NASA mulls asteroid capture mission, eventual manned visits

NASA is working on plans to robotically capture and tow a small asteroid back to Earth's vicinity by the end of the decade, setting the stage for manned visits to learn more about the threat asteroids pose, the resources they represent and to help perfect the technology needed for eventual flights to Mars.

"This is part of what will be a much broader program," Sen. Bill Nelson, D-Fl, said in a statement late Friday. "The plan combines the science of mining an asteroid, along with developing ways to deflect one, along with providing a place to develop ways we can go to Mars."

According to a mission overview obtained by CBS News, the rationale for the proposed asteroid retrieval project is based on NASA's long-range goals of advancing technology development; providing opportunities for international cooperation; developing new industrial capabilities; and helping scientists better understand how to protect Earth if a large asteroid is ever found on a collision course.

The program also would help NASA develop the navigation, rendezvous and deep space operations experience needed for eventual manned flights to the red planet.

"I hope it goes forward," said Rusty Schweickart, a former Apollo astronaut who helped found the B612 Foundation, a non-profit organization dedicated to building and launching a privately funded space telescope to search for threatening asteroids.

"Asteroids are a very, very interesting area," he told CBS News in a telephone interview. "They're a hell of a resource, and I think the potential for long-term resource development for use in space is going to be a very big thing. And this is sort of step one. It's a baby step in a way, but it should be very interesting."

As for the threat asteroids pose to Earth, Schweickart said "I don't want people to spend their nights worrying about getting hit by asteroids. But I do want them to encourage their political leaders to invest in the insurance, which will allow us to prevent it from happening."

Aviation Week & Space Technology magazine first reported the proposed asteroid retrieval mission, saying NASA's fiscal 2014 budget request would include $100 million to get the project underway.

"Suggested last year by the Keck Institute for Space Studies at the California Institute of Technology, the idea has attracted favor at NASA and the White House Office of Science and Technology Policy," Aviation Week reported. "President Obama's goal of sending astronauts to a near-Earth asteroid by 2025 can't be done with foreseeable civil-space spending, the thinking goes.

"But by moving an asteroid to cislunar space -- a high lunar orbit or the second Earth-Moon Lagrangian Point (EML2), above the Moon's far side -- it is conceivable that technically the deadline could be met."

Louis Friedman, former director of the Planetary Society and a co-author of the original Keck study, said the proposed mission "is quite an exciting idea" that supports President Obama's 2010 call for sending astronauts to an asteroid.

"It turns out, a first mission to an asteroid is still a big step, too big a step, because you'd need a much larger launch vehicle than we're building, you'd need a crew support system that could last for at least nine months in space because of the round-trip time," Friedman said in a telephone interview. "If we have to wait for that, it would be a couple of decades.

"But the nice idea here is we can robotically move the asteroid closer to Earth and do the mission as soon as ... the 2020s, the goal is 2025. By moving the asteroid here, we have a much safer, earlier first step for humans going beyond the moon."

The mission has "both technical advantages and scientific advantages because we're actually exploring an object instead of going to empty space," he said. "It also has an excitement about it because we get the robotic mission, which is a very interesting idea, moving an asteroid close to Earth ... and then sending astronauts up to visit it."

The Keck study estimated a cost of about $2.65 billion to capture and return a carbonaceous asteroid roughly 20 feet across. NASA officials had no official comment Friday and the mission outline obtained by CBS News did not include cost estimates.

But the proposed NASA project closely follows the Keck scenario. The outline indicates a three-pronged approach, starting with enhanced efforts to identify suitable targets. The idea is to find a number of near-Earth asteroids roughly 20 to 30 feet in diameter in favorable orbits that would permit capture and transport to Earth's vicinity.

"The only real question when you come right down to it is the size, because obviously as you get smaller and smaller and smaller, it becomes more and more feasible to do it," Schweickart said. "As you get smaller, the biggest problem you have is knowing where the heck to find one. We don't have a lot of seven-meter objects in our database."

But multiple candidates are needed "because any kind of a schedule slip and that asteroid that you were going to go to may not be back for 15 or 20 years," Schweickart said. "So you need to have a whole set of these things."

