Memory activation before exposure reduces life-long fear of spiders

By disrupting the recreation of fear memories, exposure therapy can be made more effective for anxiety disorder patients, suggests a new report.

Many people suffer from anxiety and fears, and a common treatment for these problems is exposure therapy. In a new study published in Current Biology, researchers at Uppsala University have shown how the effect of exposure therapy can be improved by disrupting the recreation of fear-memories in people with arachnophobia.

Studies show that up to 30 per cent of all people suffer an anxiety disorder at some point in their lives. Anxiety leads to great suffering for those affected, but can be treated with exposure therapy, in which the patient is gradually exposed to the object or context that provokes the reactions. If exposure therapy is successful, a new 'safe' memory is formed, which overshadows the old fear memory. But not everyone is helped by this treatment, in part because the learning that takes place during the treatment is not permanent; the memory may return at some point later on after an initially successful exposure. Memory researchers have now demonstrated that the improvement can be made more lasting.

When a person is reminded of something, the memory becomes unstable and is re-saved. If you disrupt the re-saving of the memory, so-called reconsolidation, the creation of the memory can be disrupted and the memory that is saved can be changed. A fear memory could thus be weakened or erased, and this offers hope for improved treatment of anxiety disorders. But until now there has been doubt if this would be possible because older and stronger memories have proven to be difficult to disrupt.

In a study published in the journal Current Biology, researchers from Uppsala University and Karolinska Institutet in Sweden have now for the first time shown that it is possible to use this method to reduce fear in life-long phobias. The researchers exposed individuals with arachnophobia to spider pictures while measuring their brain activity in the amygdala, a part of the brain that is strongly linked to fear.

They found that an activation of the fear memory, consisting of a mini-exposure 10 minutes before a more extensive exposure, led to significantly reduced amygdala activity when the subjects looked at the spider pictures again the following day. Because the memory is made unstable before exposure and re-saved in its weakened form, the fear does not return as easily. The day after exposure, the group that received an initial activation of their spider fear showed reduced amygdala activity in comparison with a control group. Avoidance of spiders also decreased, which could be predicted from the degree of amygdala activation.

'It is striking that such a simple manipulation so clearly affects brain activity and behaviour. A simple modification of existing treatments could possibly improve effects. This would mean more people getting rid of their anxieties after treatment and fewer relapses,' says Johannes Björkstrand, PhD student at the Department of Psychology, Uppsala University.

From Science Daily

More to rainbows than meets the eye

There's more to rainbows than meets the eye.

In-depth review charts the scientific understanding of rainbows and highlights the many practical applications of this fascinating interaction between light, liquid and gas.

There's more to rainbows than meets the eye. Knowledge gained from studying these multicoloured arcs of scattered light can be incredibly useful in ways that may not immediately spring to mind. Rainbow effects can warn of chemical contamination in the atmosphere, help to develop more efficient combustion engines and possibly even provide insight into the mechanics of reinforced concrete.

Writing in European Journal of Physics, Alexander Haußmann of the Institute of Applied Physics at the Technical University of Dresden, Germany, has reviewed the latest developments in the field of rainbow research. His article takes a comprehensive look at natural rainbows and touches on the many practical applications of this fascinating interaction between light, liquid and gas.

Haußmann has been studying rainbows for more than 20 years. His interest began at school where he and his friends would log meteorological data for fun to keep tabs on changes in the weather. Today, weather watching has become more sophisticated with the introduction of techniques such as radar remote sensing, but observing rainbows remains important. As Haußmann points out, these patterns of scattered light can provide considerable clues to the size distribution and shape of raindrops falling during wet weather. If paired with radar data, this information could be used to quantify the amount of rainwater reaching the ground. "If our analysis methods are precise enough, we can turn rainbows into optical remote sensing tools to study the physics of rain," he comments.

Haußmann's review delves deep into the challenges of simulating rainbows as mathematical modeling is an important tool in furthering our understanding of this field. There are some key points that add to the puzzle. "Rain drops are not exactly spherical, but become deformed into slightly flattened 'hamburger bun' shapes due to air drag as they fall through the sky," he explained. "This has a drastic influence on the appearance of rainbows and makes scattering calculations numerically very demanding."

