Supermom Primates Raise Twins

The first occurrence of twins for free-ranging Tibetan macaques has just been documented, revealing how rare survivorship of twins can be in many primate species, and how important mothers are to their success.

It’s possible that only supermom primates, humans included, can properly raise twins. In the wild, twins often die shortly after birth, or only one lives into adulthood.

In the case of the Tibetan macaque mother of twins, described in the latest issue of the journal Primates, there is little doubt that she was qualified for the task.

“She appeared to remain quite healthy,” co-author Megan Matheson told Discovery News. “I was very impressed when I observed her in August of 2010 running with two, by now quite large, infants hanging on!”

“At last check, the twins were still alive,” added Matheson, a professor of psychology at Central Washington University. “They would be not quite 2 years old now, so still in the young juvenile stage. The twins were males, so they are not considered to be adults until 7 years of age.”

Matheson and her colleagues discovered the twins among a group of free-ranging Tibetan macaques at Huangshan, China. They studied the mother for 5 months after the birth, comparing her activities to those of other adult females with single or no offspring.

The researchers found that the mother monkey with twins spent more time foraging and resting, but that the quality of her social interactions did not seem to differ much from that of other macaque females.

In fact, she seemed to enjoy showing off her twins to others, who displayed an interest in the youngsters. For some reason, she tended to present one twin more frequently than its sibling. The researchers are not certain if that was because she is right handed, and simply handed over the twin on her right side more, or if she preferred that particular individual.

Males for this primate species, and many others, do not share parental duties. Female Tibetan macaques may mate with multiple males during the primary mating season.

“Dominant males have priority of access, but more subordinate males may sneak copulations,” Matheson said. As a result, paternity can be uncertain.

“Generally speaking, in these species where paternity uncertainty is the norm, adult males will be protective of all infants if they are threatened, but don’t necessarily favor any one for special contact,” she continued.

Some female primates help out in what’s called “aunting behavior,” but that doesn’t happen much among Tibetan macaques. Matheson suspects it’s because “the mothers are not overly protective, and thus give the infants a lot of freedom once they’re able to move about independently. Even when they’re still nursing, the mother will retrieve infants when she leaves an area, but the infant is often exploring or playing with others while his or her mother forages.”

Successful parenting of twins among all non-human primates is rare, save for one family of South American monkeys, the Callitrichidae, which includes tamarins and marmosets. Females of this primate family routinely give birth to twins, with males providing substantial care. Sometimes mothers and dads of these primates will even raise triplets.

Among humans, studies reveal that women who deliver twins live longer, have more children than expected, bear babies at shorter intervals over a longer time, and are older at their last birth.

Read more at Discovery News

Was First Winged Dinosaur Jet Black?

The winged dinosaur Archaeopteryx, which may represent the missing link in birds' evolution to powered flight, had at least some jet-black feathers, according to new research published today in Nature Communications.

Aside from creating more of a cool visual for this raven-sized animal, the discovery suggests that Archaeopteryx could fly, since the color and parts of cells that would have supplied the black pigment are evidence that the wing feathers were rigid and durable. These are traits that probably would have permitted flight.

The research team, led by evolutionary biologist Ryan Carney of Brown University, made another important discovery. The feather structure of Archaeopteryx turns out to have been identical to that of living birds, providing strong evidence that wing feathers evolved as early as 150 million years ago during the Jurassic Period.

"If Archaeopteryx was flapping or gliding, the presence of melanosomes [pigment-producing parts of a cell] would have given the feathers additional structural support," Carney was quoted as saying in a press release. "This would have been advantageous during this early evolutionary stage of dinosaur flight."

Archaeopteryx has been at the center of debate between scientists, who squabble over whether the animal was a non-avian dinosaur or a bird. It could have even been an intermediary between the two.

As for the feather, it was discovered in a limestone deposit in Germany in 1861, a few years after the publication of Charles Darwin's On the Origin of Species. Thinking of Darwin ... the traits that might make Archaeopteryx an evolutionary intermediate between dinosaurs and birds are the combination of reptilian  (teeth, clawed fingers and a bony tail) and avian (feathered wings and a wishbone) features.

Carney and his team patiently used a scanning electron microscope to locate patches of hundreds of the pigment structures, the melanosomes, still encased in the fossilized feather.

