Deepest Ocean Water Teems With Life

A few years ago, film director James Cameron spent hours scouring the world’s deepest ocean canyon for any sign of life. He found a few bizarre animals, but it turns out the real action in the Mariana Trench happens beyond the reach of a submersible’s camera.

Researchers from Japan discovered microscopic bacteria thrive in the canyon called Challenger Deep, which is the lowest point on Earth’s surface and the deepest part of the Mariana Trench, the team reports today (Feb. 23) in the journal Proceedings of the National Academy of Sciences. In particular, they found an unusual community of bacteria there called heterotrophs, or microbes that cannot produce their own food and must eat what they find in the water.

Cameron found that larger life forms were scarce compared to shallow ocean waters. However, the heterotrophic life in Challenger Deep’s waters was relatively abundant, similar to that in untreated well water, said lead study author Takuro Nunoura, a microbiologist with the Japan Agency for Marine-Earth Science and Technology (JAMSTEC).

The average depth of the ocean floor is about 13,120 feet (4,000 meters); its deepest point is in the western Pacific’s Mariana Trench, where the Challenger Deep canyon bottoms out at more than 36,000 feet (nearly 11,000 m) below sea level. All kinds of microscopic life are found in the seafloor at this depth, from bacteria and archaea to yeast and viruses, according to this and other studies.

The heterotrophs in the Challenger Deep likely derive food from sinking particles, such as dissolved fecal pellets or dust, or possibly from geologic processes such as earthquake-triggered landslides, which could send organic-rich sediments tumbling into the canyon’s depths, the researchers said.

“These big slope collapses are rare accidents in terms of human life spans, but they happen very frequently on a geologic timescale, and the release of organic compounds could continue for a very long time,” Nunoura told Live Science.

Recent studies in the Challenger Deep by a separate team also reported that the sediments there host more microbes than the nearby vast, deep ocean floor — called the abyssal plains.

The research team measured the abundance of life and the temperature, salinity and chemistry of seawater from the surface waters above the Mariana Trench to the bottom of the Challenger Deep with a remotely operated vehicle. They found the ocean’s microbial diversity varied with depth. Genetic-fingerprinting techniques identified different microbes based on certain genes, and also indicated the relative abundance of different species.

The ocean’s invisible life was found at all depths, but microbes were most abundant near the surface and on the ocean floor, where they can find the most food. The ocean was stratified into layers, with a warm, salty layer on top and a colder, less salty layer starting about 1,300 feet (400 m) below the surface. The deepest water was about 1 degree Celsius (34 degrees Fahrenheit).

Read more at Discovery News

Using Jupiter as an Alien World Analog

Owing to its size, fascinating chemistry and system of varied moons, Jupiter is one of the most studied planets in the solar system, though many mysteries remain. But a new study has taken a look at the gas giant from a whole different perspective — as an alien, living far beyond the solar system, would see it.

At first it may not seem obvious what a team of astrophysicists at the Astrophysics Institute of the Canary Islands in Tenerife are doing. As Jupiter passed between the sun and its largest moon Ganymede, the researchers, headed by Pilar Montañés-Rodríguez, studied the faint light reflecting off the moon’s surface.

When Jupiter blocks the sunlight from Ganymede’s perspective, some of that sunlight is filtered and scattered through the gas giant’s atmosphere. This scattered light therefore carries some information about what Jupiter’s atmosphere contains.

Now, if we were an alien in a neighboring star system and we saw Jupiter pass in front of the sun, we might want to zoom in on Jupiter to measure the scattered light so we can understand what Jupiter is made of. But from Earth’s perspective, Jupiter never passes between us and the sun, so we can never hope to study the scattered light passing through Jupiter’s upper atmosphere. (Indeed, the only planet with an atmosphere that passes between the sun and Earth is Venus, but the next Venus transit doesn’t occur until the year 2125.)

This is where Ganymede comes in.

During partial eclipse events, as Jupiter blocks sunlight from directly hitting Ganeymede, Montañés-Rodríguez’s team zoomed in on the moon and detected the very faint reflected light that had already passed through Jupiter’s atmosphere and bounced off Ganymede. They are basically using Ganymede as a reflector, allowing us a view of Jupiter we wouldn’t otherwise have ever seen.