Along with improving asteroid detection, NASA hopes to start work on developing a robotic spacecraft based on a 30-kilowatt to 50-kilowatt solar-electric propulsion system that could rendezvous with the asteroid, capture it in a bowl-like receptacle and maneuver it back to Earth's vicinity.

A "notional" timeline in the mission overview shows a test flight in the 2017 timeframe followed by a rendezvous and capture mission in 2019. The asteroid then would be hauled back to cislunar space by around 2021.

Asteroids roughly the size of the desired candidate hit Earth's atmosphere on a regular basis and typically break up harmlessly in the atmosphere. For comparison, the meteor that exploded over Russia in February -- the largest known body to strike the Earth in a century -- was roughly 50 feet across.

In any case, the proposed mission outline indicated any effort to move even a small asteroid back to Earth's vicinity would be built around a fail-safe trajectory that would result in a lunar impact, at worse, if anything went wrong.

The third element of the proposed program would utilize NASA's Orion crew capsule and a new heavy-lift booster to ferry astronauts to the asteroid for an up-close examination and sample return.

Two NASA teams currently are studying the proposed mission. One is focusing on identifying suitable asteroids and developing the unmanned systems needed to capture and return a candidate to Earth's vicinity. The other is studying manned rendezvous and sample-return scenarios.

"There is much forward work to do to better characterize the cost, schedule and mission requirements, and focus an observation campaign to find candidate asteroids," according to the mission outline. "The study work will be done in FY 2013. Many key out-year elements are already in the budget."

Friedman said the proposed mission would be reminiscent of the Apollo moon program, "of having humans go to a celestial object and make measurements that are of interest to various scientific communities."

In the wake of the Russian meteor and a larger asteroid that passed close to Earth the same day, Friedman joked, "if you're not interested in asteroids, what are you interested in?"

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Curiosity’s ‘driver team’ will face challenging trip to Martian mountain

Speaking to an audience in Taipei Sunday, Yen Jeng, the only Taiwanese on the “driver team,” talked about what it is like to drive NASA’s $2.5 billion rover.

Referring to himself as a “taxi driver,” Yen told the audience that he and his colleagues spend approximately 10 hours each day preparing for Curiosity’s next move before transmitting their instructions to the rover.

During an interview with The Central News Agency, Yen said that the rover moves an average of 50-60 meters per day. “Its furthest record was 140 meters a day,” Yen told CNA.

Yens also told CNA that the best moment of the Curiosity mission so far was seeing the first photo of the rover’s landing. Yen admitted that taking a photo of the rover was exceedingly difficult.

Given that the rover was traveling at a high speed, Yen said it was “not easy” for the snapshot to be taken.

“It meant that our landing model was accurate, to know its trajectory,” he said. This is just one example of a maneuver that he and his team spent countless hours practicing and perfecting before passing the instructions on to the rover.

Yen’s description of what it is like to drive the rover comes as Curiosity prepares for a rather-busy New Year. According to The Associated Press, Curiosity will set off toward a Martian mountain in 2013. Curiosity’s current schedule shows the rover taking off for Mount Sharp in mid-February.

“We’ll probably be ready to hit the pedal to the metal and give the keys back to the rover drivers,” mission chief scientist John Grotzinger told The AP in a recent interview.

Curiosity’s trip to Mount Sharp will be an important one, as much is expected of the rover. The AP notes that the mountain, which towers three miles above the center of Gale Crater, has some interesting layers of rock that scientists are excited to explore. The rover’s trip to Mount Sharp is all part of NASA’s quest to determine whether Curiosity’s landing site ever had the right environmental conditions to support life.

Yen and his “driver team” will have to be on top of their game when they maneuver Curiosity toward the mountain.

“We’ll need to be pretty careful,” project manager Richard Cook told The AP. “We may find terrain that we’re not comfortable driving in, and we’ll have to spend time driving around stuff.”

Yen told CNA that reaching and exploring Mount Sharp will give scientists a better understanding of Mars’ geological history.

Being a part of the rover’s “driver team” has been an honor, according to Yen.