"The third time was the charm, and we finally found the keys to unlocking the feather's original color, hidden in the rock for the past 150 million years," said Carney.

The scientists also examined fossilized barbules within the feather. These are tiny, rib-like appendages that overlap and interlock like zippers to give a feather rigidity and strength. The barbules and the alignment of melanosomes within them, Carney said, are all identical to those found in modern birds.

The black coloration offers possible clues about the behavior of Archaeopteryx. Black can serve to regulate body temperature, act as camouflage, be employed for display and, again, support flight.

Read more at Discovery News

Hundreds of Meteorites Uncovered in Antarctica

A gang of heavily insulated scientists has wrapped up its Antarctic expedition, with its members thawing out from the experience, but pleased to have bagged more than 300 space rocks.

They are participants in the Antarctic Search for Meteorites program, or ANSMET for short. Since 1976, ANSMET researchers have been recovering thousands of meteorite specimens from the East Antarctic ice sheet. ANSMET is funded by the Office of Polar Programs of the National Science Foundation.

According to the ANSMET website, the specimens are currently the only reliable, continuous source of new, nonmicroscopic extraterrestrial material. Given that there are no active planetary sample-return missions coming or going at the moment, the retrieval of meteorites is the cheapest and only guaranteed way to recover new things from worlds beyond the Earth.

Special place

"It has been another interesting season at Miller Range," said Ralph Harvey, associate professor in the department of Earth, Environmental and Planetary Sciences at Case Western Reserve University in Cleveland, Ohio.

"The place is special for us because we seem to find meteorites everywhere, in every little nook and cranny, almost unpredictable," Harvey told SPACE.com. "And it did it again ... lots of places we checked out just to be complete proved to have dozens of specimens."

Harvey is the principal investigator for the ANSMET program. "I've been leading field parties since 1991 and I think this year marks my 25th overall with the program," Harvey said.

Harvey likens his search for meteorites to a farmer who's used to harvesting corn in a field finding it growing in the barn, in the garage, in the basement and other surprising spots.

The meteorite hunting wasn't all smooth, though.

The team was held back significantly by early snowfalls that buried the meteorites. Even though a few strong windstorms cleared some of it, the whipping winds did not clear all of it, Harvey explained.

"The total number of meteorites is less than half what I would have predicted, again primarily because of that early snow hiding all the specimens," Harvey said. "We'll be going back to the Miller Range at least one more time and maybe two."

Celestial collectibles

Antarctica is viewed as the world's premier meteorite hunting ground, and for good reason.

While meteorites fall in a random fashion all over the globe, the East Antarctic ice sheet is a "desert of ice," a stark scene that enhances the likelihood of finding meteorites, which are usually undisturbed and stand out against the background.

In the just-concluded search, the team's bounty of celestial collectibles brought the total number of meteorites found in ANSMET history to 20,000.

Along with Harvey, the meteorite hunters are:

John Schutt, an ANSMET mountaineer for over 30 years who once again played that role. He recently got an honorary doctorate recognizing his contributions to planetary science.

Jim Karner, a postdoctoral researcher working with the ANSMET program and a specialist in Martian meteorites from Case Western Reserve. He's a veteran of four ANSMET expeditions.

Christian Schrader, a geologist from NASA Marshall Space Flight Center in Huntsville, Ala., who has done significant rock work, particularly in studying lunar meteorites.

Katie Joy, planetary geologist, most recently from the Lunar and Planetary Institute in Houston, Tex., and a lunar meteorite researcher.

Anne Peslier, a planetary scientist from NASA's Johnson Space Center in Houston who has done a great deal of work on Martian meteorites.

Jake Maule, a planetary scientist, recently of Carnegie Institute in Washington, D.C., with a specialty in astrobiology.

Jesper Holst, a Ph.D. student studying planetary geochemistry at the University of Copenhagen.

Tim Swindle, a planetary geochemist from the University of Arizona, taking part in the second half of the season, and a veteran of several previous expeditions.

Read more at Discovery News

Waiting for Death Valley's Next Big Bang

California’s Death Valley comes by its morbid reputation honestly, but not for the reason you might think. True, this stark desert holds the record for the hottest, driest spot in North America. Scientists now say it also poses a different threat: spectacularly explosive volcanic eruptions.

