Oldest Hairy Microbe Fossils Discovered (weird science)

This microscopic fossil closely resembles a modern tintinnid, a single-celled organism that is a type of plankton. Fossil ciliates including this one were recently identified in a deposit in Mongolia, and they are more than 100 million years older than the previously known fossils of this type. Image credit: Tanja Bosak

This microscopic fossil closely resembles a modern tintinnid, a single-celled organism that is a type of plankton. Fossil ciliates including this one were recently identified in a deposit in Mongolia, and they are more than 100 million years older than the previously known fossils of this type.

Ancient rock deposits, laid down between two massive ice ages, reveal the oldest known fossils for two types of single-celled creatures: Tube-shelled foraminifera and hairy, vase-shape ciliates.

Both closely resemble microbes living today. But the climate they lived in may have been quite different. The fossils appear in limestone deposited on the ocean floor between 635 million and 715 million years ago. This period was marked by two "Snowball Earth" events, when ice may have covered the entire planet.

These fossils date back more than 100 million years earlier than the oldest foraminifera and ciliates previously known. Even so, scientists think these organisms were around much longer, based on changes accumulated in their DNA since they split from close relatives. Some believe these types of single-celled creatures have been around for considerably more than 1 billion years, said Tanja Bosak, a study researcher and assistant professor of geobiology at the Massachusetts Institute for Technology.

"We can't claim we have seen something that is exactly like the modern species," Bosak said. "(But) here we have something that has looked very similar for 700 or more million years."

The fossils have evaded researchers not only because they are so tiny, but also because these deposits do not contain a type of rock that typically preserves fossils, particularly something this small and fragile, she said.

Fossils belonging to foraminifera were found in rocks from Namibia, while ciliates were found in rocks from Mongolia. Both types first appear in layers of rock called cap carbonates, laid down as the world was leaving the earlier snowball state, which occurred 716 million years ago.

Foraminifera, ancient and modern, build protective shells by picking up tiny grains of mineral that they stick to their exterior using a sugary compound. They aren't the only shelled organisms Bosak and her colleagues found. They also discovered amoebas that appeared to be building the same sort of shells.

While this wasn't the first fossil evidence for these amoebas, the nature of their resistant covering was ambiguous in the earlier fossils. The most recent fossils are the first amoebas to show evidence of primitive shell building, Bosak said.

Ciliates, meanwhile, are covered with tiny hairs called cilia. And the fossils found closely resemble modern, planktonic organisms called tintinnids.

Life at the time was quite simple, but it soon became more complex. For instance, the first animal embryos show up after the end of the latest Snowball Earth event, around 635 million years ago.

It's possible the arrival of abundant microbes, particularly the ciliates, may have had some hand in the change, by helping to bump up the amount of oxygen in the atmosphere.

Even after free oxygen dramatically increased in the atmosphere, a change called the Great Oxidation Event, the oxygen level was much lower than it is today. The ciliates lived in the surface waters, then died and sank, taking organic carbon with them and tucking it away in sediments low in oxygen where the organisms would decompose only slowly. The burial of this carbon meant it could not be converted to carbon dioxide by respiration. As a result, oxygen produced by the photosynthesis of other microbes like algae would have built up.
The discovery of these organisms reveals a possible mechanism by which the oxygen levels in the atmosphere increased, allowing life to become more complex, she said.

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The research has been published in articles published online in October and November in the journal Geology, and online in June in the journal Earth and Planetary Science Letters.

| via LiveScience

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Water Doesn't Have to Freeze Until -55 F/ Study suggests

Regular ice crystals (red) are mixed with “intermediate ice” (green) near the end of the process of crystallizing from supercooled water. University of Utah chemists used computers to determine that water, which doesn’t necessarily become solid at its 32 degrees Fahrenheit freezing point, actually can get as cold as minus 55 F before it must freeze. (Credit: University of Utah)

University of Utah chemists may have solved one enigma by showing how cold water can get before it absolutely must freeze: 55 degrees below zero Fahrenheit.
That's 87 degrees Fahrenheit colder than what most people consider the freezing point of water, namely, 32 F.
Supercooled liquid water must become ice at minus 55 F not just because of the extreme cold, but because the molecular structure of water changes physically to form tetrahedron shapes, with each water molecule loosely bonded to four others, according to the new study by chemists Valeria Molinero and Emily Moore.