 According to a NASA press release, Curiosity recently took a self-portrait using its Mars Hand Lens Imager camera. The rover held the MAHLI camera in more than 50 positions in 24 hours to create a single scene combining all the images, putting together a full-color portrait of the rover itself.

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Rover Curiosity gears up to find Martian bedrock

Los Angeles: After being parked at a sand dune for a month, NASA’s over Curiosity is set to move on to find Martian bedrock for drilling into. 

The rover has been scooping up soil and studying the atmosphere. It is three months into a two-year mission to determine whether the environment could be favorable for microbial life. 
Mission deputy scientist Ashwin Vasavada expected Curiosity to be on the move in the "next few days." 

"It's the bedrock which really gives you the story of ancient Mars," said Vasavada of the NASA Jet Propulsion Laboratory, which manages the USD 2.5 billion mission. "The soil is a little harder to interpret because we don't know how old it is or where it came from." 

The car-size rover touched down in Gale Crater, an ancient depression near the Martian equator, in August on a two-year mission to probe whether the landing site once had conditions capable of supporting microbial life. Armed with a high-tech suite of instruments, it's the most sophisticated spacecraft to ever land on the red planet. 

During the first three months, a weather station aboard Curiosity detected brief drops in air pressure, a sign of whirlwinds in the region. 

"These events are starting to occur more and more often," said Manuel de la Torre Juarez of NASA JPL. "We expect to see more in the future." 

Previous rovers have spotted and even recorded dust devils dancing across the Martian terrain, but scientists said Curiosity has not yet seen evidence that the swirling winds have lifted dust. 

Curiosity's ultimate destination is a 3-mile-high (5-kilometer-high) mountain rising from the center of the crater floor that's rich in mineral deposits. Scientists had hoped to drive to the base before the end of the year, but that doesn't look likely after the extended stay at its current spot. 

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Curiosity Mars rover starts 'to eat dirt'

Nasa's Curiosity rover has ingested its first Martian soil sample.

The robot has taken a pinch of dust into the CheMin instrument, one of its two big onboard analytical tools.

It is a key moment for the $2.6bn mission - Curiosity's internal apparatus will play a central role in its investigation of the Red Planet.

"The most important thing about our mobile laboratory is that it eats dirt - that's what we live on," chief scientist John Grotzinger told the BBC.

CheMin provides definitive mineralogy – it uses X-ray diffraction to identify and quantify the minerals present in the rocky material that has been swallowed.

Engineers received confirmation on Thursday that the sample was accepted by the instrument, and details of the analysis may be available as early as next week.

The dust is the lightest and finest material the rover has been able to pick up with its scoop and system of sieves and sorting chambers.

It should provide researchers with the broadest view of what makes up the soil covering the planet’s surface.

The size of the grains – about a tenth of a millimetre in diameter, and smaller – makes them sufficiently tiny to be blown vast distances in the Martian wind.

“These are particles that travel regionally, if not globally,” said Prof Grotzinger, who is affiliated to the California Institute of Technology (Caltech).

“We see these globe-encircling dust storms and we believe that there are grains that are deposited uniformly all over Mars.

“[We're] going to be able to analyse finally, once and for all, the mineral composition of this global component – not of the local component; not of the bits and pieces of the rocks that are around [our landing site], but the stuff that swirls around the planet; and that’s why this is going to be such a cool measurement.”

Curiosity landed on the floor of Gale Crater, a huge depression on Mars' equator, on 6 August (GMT).

Since then, it has rolled more than 480m (1,590ft) to the east to try to get to a location referred to as Glenelg, a place satellite images have indicated is an interesting junction between three different geological terrains.

It is all but upon Glenelg now, but has paused in the drive these past two weeks to practise scooping and sorting soil samples on a patch of ground the rover team has nicknamed Rocknest.

The robot needed to run material through its mechanism several times to scrub any residual Earthy contamination that may have been coating surfaces; and the sand and dust at Rocknest appeared to have the right properties for the job.

On completion of this cleaning process, it became possible to deliver a sample for test in the CheMin (Chemistry & Mineralogy) tool, and subsequently, in the coming days, to the other big lab in Curiosity’s belly – Sam, or the Sample Analysis at Mars instrument.

