eclipse, and the course of the eclipse will be similar to the Pacific path that was taken by the moon's shadow during last November's total solar eclipse.

If you are in the zone for the ring of fire, be careful: Even that slim ring of sunshine packs enough of a punch to burn your eyes, and you'll need to take precautions. Those precautions can take the form of eclipse-viewing glasses or filters, or pinhole-camera rigs that let you view the eclipse indirectly.

Caution should be the watchword as well for those who can observe the eclipse's partial phase from a wide swath of the Pacific, ranging from New Zealand to Indonesia and Hawaii, as shown in the animation below. NASA's Eclipse website provides further details, including precise time schedules for the eclipse in a variety of locales.

If you're entirely outside the eclipse zone, you won't be so sorely tempted to gaze at the sun. Instead, you can enjoy totally safe views of the eclipse online. Click on the links below for a few of the options:

Slooh Space Camera: Slooh's coverage begins at 5:30 p.m. ET, during the partial phase that leads up to annularity. Slooh's team will provide the commentary for live video feeds from Tennant Creek, Cape Melville National Park and Cairns in Australia. The show also will feature occasional shots of the unsullied sun from Arizona's Prescott Observatory. You can use a Web browser or Slooh's iPad app to tune in.

Coca-Cola Space Science Center: The Georgia-based center will provide a live video feed from Australia's Cape York starting at 5 p.m. ET.

Amateur webcams: Australian skywatcher Gerard Lazarus is gearing up to capture live video of the eclipse, and there may be other on-the-fly feeds. Follow the Twitter hashtag #ASE2013 for updates. 

Television Down Under: The eclipse is likely to make news Down Under, and it's worth checking Sky News Australia and 3News in New Zealand for TV coverage.

If you miss it: Check SpaceWeather.com, Space.com and Universe Today for images of the eclipse after it takes place. You'll also want to keep tabs on Geoff Sims (@beyond_beneath) and Colin Legg (@colinleggphoto) on Twitter.

If you catch it: Got pictures? Please feel free to share 'em with us via NBCNews.com's FirstPerson photo upload page, and we'll pass along a selection of eclipse pics.

More about the eclipse:

• All about the 'ring of fire' eclipse
• Australia to see second solar eclipse in six months
• Flash interactive: What causes a solar eclipse?

Tip o' the Log to Michael Zeiler and Amanda Bauer for eclipse tips.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

"Astronaut Abby" is at the controls of a social-media machine that is launching the 15-year-old from Minnesota to Kazakhstan this month for the liftoff of the International Space Station's next crew — and if Facebook and Twitter count for anything, it just might get her to Mars someday.

Abigail Harrison says she's always dreamed of being the first astronaut to set foot on the Red Planet, and she sees her campaign to get involved in space station outreach as one giant leap toward that target. 

She has enlisted one of the crew members, Italian astronaut Luca Parmitano, as her mentor and orbital pen pal. Her Rockethub crowdfunding campaign has passed the $20,000 mark and is shooting for a goal of $35,000 for travel and outreach. As the May 28 date for Parmitano's launch approaches, she's juggling radio interviews, Facebook updates, Twitter thank-you notes, public appearances ... and oh, that's right: high school.

"You can run yourself ragged on a campaign like this," Harrison, a sophomore at South High School in Minneapolis, told NBC News. "Last time I checked, I have seven A's this quarter. It's been harder to keep my grades up. I don't have as much free time to relax."

Somehow, Astronaut Abby manages. It doesn't hurt that her mom is a social-media maven who runs a marketing agency as @SocialNicole. "My mom has been an amazing resource to answer my questions and help me learn things during this campaign that I wouldn't have been able to learn myself," Harrison said. She also has corporate sponsors, graphic designers and public relations types on her side to keep the mission on track. But her key space connection is with Parmitano — and for that, Harrison has her mom and social media to thank.

The teenager has been an avid space fan since she was 6 or so. Two years ago, she and her mother traveled to NASA's Kennedy Space Center to see the final launch of the shuttle Endeavour. @SocialNicole participated in the mission's Tweetup, which gave a select group of Twitter users the opportunity to meet with NASA officials and astronauts, including Parmitano. She had a chat with the Italian, talked up her daughter and said she hoped they'd meet someday.