Using the European Southern Observatory’s Very Large Telescope (VLT) in Paranal, Chile, and the William Herschel Telescope at the La Palma Observatory in Spain’s Canary Islands, the researchers were able to tease-out valuable spectroscopic information from this reflected light, building a picture of Jupiter’s atmospheric composition. And even though Jupiter may be pretty well studied, the team made an unexpected discovery about the solar system’s largest world.

Within the spectroscopic data appears to be some evidence of water ice, a factor that may prove controversial, says Montañés-Rodríguez, as Jupiter is thought to contain very little water. Perhaps this discovery suggests that cometary impacts on Jupiter deposited a layer of water ice that has, until now, evaded detection.

But key to this research is to use Jupiter as an analog exoplanet. As we know — more or less — what the planet is made of, its chemical composition and atmospheric stratification, the researchers hope to use the reflected light from Ganymede during Jovian eclipse events to build a profile of what information the scattered sunlight through a massive planet’s atmosphere contains. By comparing the Jupiter data with exoplanet transit events, we can better understand the signal of refracted and scattered starlight through these alien worlds’ atmospheres.

“It’s an extremely clever idea and spectacularly carried out,” said astronomer Sara Seager, of the Massachusetts Institute of Technology in Cambridge.

Read more at Discovery News

Octopus Nabs Crab on Land in Striking Footage

As the saying goes, in life sometimes you're the octopus and sometimes you're the crab. OK, so that's not a terribly common saying -- perhaps instead we could say that sometimes you're shooting video of a crab and an octopus jumps out of the water to eat your subject.

That's what happened in Yallingup, western Australia to Porsche Indrisie. Ms. Indrisie was "randomly filming" a yellow crab in a rock pool, she wrote on her Youtube account, when a crafty octopus lurking just underneath the surface noticed the potential meal at the water's edge and sprang into action.

As seen in the footage below, the octopus pounces on the crab unawares -- steering clear of the crab's claws -- and then drags it backward across the rocks and into the water, where the shell-shocked crustacean doubtless becomes lunch for the multi-armed predator.

How soft octopi kill hard crabs, a regular feature of their diet, is fascinating and grisly. As displayed in this video from Howstuffworks, an octopus first reels in a crab with its suckered arms. Then it bites the crab with its beak, paralyzes it with venom, and gorges on the unlucky creature's innards. All that's left after the meal is an empty shell that used to have a crab in it.

Sometimes, in life, you're the crab that should have been more careful.

Read more at Discovery News

Mysterious, Wavelike Cloud Hugs Grand Tetons

A bizarre sheet of clouds embraced the highest peak in Grand Teton National Park in Wyoming last week, enchanting even the park's most seasoned visitors.

The clouds looked like a billowing handkerchief or an ocean’s wave crashing into the mountain. The clouds were so strange they even surprised park spokeswoman Jackie Skaggs.

"I've lived here for almost 40 years, and honestly, I've never seen something last that long and take so many different shapes," Skaggs told Live Science.

Skaggs first spotted the clouds on her morning drive to work. "I watched it the whole drive up and then stood there for about 20 minutes before coming into the building because I couldn't leave it," Skaggs said.

In the late morning, Skaggs was once again pulled from work to watch the majestic clouds. But this time, she grabbed a camera and snapped the above photo of their unique shape. The clouds finally dissipated in the afternoon, she said.

Chris Jones, a meteorologist with the National Weather Service, thinks the formations are lenticular clouds. These clouds form when waves of moist, fast-moving air run into the surface of a mountain. The mountain’s jagged topography forces the air upward, which cools and condenses the air, transforming it into a cloud.

They can look like one large, lens-shaped cloud (often mistaken for a UFO); stacks of pancakes atop one another; or an undulating wave, like the one last week.

"These mountains definitely have a magical, spiritual aura about them,” Skaggs said. Their jagged peaks rise as high as 13,775 feet (4,200 meters) above sea level. But without any foothills to obstruct the view, they stand mighty and tall. The Teton Range is part of the Rocky Mountains, which stretch more than 3,000 miles (4,800 kilometers) across western North America, from British Columbia, Canada, to New Mexico.

From Discovery News

Dolphins Swam into Mediterranean 18,000 Years Ago

Bottlenose dolphins moved into the Mediterranean, once too salty to harbor much marine life, at the end of the last ice age about 18,000 years ago, a new study finds.

"It is quite likely that the bottlenose dolphin hasn't actually been in the Mediterranean for long, in terms of the evolutionary time frame," said Andre Moura, one of the study's researchers and a lecturer of life science at the University of Lincoln in the United Kingdom.