The findings suggest this structural change from liquid to "intermediate ice" explains the mystery of "what determines the temperature at which water is going to freeze," says Molinero, an assistant professor at the University of Utah and senior author of the study, published in the Nov. 24 issue of the journal Nature.
"This intermediate ice has a structure between the full structure of ice and the structure of the liquid," she adds. "We're solving a very old puzzle of what is going on in deeply supercooled water."

However, in the strange and wacky world of water, tiny amounts of liquid water theoretically still might be present even as temperatures plunge below minus 55 F and almost all the water has turned solid -- either into crystalline ice or amorphous water "glass," Molinero says. But any remaining liquid water can survive only an incredibly short time -- too short for the liquid's properties to be detected or measured.

How and at what temperature water must freeze has more than just "gee-whiz" appeal. Atmospheric scientists studying global warming want to know at what temperatures and rates water freezes and crystallizes into ice.
"You need that to predict how much water in the atmosphere is in the liquid state or crystal state," which relates to how much solar radiation is absorbed by atmospheric water and ice, Molinero says. "This is important for predictions of global climate."

A Strange Substance
Liquid water is a network of water molecules (each with two hydrogen atoms and one oxygen atom) held loosely together by what is called hydrogen bonding, which is somewhat like static cling. Molinero says that depending on its temperature and pressure, water ice has 16 different crystalline forms in which water molecules cling to each other with hydrogen bonds.

Molinero says that "what makes water so strange is that the way liquid water behaves is completely different from other liquids. For example, ice floats on water while most solids sink into their liquid forms because they are denser than the liquids."

Water's density changes with temperature, and it is most dense at 39 F. That's why fish survive under ice covering a pond by swimming in the warmer, denser water at the bottom of the pond.
But the property of water that "is most fascinating is that you can cool it down well below 32 degrees Fahrenheit and it still remains a liquid," says Molinero.

Liquid water as cold as minus 40 F has been found in clouds. Scientists have done experiments showing liquid water can exist at least down to minus 42 F.

Why doesn't water necessarily freeze at 32 F like we were taught in school?
"If you have liquid water and you want to form ice, then you have to first form a small nucleus or seed of ice from the liquid. The liquid has to give birth to ice," says Molinero. "For rain, you have to make liquid from vapor. Here, you have to make crystal [ice] from liquid."
Yet in very pure water, "the only way you can form a nucleus is by spontaneously changing the structure of the liquid," she adds.
Molinero says key questions include, "under which conditions do the nuclei form and are large enough to grow?" and "what is the size of this critical nucleus?"

Computing What Cannot Be Measured
Molinero says that "when you cool down water, its structure becomes closer to the structure of ice, which is why the density goes down, and this should be reflected in an increased crystallization rate."
Supercooled water has been measured down to about minus 42 F, which is its "homogenous nucleation temperature" -- the lowest temperature at which the ice crystallization rate can be measured as water is freezing. Below this temperature, ice is crystallizing too fast for any property of the remaining liquid to be measured.

To get around the problem, Molinero and chemistry doctoral student Moore used computers at the University of Utah's Center for High Performance Computing. The behavior of supercooled water was simulated and also modeled using real data.
Computers provide "a microscopic view through simulation that experiments cannot yet provide," Molinero says.

Previous computer simulations and modeling were too slow and had to last long enough for the freezing process to occur. And it was necessary to simulate thousands of nucleation events to make valid conclusions.
Molinero and Moore devised a new computer model that is 200 times faster than its predecessors. The model simplified the number crunching by considering each three-atom water molecule to be a single particle similar to a silicon atom and capable of sticking together with hydrogen bonding.

Even so, it took thousands of hours of computer time to simulate the behavior of 32,768 water molecules (much smaller than a tiny drop of water) to determine how the heat capacity, density and compressibility of water changes as it is supercooled, and to simulate how fast ice crystallized within a batch of 4,000 water molecules.