A new study from geochemists at Columbia University’s Lamont-Doherty Earth Observatory reveals that around the year 1300, a volcanic explosion in the northern part of the valley ripped a half-mile-wide hole in the overlying sedimentary rock, blasting out superheated steam, volcanic ash and deadly gases. Study co-author Brent Goehring, now at Purdue University, described this dramatic event yesterday in a press release:

    …this would have created an atom-bomb-like mushroom cloud that collapsed on itself in a donut shape, then rushed outward along the ground at some 200 miles an hour, as rocks hailed down. Any creature within two miles or more would be fatally thrown, suffocated, burned and bombarded, though not necessarily in that order.

In the new report, published in the 18 January issue of Geophysical Research Letters, Goehring and his colleagues suggest such an event created Ubehebe (pronounced YOU-bee-HEE-bee) volcanic crater, the youngest and largest of a dozen similar craters in northern Death Valley.

What's more, conditions may be ripe for a repeat performance.

Geologists had long assumed that Ubehebe and its sister craters were thousands (or even tens of thousands) of years old. Those supposed ages would put the eruptions at the end of the last ice age, when the U.S. southwest was considerably wetter than it is today. And that made perfect sense, considering all geologic clues suggest the magma mixed with water, which is what made them so explosive.

Called phreatomagmatic eruptions, such events usually occur where water is abundant—near the edge of a lake, say, or at the bottom of the ocean.

But when the Lamont geochemists used a new-fangled isotope technique to date the volcanic craters, they turned out to be surprisingly young. They ranged from 2,100 years old to 800 years old—meaning they formed long after California had dried out.

That left the researchers with only groundwater to blame. Indeed, the present-day water table is relatively shallow, probably only 150 meters below the floor of Ubehebe crater. “This and the youth of the most recent activity suggest that the Ubehebe volcanic field may constitute a more significant hazard than generally appreciated,” the researchers concluded.

This bold, new statement stems from the remarkable ability of quartz-rich pebbles, which now litter the desert soil around the craters, to track the time since an explosion ripped them out of the ground. Ever since that moment, cosmic rays striking certain oxygen atoms within the quartz grains have been creating radioactive beryllium-10, a so-called cosmogenic nuclide with a known rate of decay.

Measuring beryllium-10 is the basis for a dating technique similar to one Dutch scientists used recently to hone in on the date of a prehistoric tsunami based on the grains of sand the storm washed to shore.

Read more at Discovery News

New Understanding of Chronic Pain

Millions of people worldwide suffer from a type of chronic pain called neuropathic pain, which is triggered by nerve damage. Precisely how this pain persists has been a mystery, and current treatments are largely ineffective. But a team led by scientists from The Scripps Research Institute, using a new approach known as metabolomics, has now discovered a major clue: dimethylsphingosine (DMS), a small-molecule byproduct of cellular membranes in the nervous system. In their new study, the scientists found that DMS is produced at abnormally high levels in the spinal cords of rats with neuropathic pain and appears to cause pain when injected. The findings suggest inhibiting this molecule may be a fruitful target for drug development.

"We think that this is a big step forward in understanding and treating neuropathic pain, and also a solid demonstration of the power of metabolomics," said Gary J. Patti, a research associate at Scripps Research during the study, and now an assistant professor of genetics, chemistry, and medicine at Washington University in St. Louis. Patti is a lead author of the report on the study, which appeared online in the journal Nature Chemical Biology on January 22, 2012.

Scientists who want to understand what makes diseased cells different from healthy cells have often looked for differences in levels of gene expression or cellular proteins -- approaches known respectively as genomics and proteomics. Metabolomics, by contrast, concerns differences in the levels of small-molecule metabolites, such as sugars, vitamins, and amino acids, that serve as the building blocks of basic cellular processes. "These are the molecules that are actually being transformed during cellular activity, and tracking them provides more direct information on what's happening at a biochemical level," Patti said.

Metabolomics is increasingly used to find biochemical markers or signatures of diseases. One of the most relied-upon "metabolome" databases, METLIN, was set up at Scripps Research in 2005, and now contains data on thousands of metabolites found in humans and other organisms. However, in this case the research team hoped to do more than find a metabolic marker of neuropathic pain.

"The idea was to apply metabolomic analysis to understand the biochemical basis of the neuropathic pain condition and reveal potential therapeutic targets," said Gary Siuzdak, a senior investigator in the study, who is professor of chemistry and molecular biology and director of the Scripps Research Center for Metabolomics. "We call this approach 'therapeutic metabolomics'."