During the last ice age, the Mediterranean was saltier and shallower than it is today, making it a difficult place for marine creatures to live, the researchers said. Even if bottlenose dolphins living in the Atlantic Ocean had ventured into the Mediterranean during that time, they would have been hard-pressed to find food that could survive in such a salty environment.

"Bottlenose are mammals; they're very big," Moura told Live Science. "They need a lot of food to survive and do well."

As glaciers from the last ice age melted into the Mediterranean, the sea became less salty. When fish and other sea creatures moved in, hungry bottlenose dolphins quickly followed, Moura said.

But Moura and his colleagues wanted to learn more than the dolphins' Mediterranean arrival date. Bottlenose dolphins in the eastern Mediterranean Sea, especially in the Adriatic Sea next to Italy, are often killed as bycatch by the fishery industry, said Stefania Gaspari, the study's lead author and a researcher of population genetics at the University of Florence.

"It is crucial to know if, for example, the Adriatic Sea is populated by a single population of bottlenose dolphins or by more than one population," Gaspari told Live Science in an email.

If the Mediterranean has multiple dolphin groups, then it could lose some of its genetic diversity, a large detriment, if a group of dolphins were to die in a region such as the Adriatic Sea, she said.

To investigate, the researchers analyzed tissue samples containing DNA and mitochondrial DNA (genetic material inherited from mothers) from 194 adult bottlenose dolphins (Tursiops truncatus).

They compared their results with data on North Atlantic bottlenose dolphins from previous studies. All of the dolphins were related: The bottlenose dolphins in the North Atlantic, Mediterranean and North Sea likely represent a single metapopulation, a large population of animals with regional subgroups that interbreed, the analysis showed.

Each subpopulation preferred a specific area, such as deep open water or a stretch of shallow coastal water. Dolphins that live in deep water are more likely to join coastal populations if the area supports more dolphins, Moura said.

But this source of new dolphins has a limit, he said: If a subpopulation on the coast goes extinct, then the deep-water dolphins will likely try to recolonize the area. Whatever led to the demise of the first subpopulation — overfishing or pollution, for example — may also harm the new colonizers, Moura noted.

For this reason, conservation efforts should focus more on the environment than on the dolphin itself, Moura said.

Read more at Discovery News

Mummified Monk Sits Inside Ancient Buddha Statue

Researchers at the Drents Museum in the Netherlands made a shocking discovery when they imaged an ancient Chinese statue and found a nearly 1,000-year-old mummy inside.

Sitting in the lotus position, the mummy fits within the statue perfectly.

"On the outside, it looks like a large statue of Buddha," the museum said in a release. "Scan research has shown that on the inside, it is the mummy of a Buddhist monk who lived around the year 1100."

Glowing through the statue's golden cast, the human skeleton is believed to belong to Buddhist master Liu Quan, a member of the Chinese Meditation School.

To further investigate the mummy, the researchers took the statue to the Meander Medical Center in Amersfoort and carried out an endoscopy and additional CT scans.

They found out that Liu Quan's internal organs had been removed and replaced with scripts covered in Chinese writing.

The museum speculates Liu Quan may have "self-mummified" in order to become a "living Buddha."

Practiced mainly in Japan, self-mummification was a grueling process that required a monk to follow a strict 1,000-day diet of nuts and seeds in order to strip the body of fat. A diet of bark and roots would follow for another 1,000 days.

At the end of this period, the monk began drinking a poisonous tea made from the sap of the Japanese varnish tree, normally used to lacquer bowls and plates. The tea caused profuse vomiting as well as a rapid loss of bodily fluids, possibly making the body too poisonous to be eaten by bacteria and insects.

A living skeleton, the monk was then placed in a stone tomb barely larger than his body, which was equipped with an air tube and a bell.

Never moving from the lotus position, the monk would ring the bell each day to let those outside know that he was still alive. When the bell stopped ringing, the monk was presumed dead, the air tube removed and the tomb sealed.

After another 1,000 days the tomb would be opened to check whether the monk had been successfully mummified. Of the hundreds of monks that tried this horrifying process, only a few dozen actually became self-mummified and venerated in temples as a Buddha.

Read more at Discovery News

Star Quadruplets Spied Growing Inside Stellar Womb

New observations of a star-forming nebula have revealed four stellar embryos, providing clues as to how multiple star systems evolve.