The Birth of Ice
The computers helped Molinero and Moore determine how cold water can get before it reaches its theoretical maximum crystallization rate and must freeze. The answer: minus 55 F (or minus 48 degrees Celsius).

The computers also showed that as water approaches minus 55 F, there is a sharp increase in the proportion of water molecules attached to four others to form tetrahedrons.
"The water is transforming to something else, and this something else is very close to ice," says Molinero. She calls it intermediate ice.

If a microscopic droplet of water is cooled very fast, it forms what is called a glass -- low-density amorphous ice -- in which all the tetrahedrons of water molecules are not lined up to form perfect crystals. Instead, low-density ice is amorphous like window glass. The study found that as many as one-quarter of the molecules in the amorphous "water glass" are organized either as intermediate ice or as tiny ice crystals.
When water approaches minus 55 F, there is an unusual decrease in density and unusual increases in heat capacity (which goes up instead of down) and compressibility (water gets easier to compress as it gets colder, unlike most liquids). These unusual thermodynamics coincide with liquid water changing to the tetrahedral structure.

"The change in structure of water controls the rate at which ice forms," Molinero says. "We show both the thermodynamics of water and the crystallization rate are controlled by the change in structure of liquid water that approaches the structure of ice."

(Via Science Daily)

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E. coli could convert sugar to biodiesel

Xingye Yu, a graduate student in chemical engineering, and Professor Chaitan Khosla examine a culture of e. coli bacteria.

When it comes to making biodiesel cheaply and efficiently enough to be commercially feasible, E. coli may prove to be "the little bacterial engine that could," say Stanford researchers.
Biodiesel can be made from plant oil or animal fat – usually the former. Used cooking oil from restaurants is common, but for biodiesel to contribute significantly to reducing fossil fuel use, there needs to be a way to mass produce it from plant-derived raw materials. The problem is that synthesizing biodiesel is complicated. That is where E. coli comes in.
The bacteria, often discussed in terms of the human digestive tract, also act as a catalyst in generating biodiesel by converting inexpensive sugars into fatty acid derivatives that are chemically similar to gasoline.
But E. coli's natural conversion capability is not up to snuff, commercially speaking, and researchers tinkering with its internal machinery have yet to boost its capability enough to cross the commercial threshold.
So Chaitan Khosla, a Stanford professor of chemistry and of chemical engineering, decided to investigate whether there might be a natural limit that holds back E. coli's conversion capabilities. In other words, does the basic catalytic engine in E. coli have enough horsepower to do the job at the needed scale?
A powerful engine
"The good news is that the engine that makes fatty acids in E. coli is incredibly powerful," Khosla said. "It is inherently capable of converting sugar into fuel-like substances at an extraordinary rate. The bad news is this engine is subject to some very tight controls by the cell."
It turns out that like any high performance engine, the catalytic process in E. coli can only attain peak efficiency when all the controls are tuned just right. The research is described in a paper published in Proceedings of the National Academy of Sciences. Khosla is a coauthor of the paper, which is available online.
Scientists don't yet understand how all the cellular controls operate. It will require a deeper understanding of the biochemistry of E. coli than they have now to figure that out, Khosla said. But his research team is making progress homing in on the most promising part of the conversion process, thanks in part to a new approach they employed in their analysis.
The researchers managed to isolate all the enzymes and other molecular participants involved in the process that produces fatty acids in E. coli and assemble them in a test tube for study.
"We wanted to understand what limits the ability of E. coli to process sugar into oil. The question we were asking is analogous to asking what limits the speed of my Honda to 150 miles an hour and no faster?" Khosla said. "The most direct and powerful way to figure it out is to pull the biosynthetic engine out of the cell and put it through its paces in a test tube."
By doing so, the team was able to study how the enzymes involved in fatty acid biosynthesis performed when they were free from other cellular influences. That was critical to their analysis, because the products in question, fatty acids, are essentially soap, Khosla said, and too much of them would hurt the bacteria. That is why E. coli has developed some very elaborate and effective ways to contain the amount of fatty acid biosynthesis inside the cell.