As well as focusing on the science, the article also provides tips for capturing rainbows on camera, which could help to win bragging rights on Instagram and other popular photo-sharing websites. "Rainbows are short-lived and special phenomena such as twinned bows are pretty rare, so it's important to always have your camera to hand," recommends Haußmann. "This can be a smartphone or, in my case, an SLR camera with a fisheye lens to capture the full width of a rainbow in a single frame."

From Science Daily

Unexpected trove of gas discovered around larger stars

Artist impression of a debris disk surrounding a star in the Scorpius-Centaurus Association. ALMA discovered that -- contrary to expectations -- the more massive stars in this region retain considerable stores of carbon monoxide gas. This finding could offer new insights into the timeline for giant planet formation around young stars.

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) surveyed dozens of young stars -- some Sun-like and others approximately double that size -- and discovered that the larger variety have surprisingly rich reservoirs of carbon monoxide gas in their debris disks. In contrast, the lower-mass, Sun-like stars have debris disks that are virtually gas-free.

This finding runs counter to astronomers' expectations, which hold that stronger radiation from larger stars should strip away gas from their debris disks faster than the comparatively mild radiation from smaller stars. It may also offer new insights into the timeline for giant planet formation around young stars.

Debris disks are found around stars that have shed their dusty, gas-filled protoplanetary disks and gone on to form planets, asteroids, comets, and other planetesimals. Around younger stars, however, many of these newly formed objects have yet to settle into stately orbits and routinely collide, producing enough rubble to spawn a "second-generation" disk of debris.

"Previous spectroscopic measurements of debris disks revealed that certain ones had an unexpected chemical signature suggesting they had an overabundance of carbon monoxide gas," said Jesse Lieman-Sifry, lead author on a paper published in Astrophysical Journal. At the time of the observations, Lieman-Sifry was an undergraduate astronomy major at Wesleyan University in Middletown, Connecticut. "This discovery was puzzling since astronomers believe that this gas should be long gone by the time we see evidence of a debris disk," he said.

In search of clues as to why certain stars harbor gas-rich disks, Lieman-Sifry and his team surveyed 24 star systems in the Scorpius-Centaurus Association. This loose stellar agglomeration, which lies a few hundred light-years from Earth, contains hundreds of low- and intermediate-mass stars. For reference, astronomers consider our Sun to be a low-mass star.

The astronomers narrowed their search to stars between five and ten million years old -- old enough to host full-fledged planetary systems and debris disks -- and used ALMA to examine the millimeter-wavelength "glow" from the carbon monoxide in the stars' debris disks.

The team carried out their survey over a total of six nights between December 2013 and December 2014, observing for a mere ten minutes each night. At the time it was conducted, this study constituted the most extensive millimeter-wavelength interferometric survey of stellar debris disks ever achieved.

Armed with an incredibly rich set of observations, the astronomers found the most gas-rich disks ever recorded in a single study. Among their sample of two dozen disks, the researchers spotted three that exhibited strong carbon monoxide emission. Much to their surprise, all three gas-rich disks surrounded stars about twice as massive as the Sun. None of the 16 smaller, Sun-like stars in the sample appeared to have disks with large stores of carbon monoxide.

This finding is counterintuitive because higher-mass stars flood their planetary systems with energetic ultraviolet radiation that should destroy the carbon monoxide gas lingering in their debris disks. This new research reveals, however, that the larger stars are somehow able to either preserve or replenish their carbon monoxide stockpiles.

"We're not sure whether these stars are holding onto reservoirs of gas much longer than expected, or whether there's a sort of 'last gasp' of second-generation gas produced by collisions of comets or evaporation from the icy mantles of dust grains," said Meredith Hughes, an astronomer at Wesleyan University and coauthor of the study.

The existence of this gas may have important implications for planet formation, says Hughes. Carbon monoxide is a major constituent of the atmospheres of giant planets. Its presence in debris disks could mean that other gases, including hydrogen, are present, but perhaps in much lower concentrations. If certain debris disks are able to hold onto appreciable amounts of gas, it might push back astronomers' expected deadline for giant planet formation around young stars, the astronomers speculate.

"Future high-resolution observations of these gas-rich systems may allow astronomers to infer the location of the gas within the disk, which may shed light on the origin of the gas," says co-author Antonio Hales, an astronomer with the Joint ALMA Observatory in Santiago, Chile, and the National Radio Astronomy Observatory in Charlottesville, Virginia. "For instance, if the gas was produced by planetesimal collisions, it should be more highly concentrated in regions of the disk where those impacts occurred. ALMA is the only instrument capable of making these kind of high-resolution images."