The majority of stars in our galaxy come in pairs, triplets or even quadruplets, but our sun appears to be a loner. This fact poses an interesting question: if our star is alone, and yet contains a rich multiplanetary system, how do planetary systems evolve in multi-star systems?

In a new study published in the journal Nature this week, Alyssa Goodman, professor of astronomy at the Harvard-Smithsonian Center for Astrophysics (CfA), reports on the discovery of four embryonic stars slowly forming 825 light-years from Earth. Previously known to contain one protostar, the molecular cloud located in the constellation Perseus apparently contains more stellar siblings.

One of the biggest puzzles in understanding the evolution of multi-star systems is how they formed; did they spawn from the same stellar nursery as true fraternal twins would or did the stars come from different locations only to be gravitationally captured later in their lives? According to theoretical models both ideas are viable.

By studying the radio emissions from the molecular cloud, Goodman’s team discovered “several filamentary gas structures in which they detected three other concentrations,” writes a Smithsonian Astrophysical Observatory news release.

The researchers believe that these gas concentrations, which are two-to-three times more massive than the known protostar, are collapsing under mutual gravity. In other words, stellar quadruplets are coalescing and three of these newly-detected star embryos will likely undergo nuclear fusion in their cores, becoming baby stars, in roughly 40,000 years time. In cosmic timescales, this particular stellar womb is teetering on the edge of giving birth.

Most interesting is the scale of the region. The system measures only 10,000 astronomical units (AU) across — where 1 AU is the average distance between the Earth and sun. For scale, all four stellar embryos would fit easily within the boundaries of our solar system, where the outermost boundary is the Oort Cloud, a hypothetical region containing billions of cometary nuclei surrounding our sun. The inner Oort Cloud’s outermost boundary is 20,000 AU from the sun.

Their close proximity means that all four stars are gravitationally interacting and velocity measurements confirms this possibility.

Read more at Discovery News

What Black Hole Winds Tell You about Galaxies

This illustration shows gusts of charged particles streaming in all directions from a black hole at the center of a galaxy.

Black holes suck. Their gravitational pull is so powerful that black holes famously grab anything near them in space—even light. But black holes also, it turns out, blow. If they’re gobbling up any nearby matter, black holes actually stream charged subatomic particles. And that, astronomers now say, has huge consequences for the life of nearby stars and the shape of whole galaxies.

Supermassive black holes like the ones at the center of some galaxies are surrounded by gas and dust spiraling into the maw. As all that stuff gets pulled in, the pieces rub against each other. That friction becomes energy, radiation that turns the atoms of the dust-disc into charged particles. All that stuff then rushes outward at speeds approaching a third of the speed of light. “We’ve known for a while now that every galaxy like the Milky Way has a supermassive black hole at its heart, and we also know there’s a connection between the mass of the black hole and the mass of the galaxy,” says Fiona Harrison, an astronomer at Caltech who worked on the new research. “But it’s a mystery why. One hypothesis is that through blows like this, black holes can actually affect galaxies on large scales.”

That expanding bubble of ions packs a serious punch—like about 10 trillion suns’ worth. It blows away the random bits of gas and dust always hanging around a galactic core. But gas and dust are the raw materials for building new stars. Once it’s gone: No more new stars.

Harrison and her colleagues were looking at x-ray data from a black hole 2 billion light years away, in the heart of a quasar unpoetically called PDS 456. Earlier observations from a space telescope called XMM-Newton, in orbit between Earth and the moon, revealed the wind, but blowing more narrowly. Adding in data from a telescope in low-Earth orbit, NuSTAR, showed the wind blowing outward in every direction. The scientists had never seen that before. “We’re trying to tell the narrative story of galaxy formation,” says Roger Blandford, an astrophysicist at Stanford University. “We understand quite a lot of the physics, but it has to be guided by observations. This is a good measurement that will help along the way.”

From Wired Science

Newborn neurons in adult brain may help us adapt to environment

The discovery that the human brain continues to produce new neurons in adulthood challenged a major dogma in the field of neuroscience, but the role of these neurons in behavior and cognition is still not clear. In a review article published by Cell Press February 21st in Trends in Cognitive Sciences, Maya Opendak and Elizabeth Gould of Princeton University synthesize the vast literature on this topic, reviewing environmental factors that influence the birth of new neurons in the adult hippocampus, a region of the brain that plays an important role in memory and learning.