"Coming back through the airport, my mom and I turn around at security, and Luca was standing right behind us," Abby recalled. That was the beginning of a friendship that resulted in the #SoyuzAdventure outreach project.

"I will mentor you now," Parmitano told her, "and someday I will train you for your mission to Mars."

Harrison will be attending the Soyuz launch at Russia's Baikonur Cosmodrome in Kazakhstan as Parmitano's guest, and she plans to send back dispatches about her travels. During Parmitano's six-month mission on the space station, Astronaut Abby will be checking in on a daily basis as the astronaut's "Earth Liaison." She'll pass along what she finds out via email blasts, blog items, Facebook updates, Twitter tweets and maybe even the occasional Google+ Hangout.

The contributions she's received so far will pay for the trip to Baikonur, and she'll scale her education and outreach efforts to fit her funding.

This may not sound like the traditional path toward an astronaut career, but maybe it's the wave of the future. "It's definitely been a learning process to step away from the idea that being an astronaut is more than just math and science," Harrison said. She still has a passion for science — particularly for biology and geology. And she still has a passion to be among the first to walk on Mars. "I have a saying, 'Mars or Bust, 2030,'" she said. But she also has a passion for social interaction, and she has learned from Parmitano to work that into her career plans as well.

"Do what you love, not what you think NASA is looking for," she quoted her mentor as saying, "because NASA is looking for people who are passionate about what they do."

In 2030, Astronaut Abby will be 32 years old — which is how old Sally Ride was when she became America's first woman in space. That sounds just about right. 

More about students and space:

• NASA to launch student-built radiation shield
• Mars project is a whole new world for kids
• Students help NASA control robots from space

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

Space Warps Collaboration

The green crosshairs pinpoint a gravitational lens lurking in an astronomical image.

Think you can find space warps? Astronomers have recruited thousands of citizen scientists to look for exoplanets, galaxies, moon craters and other cosmic curiosities — and now they need your help to go after one of the weirdest phenomena in space-time: gravitational lenses.

The Space Warps website gives Internet users the opportunity to sift through telescope images and spot galaxies so massive they bend the light rays that pass near them, like a lens. The venture could help crack some of the secrets of dark matter, the mysterious cosmic stuff that is more plentiful than the ordinary matter we see around us.

"Not only do space warps act like lenses, magnifying the distant galaxies behind them, but we can also use the light they distort to weigh them, helping us to figure out how much dark matter they contain and how it’s distributed," Oxford University physicist Phil Marshall, one of the leaders of the Space Warps research team, said in Wednesday's kickoff announcement.  "Gravitational lenses help us to answer all kinds of questions about galaxies, including how many very low-mass stars such as brown dwarfs — which aren’t bright enough to detect directly in many observations — are lurking in distant galaxies."

Space Warps is the latest gem in Zooniverse's constellation of online citizen-science ventures — a constellation that also includes Planet Hunters, Galaxy Zoo, Moon Zoo and much, much more. The warp-hunting effort follows the model set by those other projects: Participants are given online training exercises to sharpen their lens-spotting skills, and then they're set loose to check sky survey images from the Canada-France-Hawaii Telescope.

"Computer algorithms have already scanned the images from the CFHT survey, but there are likely to be many more space warps that the algorithms have missed. Realistic simulated space warps are dropped into some images to train the volunteers how to spot them, and reassure people that they are on the right track,’ said Anupreeta More, project co-leader from Kavli IPMU in Tokyo.

Galaxy Zoo already has demonstrated that human eyes and brains are much better than automated computer software when it comes to recognizing the subtle characteristics of astronomical phenomena. Dozens of scientific papers have been spun off from Galaxy Zoo searches — including reports on the headline-grabbing blob of green gas known as "Hanny's Voorwerp."

Space Warps could well uncover similar curiosities. Warp-hunters will be able to discuss their finds with each other and with experts on the project's online forum, and even create computer models of their discoveries. A list of gravitational lenses will be published for amateurs and professionals to investigate further.  