The scientists began with a standard model of neuropathic pain in lab rats. Patti, Siuzdak, and their colleagues sampled segments of a previously injured tibial leg nerve triggering neuropathic pain, as well as the rats' blood plasma and tissue from the rats' spinal cords. The scientists then determined the levels of metabolites in these tissues, and compared them to levels from control animals.

Unexpectedly, the scientists found that nearly all the major abnormalities in metabolite levels were present not in the injured leg nerve fiber, nor in blood plasma, but in tissue from the "dorsal horn" region of the spinal cord which normally receives signals from the tibial nerve and relays them to the brain. "After the nerve is damaged, it degrades and rebuilds itself at the site of the injury, but remodeling also occurs, possibly over a longer period, at the terminus of the nerve where it connects to dorsal horn neurons," Patti said.

Next, the researchers set up a test to see which of the abnormally altered metabolites in dorsal horn tissue could evoke signs of pain signaling in cultures of rat spinal cord tissue. One metabolite stood out -- a small molecule that didn't appear in any of the metabolome databases. Patti eventually determined that the molecule was DMS, an apparent byproduct of cellular reactions involving sphingomyelin, a major building block for the insulating sheaths of nerve fibers. "This is the first characterization and quantitation of DMS as a naturally occurring compound," Patti noted. When the scientists injected it into healthy rats, at a dose similar to that found in the nerve-injured rats, it induced pain.

DMS seems to cause pain at least in part by stimulating the release of pro-inflammatory molecules from neuron-supporting cells called astrocytes. Patti, Siuzdak, and their colleagues are now trying to find out more about DMS's pain-inducing mechanisms -- and are testing inhibitors of DMS production that may prove to be effective treatments or preventives of neuropathic pain.

"We're very excited about this therapeutic metabolomics approach," said Siuzdak. "In fact, we're already involved in several other projects in which metabolites are giving us a direct indication of disease biochemistry and potential treatments."

Read more at Science Daily

Mysterious 'Winged' Structure from Ancient Rome Found

A recently discovered mysterious "winged" structure in England, which in the Roman period may have been used as a temple, presents a puzzle for archaeologists, who say the building has no known parallels.

Built around 1,800 years ago, the structure was discovered in Norfolk, in eastern England, just to the south of the ancient town of Venta Icenorum. The structure has two wings radiating out from a rectangular room that in turn leads to a central room.

"Generally speaking, [during] the Roman Empire people built within a fixed repertoire of architectural forms," said William Bowden, a professor at the University of Nottingham, who reported the find in the most recent edition of the Journal of Roman Archaeology. The investigation was carried out in conjunction with the Norfolk Archaeological and Historical Research Group.

The winged shape of the building appears to be unique in the Roman Empire, with no other example known. "It's very unusual to find a building like this where you have no known parallels for it," Bowden told LiveScience. "What they were trying to achieve by using this design is really very difficult to say."

The building appears to have been part of a complex that includes a villa to the north and at least two other structures to the northeast and northwest. An aerial photograph suggests the existence of an oval or polygonal building with an apse located to the east.

The foundation of the two wings and the rectangular room was made of a thin layer of rammed clay and chalk. "This suggests that the superstructure of much of the building was quite light, probably timber and clay-lump walls with a thatched roof," writes Bowden. This raises the possibility that the building was not intended to be used long term.

The central room, on the other hand, was made of stronger stuff, with its foundations crafted from lime mortar mixed with clay and small pieces of flint and brick. That section likely had a tiled roof. "Roman tiles are very large things, they’re very heavy," Bowden said.

Sometime after the demise of this wing-shaped structure, another building, this one decorated, was built over it. Archaeologists found post holes from it with painted wall plaster inside.

Bowden said few artifacts were found at the site and none that could be linked to the winged structure with certainty. A plough had ripped through the site at some point, scattering debris. Also, metal detecting is a major problem in the Norfolk area, with people using metal detectors to locate and confiscate materials, something that may have happened at this site.

Still, even when the team found undisturbed layers, there was little in the way of artifacts. "This could suggest that it [the winged building] wasn't used for a very particularly long time," Bowden said.