The authors discuss how the birth of such neurons may help animals and humans adapt to their current environment and circumstances in a complex and changing world. They advocate for testing these ideas using naturalistic designs, such as allowing laboratory rodents to live in more natural social burrow settings and observing how circumstances such as social status influence the rate at which new neurons are born.

"New neurons may serve as a means to fine-tune the hippocampus to the predicted environment," Opendak says. "In particular, seeking out rewarding experiences or avoiding stressful experiences may help each individual optimize his or her own brain. However, more naturalistic experimental conditions may be a necessary step toward understanding the adaptive significance of neurons born in the adult brain."

In recent years, it has become increasingly clear that environmental influences have a profound effect on the adult brain in a wide range of mammalian species. Stressful experiences, such as restraint, social defeat, exposure to predator odors, inescapable foot shock, and sleep deprivation, have been shown to decrease the number of new neurons in the hippocampus. By contrast, more rewarding experiences, such as physical exercise and mating, tend to increase the production of new neurons in the hippocampus.

The birth of new neurons in adulthood may have important behavioral and cognitive consequences. Stress-induced suppression of adult neurogenesis has been associated with impaired performance on hippocampus-dependent cognitive tasks, such as spatial navigation learning and object memory. Stressful experiences have also been shown to increase anxiety-like behaviors that are associated with the hippocampus. In contrast, rewarding experiences are associated with reduced anxiety-like behavior and improved performance on cognitive tasks involving the hippocampus.

Although scientists generally agree that our day-to-day actions change our brains even in adulthood, there is some disagreement on the adaptive significance of new neurons. For instance, the literature presents mixed findings on whether new neurons generated under a specific experimental condition are geared toward the recognition of that particular experience or if they provide a more naive pool of new neurons that enable environmental adaptation in the future.

Gould and her collaborators recently proposed that stress-induced decreases in new neuron formation might improve the chances of survival by increasing anxiety and inhibiting exploration, thereby prioritizing safety and avoidant behavior at the expense of performing optimally on cognitive tasks. On the other hand, reward-induced increases in new neuron number may reduce anxiety and facilitate exploration and learning, leading to greater reproductive success.

"Because the past is often the best predictor of the future, a stress-modeled brain may facilitate adaptive responses to life in a stressful environment, whereas a reward-modeled brain may do the same but for life in a low-stress, high-reward environment," says Gould, a professor of psychology and neuroscience at Princeton University.

However, when aversive experiences far outnumber rewarding ones in both quantity and intensity, the system may reach a breaking point and produce a maladaptive outcome. For example, repeated stress produces continued reduction in the birth of new neurons, and ultimately the emergence of heightened anxiety and depressive-like symptoms.

"Such a scenario could represent processes that are engaged under pathological conditions and may be somewhat akin to what humans experience when exposed to repeated traumatic stress," Opendak says.

Read more at Science Daily

The Hills Have Ice... on Mars, That Is

Scientists have been hunting for evidence of water on Mars ever since they started looking at the Red Planet through telescopes. But Mars does have water, and lots of it; solid water in the form of ice locked up in its polar caps and buried under its surface. And, if observations made by ESA’s Mars Express are indicative of similar processes seen on Earth, these ancient hills may also hide hidden deposits of ice.

The image above shows an oblique view of the southernmost tip of a long chain of hills in Mars’ northern hemisphere called Phlegra Montes, generated from data acquired by the High Resolution Stereo Camera aboard ESA’s Mars Express. The resolution is about 15 meters (50 feet) per pixel.

These rounded hills are thought to have once been covered by thick glaciers during a Martian ice age a few hundred million years ago. Like Earth, Mars’ rotational axis has a “wobble” that affects its global climate over long periods. While there are no glaciers in Mars’ mid-latitudes today, geologic evidence indicates there once were – and the shape of the surface around Phlegra Montes hints that there could still be ice just 20 meters underground.

Aprons of debris surrounding some of the hills resemble those found in glacial regions on Earth, where subsurface ice causes material to slump downhill.

The search for water on Mars is important to scientists who are trying to figure out how Mars may have gone from a warmer, wet world to the cold dry one we see today. Learning where the water has gone and how much of it is remains liquid or is now frozen solid is part of that process.

In addition, future long-term human exploration of Mars will rely on knowledge of where any potential sources of water might be found.

Launched aboard a Russian Soyuz/Fregat rocket on June 2, 2003, Mars Express has been in orbit at Mars since Dec. 25, 2003.

Read more at Discovery News