Sam will look for the presence of organics - carbon-rich molecules that may tell us something about the possibilities for life on the Red Planet both now and in the distant past.

Engineers have been concerned at the number of small pieces of man-made debris they are seeing around the rover. These are likely bits of plastic that have fallen off the vehicle, or were deposited on to it by its landing crane and have since dropped to the ground during the drive.

The team is not worried that these debris items indicate a major breakage on Curiosity; rather, the issue is that the objects could accidentally be picked up in the scoop and be ingested by the laboratories, seriously skewing their analyses.

Engineers commanded the rover to dump one scoop when a bright fleck was seen during the dig.

However, later imaging suggested this item was probably natural Martian material, and the scientists will now hit the 2mm-wide grain with the ChemCam laser spectrometer to probe its properties further and to work out why it appears so much brighter than all the material around it.

Rocknest: A patch of sand and dust just downhill from a cluster of dark rocks has been the first scoop site

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Curiosity Rover Finds Rock Type That’s Never Been Seen on Mars

After shooting it with lasers and X-rays, NASA’s Curiosity rover has determined that a rock nicknamed “Jake Matijevic” is of a variety that no other rover has ever spotted on Mars.

The rock, a highly fractionated alkalic rock type, is relatively well known to geologists since it is common in rift zones on Earth, such as volcanoes of the Hawaiian Islands.

“This is a rock type which had not been seen before” by previous Mars rovers including Spirit and Opportunity, said Roger Weins, principle investigator for Curiosity’s ChemCam instrument, during a NASA press conference Oct. 11. It forms under relatively high pressure and often in the presence of water. While Curiosity is mostly focused on sedimentary rocks that could indicate the presence of past conditions for life, Matijevic is an igneous rock that likely formed about 5 miles under the Martian surface.

The rover had been investigating Matijevic mostly as an early test of the instruments on its arm, such as the Alpha Particle X-Ray Spectrometer (APXS), which bombards a sample with X-rays to determine its chemical composition. Curiosity also used its ChemCam instrument to shoot the rock with more than 400 laser blasts, vaporizing microscopic amounts and then analyzing the resulting dust and plasma. This investigation showed that the rock contained a lot of elements such as silicon, aluminium, sodium, and potassium.

“This was surprising because it differed from the composition from what we know of rocks on Mars,” said Edward Stolper, Curiosity science team co-investigator, during the conference.

Scientists think this rock formed in the interior of Mars when magma moved up through cooler rock. As the magma cooled, elements including nickel, iron, and magnesium crystallized out of it first, leaving behind a material rich in silicon, aluminum, sodium, and potassium, as well as a higher fraction of dissolved water. Though the rock was unusual, the Curiosity team was careful to point out that it was just one isolated sample and not to extrapolate too much about early Martian geology based on it.

Engineers also discussed the case of the mysterious plastic object that Curiosity had spotted several days ago while scooping bits of Martian soil. They concluded that it is likely a bit of bonding material that fell off the rover or a piece of tubing that came off the descent stage and was recently blown off the probe. In either case, “it’s completely inconsequential to the rover’s function” and no further pieces have been seen, said engineer Chris Roumeliotis, the lead turret rover planner. Curiosity is continuing to go through its Martian dust rinse and repeat cycle to clean out its sample delivery instrument of any left-over contaminants from Earth.

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Mars Looks Quite Familiar, if Only on the Surface

A conspiracy theorist might think that NASA’s newest Mars rover, the Curiosity, is actually just in the middle of a desert on Earth.

Over the weekend, the Curiosity, which landed early on Aug. 6 after an eight-month flight, started sending back a 360-degree high-resolution panorama of its surroundings.

As the accompanying NASA news release noted, the images show “a landscape closely resembling portions of the southwestern United States.”

At a news conference on Wednesday, John P. Grotzinger, a professor of geology at the California Institute of Technology who serves as the mission’s project scientist, compared the view with a place just a few hours’ drive from Pasadena, Calif., and NASA’s Jet Propulsion Laboratory, the rover’s birthplace.