Researchers are not certain what the building was used for. While its elevated position made it visible from the town of Venta Icenorum, the foundations of the radiating wings are weak. "It's possible that this was a temporary building constructed for a single event or ceremony, which might account for its insubstantial construction,' writes Bowden in the journal article.

"Alternatively the building may represent a shrine or temple on a hilltop close to a Roman road, visible from the road as well as from the town."

Adding another layer to this mystery is the ancient history of Norfolk, where the structure was found.

The local people in the area, who lived here before the Roman conquest, were known as the Iceni. It may have been their descendents who lived at the site and constructed the winged building.

Iceni architecture was quite simple and, as Bowden explained, not as elaborate as this. On the other hand, their religion was intertwined with nature, something which may help explain the wind-blown location of the site. "Iceni gods, pre-Roman gods, tend to be associated with the natural sites: the springs, trees, sacred groves, this kind of thing," said Bowden.

The history between the Iceni and the Romans is a violent one. In A.D. 43, when the Romans, under Emperor Claudius, invaded Britain, they encountered fierce resistance from them.  After a failed revolt in A.D. 47 they became a client kingdom of the empire, with Prasutagus as their leader. When he died, around A.D. 60, the Romans tried to finish the subjugation, in brutal fashion.

"First, his [Prasutagus'] wife Boudicea was scourged, and his daughters outraged. All the chief men of the Iceni, as if Rome had received the whole country as a gift, were stripped of their ancestral possessions, and the king's relatives were made slaves," wrote Tacitus, a Roman writer in The Annals.  (From the book, "Complete Works of Tacitus," 1942, edited for the Perseus Digital Library.)

This led Boudicea (more commonly spelled Boudicca) to form an army and lead a revolt against the Romans. At first she was successful, defeating Roman military units and even sacking Londinium. In the end the Romans rallied and defeated her at the Battle of Watling Street. With the Roman victory the rebellion came to an end, and a town named Venta Icenorumwas eventually set up on their land.

Read more at Discovery News

Dinosaurs were caring mothers, new discovery finds

The finding in South Africa showed several clutches of fossilised eggs, many containing embryos.

Tiny footprints of the newborn dinosaurs also showed they stayed in the nest long enough to grow to double their size.

The nests, found in Golden Gate Highlands National Park, is 100 million years older than previously found nests and belonged to Massospondylus, a 20-foot ancestor of long-necked "sauropod" dinosaurs that lived 190 million years ago.

At least 10 nests were found at different rock levels, with up to 34 eggs in each, suggesting the dinosaurs returned to the same spot to lay their eggs.

The research appeared in the journal Proceedings of the National Academy of Sciences (PNAS).

"Even though the fossil record of dinosaurs is extensive, we actually have very little fossil information about their reproductive biology, particularly for early dinosaurs," said leading scientist Dr David Evans, curator of vertebrate palaeontology at the Royal Ontario Museum in Canada.

Read more at The Telegraph

INCOMING! Sun Blasts Another CME at Earth and Mars

You may not know it, but there's an epic magnetic battle between the sun and Earth raging over our heads.

On Friday, the sun hurled a coronal mass ejection (CME) at our planet that sparked a strong geomagnetic storm and beautiful aurorae at high latitudes on Sunday. Late last night (EST), the sun unleashed yet another CME... and it's heading our way.

One Fast-Moving CME Coming Right Up

A particularly angry-looking sunspot (1402) on the solar surface erupted with a strong, long-duration M9-class flare Sunday night at around 11 p.m. EST. "M" stands for "medium," but the explosive energy was just shy of an X-class solar flare -- the strongest kind of flare the sun can produce.

This flare was accompanied by a fast-moving CME that jetted from the lower solar atmosphere and is currently heading our way. Space weather researchers predict the CME will impact our planet's magnetosphere tomorrow (Jan. 24). It will then plough into Mars the following day.

Now that yet another CME is approaching, even more spectacular auroral activity can be expected for the next few nights. We are currently undergoing the largest solar radiation storm since 2005.

"SWPC (Space Weather Prediction Center) has issued a Geomagnetic Storm Watch with G2 level storming likely and G3 level storming possible, with the storm continuing into Wednesday, Jan. 25," the NOAA announced on Monday.

Living With A Star

All these flares, CMEs, space radiation and aurorae may sound scary, but it's all a natural consequence of living with a star.