Precursor to biodiesel

The fatty acids can't be pumped directly into your gas tank – cars and trucks won't run on soap, after all – but they are an excellent precursor to biodiesel.
Biodiesel has so far lagged behind ethanol as a means of cutting fossil fuel use in vehicles because ethanol is easier and cheaper to make. But biodiesel has a higher energy density and lower water solubility than ethanol, which offer significant advantages.
"It is closer in chemical properties to a barrel of oil from Saudi Arabia than any other biologically derived fuel," Khosla said. Thus it could easily be blended into diesel and gasoline, or used alone as a bona fide transportation fuel.
If researchers can figure out how to manipulate the cellular means of production in E. coli, biodiesel could be made cheaply enough that the little engine of E. coli could end up powering a lot of larger engines at far less cost to the environment than with fossil fuels.
Xingye Yu, graduate student in chemical engineering, and Tiangang Liu, postdoctoral scholar in chemistry, contributed equally to the research and are coauthors of the paper.

(PhysOrg.com)

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Farmer Finds Rare Meteorite

It wasn't a goose that laid a golden egg for one Missouri farmer -- it was an asteroid.

(Washington University in St. Louis geochemist Randy Korotev with the Conception Junction meteorite. His lab analyzed the olivine crystals in the rock. Credit: Dave Gheesling/WUSTL)

Scientists are analyzing an extremely rare meteorite found by a farmer in a tiny Missouri town called Conception Junction (population 202), reports Washington University in St. Louis, which helped identify the rock.
An unnamed farmer had found the unusually heavy stone buried in the side of a hill. He sawed off the end of the stone and realized he had something that didn't come from Earth.
The metal rock is studded on the inside with green olivine crystals. It is one of only 20 so-called pallasitemeteorites that have been found in the United States.
These types of meteorites are believed to be fragments of large asteroids that had enough internal heat to begin melting, which allowed heavy metals to sink and form a core, while lighter elements became part of the rocky surface.
Pallasites are believed to come from the area where an asteroid's metal core transitions to olivine in its lower mantle.
Scientists believe the Conception Junction meteorite was once part of an asteroid that flew in the main asteroid belt between Mars and Jupiter, until it was nudged toward the inner solar system by Jupiter's gravity field.
Sliced and polished, the stone, which is now in the hands of private collectors, is worth about $200 a gram.

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Two Dwarfs Spotted Hanging-Out With Andromeda

Our galaxy lives in a pretty typical, boring region of of the cosmic web of galaxies in what we call "The Local Group." It is dominated by Andromeda and the Milky Way, but has a whole host of smaller galaxies associated with these two giants.

Images: Top - Andromeda XXIX, outlined in yellow for clarity. Credit - Gemini Observatory/AURA/Eric Bell; Middle - Model of the Local Group. Credit - Richard Powell; Bottom - It's not that obvious in the sky, but the Sagittarius dwarf galaxy has left a stream of stars around the Milky Way. Credit - David Law, UCLA.

Most of these galaxies are dwarf galaxies, and this shouldn't be too surprising. From planetary bodies to stars to galaxies, the universe tends to make a lot of "little" things and very few spectacularly large ones.
There are something like a hundred galaxies in the Local Group when you add up all the dwarf galaxies. The exact number is hard to determine, as there is some debate over whether some objects are "really" galaxies or just a chance grouping of stars.
These two new dwarf galaxies are named Andromeda XXVIII and Andromeda XXIX, because, again, astronomers are so clever at naming things, and these are the 28th and 29th dwarf galaxies to be found associated with the Andromeda Galaxy. Both are actually a bit far removed from the large spiral, and thus may clue us in to how dwarf galaxies look before they get too close to a big galaxy.
What happens when a little galaxy gets too close? Well, just ask the famous Sagittarius dwarf galaxy, if you can. It's been gravitationally ripped to shreds, leaving a stream of stars looping around the Milky Way at least twice. The "galactic cannibalism" is how large galaxies grow larger over time, consuming the myriad of smaller galaxies.
Since these galaxies are so faint, we can really only study the ones that live in our Local Group and extrapolate to other galaxy groups. However, being in the middle of our galaxy's disk means that our view isn't necessarily unobstructed.
Finding and classifying new dwarf galaxies is painstaking work. Will there ever be an end? Will there be something too small to classify as a galaxy and a Pluto-like debate over its name? Probably, but finding out how the universe works is way more interesting than agonizing over a name.
This research has been published in Astrophysical Journal Letters, and the preprints can be found at arxiv.org.
Discovery News