"Even if individual visitors only spend a few minutes glancing over 40 or so images each, that's really helpful to our research — we only need a handful of people to spot something in an image for us to say that it's worth investigating," said Oxford's Aprajita Verma, another leader of the Space Warps team.

So what are you waiting for?

More about gravitational lenses:

• Cosmic lenses find farthest galaxy yet
• Crazy cosmic lens focuses on dark matter
• Dark energy illuminated by cosmic lens

The Space Warps collaboration currently includes Phil Marshall, Aprajita Verma, Matthias Tecza, Chris Lintott, Rob Simpson (University of Oxford), Anupreeta More, Surhud More (Kavli IPMU), Amit Kapadia, Kelly Borden, David Miller, Arfon Smith (Adler Planetarium), Jean-Paul Kneib (EPFL Lausanne), Rafael Kueng, Prasenjit Saha (University of Zurich), and citizen scientists Elisabeth Baeten, Claude Cornen, Cecile Faure, Thomas Jennings, Stuart Lowe, Christine Macmillan, Julianne Wilcox and Layne Wright. Organizers say it is about to get a lot bigger.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.

Almost a third of America's honeybee colonies bit the dust last winter, according to a bellwether survey of bee health. But the deaths didn't fit the typical pattern for colony collapse disorder, the mysterious malady that wipes out bunches of bees all at once. Instead, researchers suggest that last summer's drought and other common-sense factors were to blame.

The annual survey of beekeepers, conducted by the Bee Informed Partnership and the Apiary Inspectors of America, found that 31.1 percent of the colonies were lost over the winter of 2012-2013. That compares with a loss of 22 percent during the previous winter, which was exceptionally mild. It's also slightly higher than the six-year average of 30.5 percent in colony losses.

The past winter's bee death rate was roughly as high as it was during the winter of 2006-2007 — when colony collapse disorder, or CCD, was at its peak. But this time, most colonies "dwindled away rather than suffering from the sudden onset of CCD," Jeff Pettis, a U.S. Department of Agriculture bee expert who worked on the survey, said in a news release announcing the results.

University of Maryland entomologist Dennis vanEnglesdorp, who directs the Bee Informed Partnership, listed several likely causes for last winter's spike. One prime reason is the drought that swept over the Midwest last year. "When there's a drought, the bees are in poor shape with the food," California beekeeper Randy Oliver told NBC News in March.

Honeybees may have had to rely on irrigated crops rather than wildflowers for their nectar, which could have increased their exposure to pesticides, vanEnglesdorp said. He said last year's rising corn prices led farmers to replace prairie and shrubs with cornfields, further limiting the bees' foraging areas. And for part of the year, beekeepers lacked an effective treatment for Varroa mites, a type of bee parasite that was cited last week as the biggest factor behind the nation's bee die-off.

VanEnglesdorp said all these factors left bee colonies in a weakened state for the tough winter of 2012-2013. He said the beekeepers who took their hives to California in February to pollinate almond trees suffered especially high losses. Nearly 20 percent of those beekeepers said they lost 50 percent or more of their colonies over the winter.

Pettis noted that the survey stopped tracking losses at the end of April. As a result, "the 31 percent figure likely underrepresents the losses, as we saw many weak colonies that were not actually dead," he said.

Beekeepers rebuild their colonies in the spring, so a 31.1 percent loss rate isn't quite as catastrophic as it sounds. Nevertheless, vanEngelsdorp said high winter losses are changing the way commercial beekeeping is done. "All the money you're going to make in honey goes to replacing dead colonies and keeping your colonies alive," he said. "Any money you make [as profit] will be from pollination."

More about the bees:

• Die-off blamed on combination of causes
• EPA steps up pesticide review
• NBC News archive on the bee crisis

The winter colony loss survey was funded by USDA. The 6,287 U.S. beekeepers who responded to the survey managed nearly 600,000 bee colonies at the start of the survey period, or about 23 percent of the country's estimated 2.6 million colonies. A complete analysis of the survey data will be published later this year.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's 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.