As our sun approaches "solar maximum" -- a time of maximum magnetic activity in its 11-year cycle -- we can expect more solar flares and CMEs, some of which will hit the Earth. The next solar maximum is predicted to occur in 2013, so we have a few more months of solar excitement to come.

Our planet is more than capable of protecting us from a solar radiation battering. We live in a dense atmosphere that can absorb ionizing X-ray radiation from the most powerful of flares. Also, our planet has a natural magnetic "force field" (the magnetosphere) that deflects energetic solar particles from CMEs. The particles are funneled toward Polar Regions by the magnetosphere where they collide with our dense atmosphere, generating beautiful auroral displays.

Although solar radiation may not be a direct threat to life on Earth, it can cause problems with sensitive electronics in space. Communications satellites in geosynchronous orbit, for example, are especially vulnerable to solar radiation -- there will no doubt be some nervous satellite operators watching the NOAA's SWPC website over the coming hours and days.

Increased solar radiation can also affect unprotected astronauts in orbit, although no problems are expected during this event. "The flight surgeons have reviewed the space weather forecasts for the flare and determined that there are no expected adverse effects or actions required to protect the on-orbit crew," NASA spokesman Kelly Humphries told Discovery News.

The latest geomagnetic storm also generated powerful currents through our atmosphere over the weekend. These currents are generated when charged particles from impacting CMEs rain down through our atmosphere. Occasionally, if powerful enough, these currents can knock out power grids on the ground -- a rare scenario that knocked out the Hydro-Québec's power grid during a geomagnetic storm in 1989.

Read more at Discovery News

Unveiling Malaria's 'Cloak of Invisibility'

The discovery by researchers from the Walter and Eliza Hall Institute of a molecule that is key to malaria's 'invisibility cloak' will help to better understand how the parasite causes disease and escapes from the defences mounted by the immune system.

The research team, led by Professor Alan Cowman from the institute's Infection and Immunity division, has identified one of the crucial molecules that instructs the parasite to employ its invisibility cloak to hide from the immune system, and helps its offspring to remember how to 'make' the cloak.

In research published in the journal Cell Host & Microbe, Professor Cowman and colleagues reveal details about the first molecule found to control the genetic expression of PfEMP1 (Plasmodium falciparum erythrocyte membrane protein 1), a protein that is known to be a major cause of disease during malaria infection.

"The molecule that we discovered, named PfSET10, plays an important role in the genetic control of PfEMP1; an essential parasite protein that is used during specific stages of parasite development for its survival," Professor Cowman said.

"This is the first protein that has been found at what we call the 'active' site, where control of the genes that produce PfEMP1 occurs. Knowing the genes involved in the production of PfEMP1 is key to understanding how this parasite escapes the defenses deployed against it by our immune system," he said.

PfEMP1 plays two important roles in malaria infection. It enables the parasite to stick to cells on the internal lining of blood vessels, which prevents the infected cells from being eliminated from the body. It is also responsible for helping the parasite to escape destruction by the immune system, by varying the genetic code of the PfEMP1 protein so that at least some of the parasites will evade detection. This variation lends the parasite the 'cloak of invisibility' which makes it difficult for the immune system to detect parasite-infected cells, and is part of the reason a vaccine has remained elusive.

Professor Cowman said identification of the PfSET10 molecule was the first step towards unveiling the way in which the parasite uses PfEMP1 as an invisibility cloak to hide itself from the immune system. "As we better understand the systems that control how the PfEMP1 protein is encoded and produced by the parasite, including the molecules that are involved in controlling the process, we will be able to produce targeted treatments that would be more effective in preventing malaria infection in the approximately 3 billion people who are at risk of contracting malaria worldwide," he said.

Each year more than 250 million people are infected with malaria and approximately 655,000 people, mostly children, die. Professor Cowman has spent more than 30 years studying Plasmodium falciparum, the most lethal of the four Plasmodium species, with the aim of developing new vaccines and treatments for the disease.

Read more at Science Daily

Catching a Comet Death On Camera

On July 6, 2011, a comet was caught doing something never seen before: die a scorching death as it flew too close to the sun. That the comet met its fate this way was no surprise -- but the chance to watch it first-hand amazed even the most seasoned comet watchers.

"Comets are usually too dim to be seen in the glare of the sun's light," says Dean Pesnell at NASA's Goddard Space Flight Center in Greenbelt, Md., who is the project scientist for NASA's Solar Dynamic Observatory (SDO), which snapped images of the comet. "We've been telling people we'd never see one in SDO data."