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New H2O Discovered

Ice block at beach near Jökulsárlón, Iceland. (Wikimedia Commons)

Besides vapor, ice and liquid, a fourth form of water may exist, but don't worry, Kurt Vonnegut fans, it's not ice-nine, the dangerous, solid at room temperature substance from the book Cat's Cradle. Unlike the fictional ice-nine, which melted at 114 degrees Fahrenheit, this new form of H2O likes it cold, about 54 degrees below zero Fahrenheit.
Liquid water usually freezes into ice at 32 Fahrenheit, but under the right conditions, like the high pressure at the bottom of the ocean, water stays liquid below 32 Fahrenheit.
Water's fourth form, or phase, may be a liquid with some of the properties of both ice and regular liquid water. But laboratory equipment isn't sensitive enough to observe the rapid transformation from regular liquid water to the fourth form.
Researchers Pradeep Kumar and H. Eugene Stanley used a computer simulation to model the elusive liquid. They found that at about 54 degrees below zero Fahrenheit, the local structure of water seems to become extremely ordered, like ice, while undergoing sharp but continuous structural changes and remaining liquid.
Oddly, at this temperature the water also became more conductive of heat, the opposite of what happens with regular liquid water and ice, as anyone living in an igloo will tell you.
The strange behavior of water at low temperatures is what led Stanley and Kumar to believe that their results support the idea that water has a fourth phase.

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Electronic nose aims to sniff out disease

Dr. Ranjan Nanda demonstrates the device at an experimental stage. The electronic nose aims to diagnose tuberculosis without a lab test.

A breathalyzer-like device that aims to detect tuberculosis, pneumonia and lung cancer from someone's breath could help replace time-consuming tests, researchers hope.

The electronic nose received a $950,000 grant from the federally funded Grand Challenges Canada and the Bill & Melinda Gates Foundation on Monday, to try to develop the hand-held device for use in the developing world.

"It's almost like a breathalyzer test that the police might use for alcohol," Dr. Peter Singer, CEO of Grand Challenges Canada, said in an interview from New Delhi.

"If they can bring that to the window of your car, what we're trying to do is bring the diagnosis of tuberculosis to the door of the hut in the village where it really needs to reach."

Scientists say electronic noses could also be created for early detection of lung cancer and pneumonia, also based on signature biomarkers of disease detectable in a patient's breath.

Singer called the device a "bold idea" with potentially a big payoff in preventing the 1.7 million deaths from TB each year, mainly in the developing world. Up to 400,000 of them could be saved with better diagnosis, he said.

People may not think about diagnosis as life-saving, Singer said. But if a patient in a village isn’t diagnosed, it is very likely many others will be infected and then die.

For the prototype, someone breathes into the device, which has a little tub at the end to capture the sample, which is then tested.

The battery-powered technology is based on the finding that people with TB have a different biological signature in their breath.

The two-year grant will be use to validate the finding in four centres throughout India.

Dr. Ranjan Nanda of the New Delhi-based International Centre for Genetic Engineering and Biotechnology, one of the lead researchers on the electronic nose project, aims to have a validated prototype by December 2013.

If it works, it could be in use shortly after that, Singer said.

The existng sputum test for TB has challenges, especially for developing countries that may not have facilities or trained lab staff, says Dr. Michael Gardam, an infectious disease specialist with Toronto's University Health Network.

"It's just such a wonderful idea and it's such a simple idea," Gardam said. "The challenge is going to be, at the end of the day, can it jump through all the necessary hoops to actually be something that people can use?"

The development of the device is a collaboration between Nanda's centre and and Next Dimension Technologies in California.

CBC News

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Lost Civilization Discovered in Sahara Desert

New evidence of a lost civilization in an area of the Sahara in Libya has emerged from images taken by satellites.