Read more at Science Daily

A mammoth undertaking: Can de-extinction be ecologically responsible?

UCSB graduate student Molly Hardesty-Moore and ecologist Douglas McCauley.

Can the woolly mammoth be brought back from the dead? Scientists say it's only a matter of time.

In fact this year, the International Union for Conservation of Nature issued its first official set of guidelines on resurrecting extinct species. What's more, university research labs and non-governmental agencies have projects in motion to bring back extinct species. But is all of this a good idea?

A new paper by UC Santa Barbara researchers explores de-extinction -- the process of resurrecting an extinct species -- as a potential win for conservation and suggests how to make it so.

In an analysis in the journal Functional Ecology, UCSB ecologist Douglas McCauley and colleagues recommend several ways in which the science of de-extinction would have to evolve in order to make it maximally benefit ecological communities and ecosystems.

"The idea of de-extinction raises a fundamental and philosophical question: Are we doing it to create a zoo or recreate nature?" said co-author Benjamin Halpern, director of UCSB's National Center for Ecological Analysis and Synthesis. "Both are reasonable answers, but restoring species to a natural state will be a much, much harder endeavor. We offer guidelines for how to make ecological de-extinction more successful and how to avoid creating 'eco-zombies.' "

Bringing back species useful for conservation requires big-picture thinking. For example, the grassland ecosystem in which the mammoth once lived looks totally different today. For a variety of reasons -- human population expansion among them -- some areas where these creatures once roamed cannot be restored to their former ecology.

"What some are proposing to do with de-extinction will be like manufacturing a part from the engine of a Model T and trying to shove it into a Tesla," said lead author McCauley, an assistant professor in UCSB's Department of Ecology, Evolution and Marine Biology. "You just can't take a part and put it into a brand new system and expect it to work without considering how its ecological context has changed.

"Good conservation is a holistic science that acknowledges the fact that many species interact in complex ways," McCauley added. "The rules in that complex web of life don't stay static but evolve dynamically."

The UCSB team developed three recommendations for restoring ecological function through de-extinction. The first suggests resurrecting recently extinct species rather than those that disappeared thousands of years ago. These creatures may fit more seamlessly into their ecosystems because there has been less time for change to occur. The researchers offer several examples of these "young" extinctions, including the Christmas Island pipistrelle bat, the Réunion giant tortoise and Australia's lesser stick-nest rat.

Secondly, the group advises choosing animals whose ecological jobs are truly irreplaceable. For example, the Christmas Island pipistrelle bat was once the only insect-eating bat in its habitat. Its de-extinction would plug a hole in an ecosystem that nature would otherwise have a hard time filling.

Ditto for the Réunion giant tortoise, which dispersed seeds throughout its Indian Ocean island habitat before being driven extinct by hungry mariners. Those plants still exist, although they are moving closer to extinction without the tortoises to perform their ecological function as seed distributors.

The third guideline, according to co-author Molly Hardesty-Moore, a graduate student in McCauley's lab, is to bring back species that can be restored to functionally meaningful abundance levels. "You need to have enough individuals to perform their function well enough to affect the ecosystem," she said. "One wolf hunting and killing has minimal impact, but hundreds of wolves performing that function will change the ecosystem."

Read more at Science Daily

300 Teeth: Duck-billed dinosaurs would have been dentist’s dream

Tethyshadros insularis, a hadrosaur. Duck-billed dinosaurs (hadrosaurs), who lived in the Cretaceous period between 90 million and 65 million years ago, sported this unique dental system, which had never been fully understood until it was examined at the microscopic level

Imagine how much dental care you'd need if you had 300 or more teeth packed together on each side of your mouth.

Duck-billed dinosaurs (hadrosaurs), who lived in the Cretaceous period between 90 million and 65 million years ago, sported this unique dental system, which had never been fully understood until it was examined at the microscopic level through recent research conducted by Aaron LeBlanc, a University of Toronto Mississauga PhD candidate; his supervisor, Professor Robert Reisz, the University of Toronto Mississauga vice-dean, graduate, and colleagues at the Royal Ontario Museum and the Museum of the Rockies.