“You would really be forgiven for thinking that NASA was trying to pull a fast one on you,” he said, “and we actually put a rover out in the Mojave Desert and took a picture — a little L.A. smog coming in there.”

He added, “To a certain extent, the first impression you get is how Earth-like it seems.”

Where the Curiosity actually sits is a 96-mile-wide crater named Gale near the Martian equator.

To the north, the images show part of the crater rim that is believed to have been eroded by flowing water.

To the south is a 3.4-mile-high peak that the scientists call Mount Sharp, which Curiosity is meant to reach and to climb. By investigating the layers of sedimentary rock on Mount Sharp, mission scientists hope to reconstruct the climate and environment of early Mars and tell whether it could have been once been habitable for life.

The photos also show marks that Curiosity has made at the landing site. As Curiosity was lowered to the surface of Mars, blasts from the descent-stage engines created indentations in the nearby soil, exposing the bedrock below. This exposed bedrock is likely to be one of the first areas of scientific exploration on the rover’s planned two-year journey.

“What’s cool about this is that we got some free trenching,” Dr. Grotzinger said. After the flawless landing, the first week of operations of the rover on the ground also proceeded almost perfectly, too, as engineers started checking out the rover’s system, deployed the high-gain antenna, and raised the mast that holds the cameras.

So far, no significant trouble has arisen. The weather instrument experienced a problem that engineers figured out a day later.

The rover’s internal temperatures are slightly warmer than expected, possibly because the crater is warmer than predicted or because NASA’s computer models of Curiosity were not quite right.

“We’re still looking why that is,” said Jennifer Trosper, one of the mission managers.

Worries about overheating could put constraints on when certain instruments can be used. But the heat is also a boon, reducing the energy Curiosity needs to warm up its joints and wheels before moving.

Over the weekend, NASA upgraded the software that runs the rover’s computer.

On Monday morning, President Obama called to congratulate the Curiosity team. “You guys are examples of American know-how and ingenuity,” he said. “It’s really an amazing accomplishment.”

He did have one request for them: “If in fact you do make contact with Martians, please let me know right away,” the president said.

“I’ve got a lot of other things on my plate, but I suspect that that would go to the top of the list. Even if they’re just microbes, it will be pretty exciting.”

This article has been revised to reflect the following correction:

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Global greenhouse gas emissions continue to rise (+video)

International talks to address human-caused global warming began 20 years ago in Rio de Janeiro. But despite attempts to curb emissions of the greenhouse gases responsible, they have continued to pour into the atmosphere since then.

Last year was no exception.

In 2011, the burning of fossil fuels, as well as other activities such as cement and oil production, produced 3 percent more carbon dioxide in 2011, bringing this segment of emissions to an all-time 37.5 billion-ton (34 billion-metric tons) high that year, a European analysis reports. 

Top emitters

The past decade has seen a 2.7 percent annual increase in carbon dioxide emissions. China, the United States, the European Union, India, the Russian Federation and Japan rank as the top five emitters, from highest to lowest.

Last year's increase was driven by China and India, which saw their carbon dioxide emissions jump by 9 and 6 percent, respectively. Meanwhile, emissions from the European Union, the United States and Japan all decreased, according to the report, Trends in Global CO2 Emissions.

"Although all developing countries together increased their emissions on average by 6 percent, the increases in China and India caused by far the largest increase in global emissions," the report notes.

The report, by the Netherlands Environmental Assessment Agency and the E.U.'s Joint Research Centre, does not include carbon dioxide emitted by deforestation, forest fires and other land-use related activities. These sources could potentially add between 10 and 20 percent to the carbon dioxide emission figures, the authors write.

The authors also note that renewable energy technology, such as solar, wind and biofuels, accounts for a small share of energy sources; however they found its use is accelerating.

Carbon countdown

If global emissions of carbon dioxide continue to increase at their current rate, within two decades they will exceed the amount necessary to limit global warming to 3.6 degrees Fahrenheit (2 degrees Celsius), the target established in international negotiations, the authors of the report write. [How 2 Degrees Will Change Earth]

In late November and early December, international climate negotiators will converge in Doha,Qatar, to continue chipping away at this monumental problem.