An ancient mudbrick village with a castle-like structure emerges in Libya

Using satellites and air photographs to identify the remains in one of the most inhospitable parts of the desert, a team from the University of Leicester in England has discovered more than 100 fortified farms and villages with castle-like structures and several towns, most dating between AD 1 to 500.

"It is like someone coming to England and suddenly discovering all the medieval castles. These settlements had been unremarked and unrecorded under the Gadhafi regime," said project leader David Mattingly, professor of Roman archaeology at the university. The fall of the regime has opened up Libya to more exploration by archaeologists of its pre-Islamic heritage.
These "lost cities" were built by a little-known ancient civilization called the Garamantes, whose lifestyle and culture was far more advanced and historically significant than ancient sources had suggested.

Castle-like complexes
The team from the University of Leicester has identified the mud brick remains of the castle-like complexes, with walls still standing up to 13 feet (4 meters) high, along with traces of dwellings, cairn cemeteries, associated field systems, wells and sophisticated irrigation systems. Follow-up ground surveys earlier this year confirmed the pre-Islamic date and remarkable preservation of the sites.

"Satellite imagery has given us the ability to cover a large region. The evidence suggests that the climate has not changed over the years and we can see that this inhospitable landscape with zero rainfall was once very densely built up and cultivated. These are quite exceptional ancient landscapes, both in terms of the range of features and the quality of preservation," said Martin Sterry, who has been responsible for much of the image analysis and site interpretation.
The findings challenge a view dating back to Roman accounts that the Garamantes consisted of barbaric nomads and troublemakers on the edge of the Roman Empire.

"In fact, they were highly civilized, living in large-scale fortified settlements, predominantly as oasis farmers. It was an organized state with towns and villages, a written language and state of the art technologies. The Garamantes were pioneers in establishing oases and opening up trans-Saharan trade," Mattingly said.
Libyan heritage
The professor and his team were forced to evacuate Libya in February when the anti-Gadhafi revolt started, but hope to be able to return to the field as soon as security is fully restored. The Libyan antiquities department, badly neglected under Gadhafi, is closely involved in the project.
"It is a new start for Libya's antiquities service and a chance for the Libyan people to engage with their own long-suppressed history," Mattingly said. "These represent the first towns in Libya that weren't the colonial imposition of Mediterranean people such as the Greeks and Romans. The Garamantes should be central to what Libyan school children learn about their history and heritage."
The research is funded by the European Research Council, the Leverhulme Trust, the Society for Libyan Studies and the GeoEye Foundation.

| LiveScience

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Mars Rover Discovers 'A Completely New Thing'

 While looking for a safe place to weather the cold Martian winter, the rover Opportunity spied a subtle yet intriguing feature on the edge of the giant Endeavour crater: a bright vein of light-toned rock piercing the ruddy, rocky surface of a large rise called Cape York.

Seen above running horizontally at center, in an image colored by Stuart Atkinson, the vein (dubbed "Homestake") may prove to be hard evidence of phyllosilicates -- minerals formed in the presence of a watery environment. If this is the case then this chance discovery would mean that Opportunity, after nearly eight years on Mars, has literally stumbled upon the "Holy Grail" of its entire mission!
Data from the Mars Reconnaissance Orbiter has already identified the region around Endeavour Crater as containing phyllosilicates, specifically iron- and magnesium-rich clays known as "smectites". These minerals are sure signs of past water... most likely salty water that could have been highly conducive to the development of life.
Identifying chemical signatures from orbit is one thing, though... finding and studying actual outcroppings of phyllosilicates at ground level is something else entirely. And this is precisely what the MER team has been hoping Opportunity will do at Endeavour.
"This is a real triumph of geology," said Steve Squyres, Mars Exploration Rover principal investigator at Cornell University. "We saw these veins as we crossed from the Meridiani plains into the Noachian terrain back in August. We've kept those in mind as a very important thing we wanted to look at, but we were so focused on getting into the Noachian and new terrain that we made that the highest priority, figuring that we would get the veins later."
It looks like "later" is now.