Rather than shedding teeth and replacing them with new ones like other reptiles, hadrosaurs' mouths contain several parallel stacks of six or more teeth apiece, forming a "highly dynamic network" of teeth that was used to grind and shear tough plant material. Although hadrosaur teeth appear to be fused in place, LeBlanc and his colleagues show that the newest teeth were constantly pushed towards the chewing surface by a complex set of ligaments. When viewed under the microscope, the columns of teeth are not physically touching and are held together by the sand and mud that can get in between the teeth following the decay of the soft ligaments after the animals died.

"Hadrosaur teeth are actually similar to what we have because our teeth are not solidly attached to our jaws. Like us, hadrosaur teeth would have had some fine-scale mobility as they chewed thanks to this ligament system that suspended the teeth in place," says Reisz.

As they reached the grinding surface, hadrosaur teeth were essentially dead, filled with hard tissue -- unlike humans, whose teeth have an inner core filled with blood vessels and nerves.

"Since the teeth were already dead, they could be ground down to little nubbins," Reisz says.

LeBlanc says this tooth structure -- with its tough grinding surface -- was "well-adapted to break down tough plant material for digestion," through both shearing and grinding. This adaptation may have contributed to the hadrosaurs' longevity and proliferation.

Reisz says that hadrosaurs had "probably the most complex dental system ever made."

"It's very elegant -- not a single brick of teeth working as a solid unit," he says. "It's more like chain mail, providing flexibility as well as strength."

LeBlanc notes that the duck-billed dinosaur has been known for over 150 years and its dental system has long been recognized as unique, but no one had taken a look inside it at the microscopic level previously. He created thin sections of entire dental assemblies from the upper and lower jaws, that he then ground down, polished and examined under a powerful microscope. Working with their museum colleagues, he and Reisz were also able to explore how hadrosaur teeth form in embryos and hatchlings, providing a more complete picture of this unique model of dental evolution and development.

Read more at Science Daily

Etruscan Inscription Reveals Name of Goddess

The name of a powerful goddess of fertility has emerged from a 2,500-year-old inscribed slab, revealing what might be the longest Etruscan inscription on stone.

Written in the puzzling Etruscan language, the stone bears the name of Uni, the supreme goddess of the Etruscan pantheon -- basically the equivalent to the Greek goddess Hera and the Roman Juno.

Weighing about 500 pounds and nearly four feet tall by two feet wide, the sandstone slab, or stele, was discovered some months ago during the final stages of two decades of digging at Poggio Colla, some 22 miles miles north-east of Florence in the Mugello Valley.

It was found embedded in the foundations of a stone temple.

The 6th century B.C. slab is heavily abraded and chipped and contains text, written right to left, of more than 120 characters. It is divided into words by means of three vertically aligned dots.

"Cleaning at a restoration center in Florence has allowed better visibility of the inscribed signs, making it possible to identify a larger sequence of letters and words," Adriano Maggiani, a former professor at the University of Venice and one of the scholars working to decipher the inscription, told Discovery News.

"The presence in the inscription of the name Uni suggests the text has a religious character," he added.

Maggiani also identified the name Tinia, the Etruscan supreme deity, equivalent to ancient Greece's Zeus or Rome's Jupiter.

However, it appears the sanctuary was dedicated only to Uni, Tinia's female consort.

"It is my understanding that the structure of the line that includes both names has bearing on the matter," archaeologist Gregory Warden, professor emeritus at Southern Methodist University, Dallas, and co-director of the Mugello Valley Archaeological Project, told Discovery News.

He stressed that this is a preliminary reading and further research is necessary.

"Etruscan sanctuaries are often dedicated to more than one deity. And we have possible indications that the cult may have changed in nature. As always, you answer one question but raise many more," Warden added.

Indications that Uni was worshipped at the site comes from the location of the stone's discovery.

"The center of worship was an underground fissure that was ritually treated after the destruction of the temple," Warden said.

The ritual included placing a temple block in front of the fissure, along with a gold ring and a textile embroidered with gold.

"Underground cults of this type were often associated with female divinities," Warden said.

The abundance of weaving tools and a stunning deposit of gold jewelry discovered in previous excavations, already implied that the patron divinity was female. Four years ago, a unique scene of a goddess giving birth was found on a small fragment from a ceramic vessel.

It was the earliest scene of childbirth in western European art and again pointed to an Etruscan fertility goddess.