Projections indicate limiting warming to 3.6 degrees F (2 degrees C) by 2100 will avert the worst of the many potentially devastating impacts of climate change, including sea-level rise, extreme weather and extinctions. However, scientists worry that this goal is becoming increasingly unrealistic as time passes.

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A hot, young spiral galaxy is the farthest yet seen

Artist's impression of spiral galaxy BX442 and its probable companion (top center). BX442 is the most distant spiral galaxy observed to date, at a distance of 10.7 billion light years.

Dunlap Institute for Astronomy & Astrophysics/Joe Bergeron

Spiral galaxies are common in the modern Universe: more than 75 percent of large galaxies are spirals. However, at cosmologically significant distances, they appear to be less common, indicating either that the conditions were wrong in the early Universe to create spiral structures, or current telescopes aren't good enough to distinguish the arms at those distances. A new observation has revealed a spiral galaxy about 10.7 billion light years away, the first unambiguous discovery of that type of galaxy from that cosmic era.

Using data from the Hubble Space Telescope and the Keck telescope in Hawaii, David R. Law and colleagues characterized the object labeled BX442 as a "grand design" spiral galaxy. In grand design spirals, the spiral arms are clearly defined and wind significantly around the galactic center.

The authors turned up BX442 in a survey of 306 galaxies at a similar distance from Earth, but it was the only one with obvious spiral morphology (the technical term for the general shape a galaxy takes). While a second galaxy, HDFX 28, appeared spiral in another sample and is approximately as far away, its spiral shape may be an illusion, based on the angle at which it appears to us. Even if HDFX 28 is truly spiral, the apparent number of spiral galaxies at that era in the Universe's history is still small.

Light from distant galaxies is redshifted—stretched by the expansion of spacetime to longer wavelengths. This means that visible light from distant galaxies will appear in the infrared part of the spectrum to observers on Earth

The researchers used infrared data from the Hubble Space Telescope's Wide-Field Camera 3 (WFC3) and from the Keck OSIRIS spectrograph to characterize BX442's structure. They identified two distinct arms and a probable third arm using emission from stars and ionized hydrogen gas. Spiral arms in modern galaxies trace the presence of star formation and the hottest, youngest stars, which also seems to be the case with BX442. In fact, based on analysis with the Keck ultraviolet Low Resolution Imaging Spectrometer (LRIS), BX442 is hotter than comparable modern galaxies. The temperature is measured by the velocity of gas inside the galaxy, relative to the rotation rate of the galactic disk.

Other galaxies at cosmologically significant distances have similar masses, sizes, and disk structure, but lack spiral arms. To explain the difference, the authors pointed out the presence of a close companion galaxy, seen in the image at the top of this article, which may have disturbed BX442. Such perturbations are considered to be the source of structure in modern grand design spiral galaxies.

Because of the transient nature of gravitational disturbances, the researchers pointed out that BX442's spiral arms may have been a temporary feature. If that was the case, it would also help explain why no other galaxies in the sample of 306 possessed spiral arms: they hadn't experienced a close passage within the time frame of the observation. However, it isn't possible to rule out selection effects entirely: BX442 is nearly face-on to Earth and very clear, but at the huge distances, not every galaxy is as beautifully defined.

Due to its extreme distance, BX442 is the earliest confirmed spiral galaxy in the Universe, and future study will reveal how unusual it is. Existing instruments on the Hubble and Keck telescopes were able to find and characterize a spiral galaxy unambiguously. Further surveys at this great distance should help settle whether BX442 is unique, or part of a larger population from the early days of galaxy formation in the Universe.

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Huge iceberg breaks off from glacier in north Greenland, just as predicted (+video)

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An iceberg twice the size of Manhattan tore off one of Greenland's largest glaciers.

In this 2007 photo, an iceberg is seen melting off the coast of Ammasalik, Greenland.

For several years, scientists had been watching a long crack in the floating ice shelf of the northerlyPetermann Glacier. On Monday, NASA satellites showed it had broken completely, forming an iceberg covering 46 square miles (120 sq. kilometers).

The same glacier spawned an iceberg twice that size two years ago.