A closer look at Homestake with Opportunity's microscopic camera shows a bright surface gouged by linear scratches. This view, a composite of three separate images also by Stu Atkinson, gives a closer look:
The MER team hasn't officially stated what they believe the vein may be composed of but they definitely sound intrigued.
"These are different than anything from anything we've ever seen with either rover, a completely new thing on Mars, never seen anywhere," Squyres said. "And we're pretty charged up about it."
In the meantime the rest of us will have to wait for further information.
Opportunity is now facing its fifth Martian winter and the MER team must soon plan driving maneuvers to place it at a prime location to weather the long months of frigid temperatures and reduced sunlight. Most importantly it will need to find a north-facing slope that will position it at a ten- to fifteen-degree angle, to take best advantage of the available sunlight on its already dusty solar panels. While this potential discovery is undoubtedly exciting, Opportunity's ultimate survival must take precedence.
Once the six-month-long Martian winter is over, Opportunity can resume exploration of the area around Cape York, an area that has already proven itself to hold promises of many never-before-seen features.
"All the rocks we're seeing here are completely different than Opportunity has ever seen and different significantly than the rocks Spirit saw as well," said Bruce Banerdt, MER project scientist at JPL. "So we're already picking up new geology and new rocks and new petrology that no one's ever encountered yet on the Martian surface. It's all great stuff. There is a lot of activity going on and the science team is really jazzed right now."
Find out more in the Mars Exploration Rover 2011 Update on The Planetary Society blog, and keep up with Opportunity's progress on Stu Atkinson's blog The Road to Endeavour.
Image credits: NASA/JPL-Caltech. Edited by Stu Atkinson.

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Huge Crack Discovered in Pine Island Glacier, Antarctica

A huge, emerging crack has been discovered in one of Antarctica's glaciers, with a NASA plane mission providing the first-ever detailed airborne measurements of a major iceberg breakup in progress

In October, 2011, NASA's Operation IceBridge discovered a major rift in the Pine Island Glacier in western Antarctica.NASA

NASA's Operation Ice Bridge, the largest airborne survey of Earth's polar ice ever flown, is in the midst of its third field campaign from Punta Arenas, Chile. The six-year mission will yield an unprecedented three-dimensional view of Arctic and Antarctic ice sheets, ice shelves and sea ice. The glaciers of the Antarctic, and Greenland, Ice Sheets, commonly birth icebergs that break off from the main ice streams where they flow in to the sea, a process called calving.

The crack was found in Pine Island Glacier, which last calved a significant iceberg in 2001; some scientists have speculated recently that it was primed to calve again. But until an Oct. 14 IceBridge flight, no one had seen any evidence of the ice shelf beginning to break apart. Since then, a more detailed look back at satellite imagery seems to show the first signs of the crack in early October.

"We are actually now witnessing how it happens and it's very exciting for us," said IceBridge project scientist Michael Studinger of NASA's Goddard Space Flight Center in Greenbelt, Md. "It's part of a natural process, but it’s pretty exciting to be here and actually observe it while it happens."

Gravity pulls the ice in the glacier westward along Antarctica's Hudson Mountains toward the Amundsen Sea. A floating tongue of ice reaches out 30 miles (48 kilometers) into the Amundsen beyond the grounding line, the below-sea-level point where the ice shelf locks onto the continental bedrock. As ice pushes toward the sea from the interior, inevitably the ice shelf will crack and send a large iceberg free.

Pine Island Glacier is of particular interest to scientists because it is big and unstable and so is one of the largest sources of uncertainty in global sea level rise projections.

A primary goal of Operation IceBridge is to put the same instruments over the exact same flight lines and satellite tracks, year after year, to gather meaningful and accurate data of how ice sheets and glaciers are changing over time. But discovering a developing rift in one of the most significant science targets in the world of glaciology offered a brief change in agenda for the Oct. 26 flight, if only for a 30-minute diversion from the day's prescribed flight lines.