Recognizing beyond doubt the deity to which the sanctuary was dedicated would be a unique discovery as very few Etruscan sanctuaries can be conclusively identified.

Considered one of the most religious cultures of the ancient world, the Etruscans began to flourish around 900 B.C., and dominated much of Italy for five centuries.

Known for their art, agriculture, fine metalworking and commerce, they became absorbed into the Roman empire by 300-100 B.C.

Read more at Discovery News

Arctic gives clues on worst mass extinction of life

After an extreme global warming 252 million years ago, a severe mass extinction of life took place on Earth. A new study in the Arctic has been seeking clues as to what limited return of life to world´s oceans after this event.

Extreme global warming 252 million years ago caused a severe mass extinction of life on Earth. It took life up to 9 million years to recover. New study finds clues in the Arctic as to why this recovery took so long.

96 percent of marine species, and 70 percent of terrestrial life died off in the Permian-Triassic extinction event, as geologists know it. It is also known as The Great Dying Event for obvious reasons.

"The mass extinction was likely triggered by a explosive event of volcanic eruptions in what is now Siberia. These eruptions lasted for a million years and emitted enormous amounts of volatiles, such as carbon dioxide and methane, which made our planet unbearably hot." says Jochen Knies, researcher at Centre for Arctic Gas Hydrate, Environment and Climate at UiT The Arctic University of Tromsø.

Life took an extraordinary amount of time to recover from this extinction, from 5 to 9 million years. Why recovery was so delayed, has remained a mystery.

Clues are in the Arctic

Knies is the co-author of a study in Geology that took to the Arctic to look for clues as to what limited return of life to world´s oceans. The results of the study illustrate potential long-term impacts on marine ecosystems in response to global warming.

"What used to be the northwestern continental margin of the supercontinent Pangaea is now Canadian High Arctic. There we found evidence in geological records for a significant nutrient gap during this period. This means that global oceans were severely poor in nutrients such as nitrogen," says Knies.

This nutrient gap is most likely the result of extremely high ocean surface temperatures in the aftermath of the extinction.

Be cool -- stay alive

Our oceans are not a single body of water. They are comprised of layers and boundaries based on temperature (thermocline) and nutrients (nutricline) among others.

"The high temperatures caused deepening of the thermocline and nutricline in the ocean so that upwelling of nutrients from the bottom to the surface of ocean ceased. With that the marine algae productivity was stalled," according to Knies.

And without algae, which are the base of the food chain, the life in the ocean did not thrive.

Once oceans finally started cooling 6-7 million years after the extinction, nutrient rich waters returned.

"The boundaries that kept the nutrients from reaching the surface were weakened and the ocean waters were mixed. This caused the upwelling of nutrients, resuscitating the oceans, and leading to an explosion of life. The ecosystem voids created by the worst mass extinction in Earth history were finally filled." states Jochen Knies.

Read more at Science Daily

Humans Have Caused Climate Change For 180 Years

Humans have been changing Earth's climate for 180 years, earlier than scientists had previously believed, a new study reports.

The research, published in the journal Nature, involved 25 scientists from Australia, the United States, Europe and Asia, working together as part of the Past Global Changes 2000 Year (PAGES 2K) Consortium. Lead author Nerilie Abram, an associate professor at Australian National University, and colleagues examined detailed climate reconstructions spanning the past 500 years to determine when the current warming trend truly began, and analyzed thousands of years of climate models to confirm its cause.

After poring through climate histories preserved in the likes of corals, cave decorations, tree rings and ice cores, Abram and her team established that the first signals of climate change could be observed as early as the 1830s.

That industrial age is generally considered to have begun in Britain in the mid-to-late 1700s; the development of mass production transformed the country and ultimately the world, but the use of coal to power the steam engines and factories that made it possible released carbon dioxide, a greenhouse gas, levels of which have been increasing in the atmosphere ever since. During ice ages, CO2 levels were around 200 parts per million (ppm), and prior to the Industrial Revolution, they were around 280 ppm; in 2013, CO2 levels surpassed 400 ppm.

Interestingly, the study found that warming's footprints spread gradually across the globe. The Arctic began warming first, and continues to show the greatest extent of warming on the planet. Tropical oceans show signs of climate change at around the same time, followed in short order by Europe, Asia and North America, with sustained warming beginning about 50 years later in Australasia and South America. There are localized variations within such regional changes, however: Sea surface temperature in the eastern tropical Pacific may have undergone sustained warming "markedly later" than other tropical ocean regions.