But an ultra bright comet, from a group known as the Kreutz comets, overturned all preconceived notions. The comet can clearly be viewed moving in over the right side of the sun, disappearing 20 minutes later as it evaporates in the searing heat. The movie is more than just a novelty. As detailed in a paper in Science magazine appearing January 20, 2012, watching the comet's death provides a new way to estimate the comet's size and mass. The comet turns out to be somewhere between 150 to 300 feet long and have about as much mass as an aircraft carrier.

"Of course, it's doing something very different than what aircraft carriers do," says Karel Schrijver, a solar scientist at Lockheed Martin in Palo Alto, Calif., who is the first author on the Science paper and is the principal investigator of the Atmospheric Imaging Assembly instrument on SDO, which recorded the movie. "It was moving along at almost 400 miles per second through the intense heat of the sun -- and was literally being evaporated away."

Typically, comet-watchers see the Kreutz-group comets only through images taken by coronagraphs, a specialized telescope that views the Sun's fainter out atmosphere, or corona, by blocking the direct blinding sunlight with a solid occulting disk. On average a new member of the Kreutz family is discovered every three days, with some of the larger members being observed for some 48 hours or more before disappearing behind the occulting disk, never to be seen again. Such "sun-grazer" comets obviously destruct when they get close to the sun, but the event had never been witnessed.

The journey to categorizing this comet began on July 6, 2011 after Schrijver spotted a bright comet in a coronagraph produced by the SOlar Heliospheric Observatory (SOHO). He looked for it in the SDO images and much to his surprise he found it. Soon a movie of the comet circulated to comet and solar scientists, eventually making a huge splash on the Internet as well.

Karl Battams, a scientist with the Naval Research Laboratory in Washington, DC, who has extensively observed comets with SOHO and is also an author on the paper, was skeptical when he first received the movie. "But as soon as I watched it, there was zero doubt," he says. "I am so used to seeing comets simply disappearing in the SOHO images. It was breathtaking to see one truly evaporating in the corona like that."

After the excitement, the scientists got down to work. Humans have been watching and recording comets for thousands of years, but finding their dimensions has typically required a direct visit from a probe flying nearby. This movie offered the first chance to measure such things from afar. The very fact that the comet evaporated in a certain amount of time over a certain amount of space means one can work backward to determine how big it must have been before hitting the sun's atmosphere.

The Science paper describes the comet and its last moments as follows: It was traveling some 400 miles per second and made it to within 62,000 miles of the sun's surface before evaporating. Before its final death throes, in the last 20 minutes of its existence when it was visible to SDO, the comet was some 100 million pounds, had broken up into a dozen or so large chunks with sizes between 30 to 150 feet, embedded in a "coma" -- that is the fuzzy cloud surrounding the comet -- of approximately 800 miles across, and followed by a glowing tail of about 10,000 miles in length.

It is actually the coma and tail of the comet being seen in the video, not the comet's core. And close examination shows that the light in the tail pulses, getting dimmer and brighter over time. The team speculates that the pulsing variations are caused by successive breakups of each of the individual chunks that made up the comet material as it fell apart in the Sun's intense heat.

"I think this is one of the most interesting things we can see here," says Lockheed's Schrijver. "The comet's tail gets brighter by as much as four times every minute or two. The comet seems first to put a lot of material into that tail, then less, and then the pattern repeats." Figuring out the exact details of why this happens is but one of the mysteries remaining about this comet movie. High on the list is to answer the not-so-simple question of why we can see the comet at all. Certainly, there are a few basic characteristics of this situation that help. For one, this comet was big enough to survive long enough to be seen, and its orbit took it right across the face of the Sun. It was also, says Battams, probably one of the top 15 brightest comets seen by SOHO, which has observed over 2,100 sun-grazing comets to date. The SDO cameras, in of themselves, also contributed a great deal: despite being far away and relatively small compared to the sun, the comet showed up clearly on SDO's high definition imager. This imager, called the Atmospheric Imaging Assembly (AIA) takes a picture every 12 seconds so the movement of the comet across the face of the sun could be continuously watched. Most other similar instruments capture images every few minutes, which makes it hard to track the movement of an object that's only visible for 20 minutes.

Read more at Science Daily