Researchers suspect global warming is to blame, but cannot prove it conclusively yet. Many of Greenland's southern glaciers have been melting at an unusually rapid pace. Government scientist Ted Scambos says this break brings large ice loss much farther north.

Scientists also reported that the Arctic had the largest sea ice loss on record for June.

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Study: Swirling Eddies Trigger Plankton Bloom in North Atlantic

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On a recent expedition to the inhospitable North Atlantic Ocean, scientists at the University of Washington and collaborators studying the annual growth of tiny plants were stumped to discover that the plankton had started growing before the sun had a chance to offer the light they need for their growth spurt.

For decades, scientists have known that springtime brings the longer days and calmer seas that force phytoplankton near the surface, where they get the sunlight they need to flourish.

But in research results published this week in the journal Science, scientists report evidence of another trigger.

Eric D’Asaro and Craig Lee, oceanographers in the UW’s Applied Physics Laboratory and School of Oceanography, are among the researchers who found that whirlpools, or eddies, that swirl across the North Atlantic sustain phytoplankton in the ocean’s shallower waters, where the plankton can get plenty of sunlight to fuel their growth even before the longer days of spring start.

The eddies form when heavier, colder water from the north slips under the lighter, warmer water from the south. The researchers found that the eddies cause the bloom to happen around three weeks earlier than it would if it was spurred just by spring’s longer days.

“That timing makes a significant difference if you think about the animals that eat the phytoplankton,” said D’Asaro, the corresponding author on the paper.

Many small sea animals spend the winter dozing in the deep ocean, emerging in the spring and summer to feed on the phytoplankton.

“If they get the timing wrong, they’ll starve,” Lee said. Since fish eat the animals, a reduction in their number could harm the fish population.

Scientists believe that climate change may affect oceanic circulation patterns such as the one that causes the eddies. They’ve found some evidence that warm waters from the subtropics are penetrating further to the north, Lee said.

“If the climate alters the circulation patterns, it might alter the timing of the bloom, which could impact which animals grow and which die out,” he said.

Learning about the circulation of the ocean also helps scientists forecast changes in the ocean, a bit like meteorologists are able to forecast the weather, said D’Asaro.

The scientists didn’t set out to look at the kind of large-scale mixing that they found. In April 2008, Lee and co-author Mary Jane Perry of the University of Maine arrived in a storm-lashed North Atlantic aboard an Icelandic research vessel.

They launched robots (specially designed by Lee and D’Asaro) in the rough seas. A float that hovered below the water’s surface followed the motion of the ocean, moving around “like a giant phytoplankton,” said D’Asaro.

Lurking alongside the float were 6-foot-long, teardrop-shaped Seagliders, also designed at the UW, that dove to depths of up to 1,000 meters, or 3,280 feet.  After each dive, working in areas 20 to 50 kilometers, or 12 to 31 miles, around the float, the gliders rose to the surface, pointed their antennas skyward and transmitted their stored data back to shore via satellite.

The float and gliders measured the temperature, salinity and speed of the water, and gathered information about the chemistry and biology of the bloom itself.  Soon after measurements from the float and gliders started coming in, the scientists saw that the bloom had started, even though conditions still looked winter-like.

“It was apparent that some new mechanism, other than surface warming, was behind the bloom’s initiation,” said D’Asaro.

To find out what, the researchers needed sophisticated computer modeling.

Enter first author Amala Mahadevan, with Woods Hole Oceanographic Institution, who used 3-D computer models to look at information collected at sea by Perry, D’Asaro and Lee.

She generated eddies in a model using the north-to-south oceanic temperature variation. Without eddies, the bloom happened several weeks later and didn’t have the space and time structures actually observed in the North Atlantic.

In the future, the scientists hope to put the North Atlantic bloom into a broader context. They believe much can be learned by following the phytoplankton’s evolution across an entire year, especially with gliders and floats outfitted with new sensors. The sensors would look at the tiny animals that graze on the phytoplankton.

“What we’re learning about eddies is that they’re a critical part of life in the ocean,” said Perry. “They shape ocean ecosystems in countless ways.”

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