The authors note that the point at which they say warming began was immediately preceded by some cooling in the tropical oceans and over Northern Hemisphere landmasses, largely caused by increased volcanic activity, such as the 1815 Tambora eruption. However, their reconstructions found that, even after accounting for a recovery from such conditions, the evidence was unambiguous: even the relatively small amount of greenhouse gases that had been released to that point were enough to stimulate warming.

"It was an extraordinary finding," said Abram. "It was one of those moments where science really surprised us. But the results were clear. The climate warming we are witnessing today started about 180 years ago."

From Discovery News

Rare Endangered Primate Spotted in Vietnam

A new group of critically endangered primates has been spotted in Vietnam, raising hopes the rare creatures may not be wiped out in the next decade as scientists had feared.

The Delacour's langur, black and white with a full face of whiskers, is indigenous to Vietnam, but their numbers have dwindled in recent years because of poaching and mining activity in the country's northern forests.

A team of scientists from Fauna and Flora International spotted a group of about 40 of the primates, mostly juveniles and infants, bringing their total population to less than 250.

"It's great news for this particular species because had we not found this new population, they were in grave danger of being wiped out within a decade," spokeswoman for FFI in Vietnam, Akofa Wallace, told AFP Tuesday.

"The fact that they are breeding is brilliant news," she added.

FFI did not say where scientists spotted the langurs, whose habitat is threatened by mining activity in the area, including charcoal production.

They are also targeted by poachers who hunt them for meat, with their bones used for traditional medicine and their pelts for decoration.

The primate was discovered in northern Vietnam in the 1930s by French scientist Jean Theodore Delacour, and are only found in Vietnam.

FFI country director Benjamin Rawson said urgent interventions were needed to protect the species, which numbered about 300 in the early 1990s.

"We continue to work alongside officials and local communities to ensure the Delacour's langur doesn't become this century's first primate extinction," Rawson said in a statement.

Read more at Discovery News

NASA Regains Contact With 'Dead' Solar Mission

NASA has finally re-established contact with a sun-watching probe that was thought to be lost in space after it abruptly went silent in 2014.

A signal from the long-lost spacecraft, called STEREO-B, was detected Sunday evening (Aug. 21) by NASA's Deep Space Network, a collection of space tracking stations that follows the agency's space missions across the solar system and beyond. NASA scientists had kept vigil for STEREO-B, making monthly searches for the probe until it phoned home Sunday at 6:57 p.m. EDT (2257 GMT).

Right now, it's unclear how healthy the spacecraft is after drifting in space for nearly two years. NASA lost contact with it on Oct. 1, 2014, after commanding a reset from Earth. The spacecraft's twin, STEREO-A, is still working normally.

"The STEREO Missions Operations team plans further recovery processes to assess observatory health, re-establish attitude control, and evaluate all subsystems and instruments," NASA officials wrote in a statement.

The STEREO spacecraft twins (their name is short for Solar and Terrestrial Relations Observatory) were launched in October 2006 and were originally supposed to last until 2008. With an extended mission, however, came challenges. For example, the orbits of both STEREO spacecraft went behind the sun in 2015, for three months each.

 STEREO-B was initially lost when NASA was testing a command loss timer, which is a reset triggered during solar conjunction. Conjunction was expected to happen between January and March 2015, when STEREO-B's orbit took it behind the sun, putting it out of contact with Earth.Both STEREO spacecraft have a command loss timer that resets the spacecraft every 72 hours when it is not communicating with Earth. In 2014, controllers deliberately stopped communicating with STEREO-A to test this process, and it worked perfectly after reorienting itself with respect to certain guide stars, and sending a signal to Earth.

With STEREO-B, however, the test did not play out as planned. The hard reset did occur, and STEREO-B sent a weak signal to Earth. But the spacecraft quickly faded into silence.

Only a few packets of data made it to Earth, but from that, the team concluded in December 2015 that the inertial measurement unit (which tells the spacecraft if it is rotating, and how fast) gave incorrect information into STEREO-B's guidance computer. At the time, NASA concluded that this set the spacecraft into a spin that left its solar panels out of sunlight most of the time, making it difficult to recharge the battery.

Read more at Discovery News