The IceBridge team observed the rift running across the ice shelf for about 18 miles (29 km), using an instrument called the Airborne Topographic Mapper, which uses a technology called lidar (light detection and ranging) that sends out a laser beam that bounces off a surface and back to the device. The lidar instrument measured the rift's shoulders about 820 feet (250 meters) apart at its widest, although the rift stretched about 260 feet (79 meters) wide along most of the crack. The deepest points from the ice shelf surface ranged from 165 to 195 feet (50 to 60 meters).

When the iceberg breaks free, it will cover about 340 square miles (880 square kilometers) of surface area. Radar measurements suggested the ice shelf in the region of the rift is about 1,640 feet (500 meters) feet thick, with only about 160 feet of the shelf floating above water and the rest submerged.

It is likely that once the iceberg floats away, the leading edge of the ice shelf will have receded farther than at any time since its location was first recorded in the 1940s. 

Source: OurAmazingPlanet

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Tiny but toothy mammal unearthed

What the animal did with those impressive canines is not exactly clear

An extraordinary looking, mouse-sized, fossil animal is shedding new light on the ancient history of mammals.
With a thin snout, beady eyes and long canines, the creature would have looked remarkably like that fictional sabre-toothed squirrel of Ice Age movie-fame.
But Cronopio dentiacutus is one of the very few mammal specimens to come out of South America from the era when dinosaurs ruled the Earth.
The 100-million-year-old animal is reported in the journal Nature.
It was discovered in sandstone sediments at Cipolletti, Rıo Negro Province, Argentina.
Those ancient river sediments reveal a lot about what the local environment was like in the Late Cretaceous, but scientists are struggling to pin down the details of Cronopio's lifestyle.
The animal displays a host of features that appear to have no parallel among living or extinct mammals, says Prof Guillermo Rougier from the University of Louisville, Kentucky, US.
"The back teeth, the molars, are the kind of teeth that you will find in an insectivore, an animal that eats insects of different kinds, and even very small invertebrates, so perhaps small lizards, which were present in the same place," he told BBC News.
"But we have no idea why he needed such huge canines. Those tusks are a big surprise."
It is possible Cronopio used them to skewer certain insect prey, but it is clear the canines could not have been deployed with much force.

Skulls (G.Rougier)

The slender nature of the snout and the teeth themselves mean that to have bitten down hard, or to have wrestled another creature with its mouth, would have invited almost certain injury.
Cronopio is what is termed a dryolestoid. These were a group of primitive, extinct mammals belonging to the lineage leading to modern marsupials and placental mammals.
They are known mainly from teeth and jaws found in North America and Europe from the Jurassic Period (145-200 million years ago). To now have relatively complete dryolestoid skulls form South America in the form of Cronopio is therefore a boon to scientists trying to study the spread and diversity of mammals through Earth history.
There are so few well-preserved South American mammals from the time of the dinosaurs
"In the northern continents, there is a longer tradition of palaeontology and so they are well represented," observed Prof Rougier.
"In South America, Africa and Australia - not so much work has been done proportionately, and so we know very little; and that's why Cronopio is so important.
"Instead of having a picture that is so heavily biased to what happened in the North, we're starting to get some information about what happened in the southern continents, and fortunately in this case the quality of the specimens is very good."
As to that likeness with Scrat, the acorn-obsessed squirrel in the animated Ice Age features films, Prof Rougier finds the association highly amusing.
"I remember when I saw the movie I thought, 'why have they done this ridiculous animal - there is no such thing?'. And then we find something that kind of looks like it. But it just goes to show - we know so little about the actual diversity of mammals that even some very wild guesses might come through; they might actually be present

 BBC News

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First Known Europeans Identified

The earliest Europeans lived around 45,000 years ago and shared turf with Neanderthals.

A baby molar tooth from what is believed to be the remains of the first European anatomically modern human. credit: Stefano Benazzi

THE GIST

The earliest known Homo sapiens in Europe lived in a southern Italian cave 45,000 years ago.
Modern humans were also in what is now the U.K. about 44,000 years ago.
Together, the studies show that our species quickly spread over Europe and coexisted with Neanderthals.

Europe's earliest known modern humans existed around 45,000 years ago in a southern Italian prehistoric cave, according to new research.
The discovery means that members of our own species have been present in Europe longer than previously thought, sharing turf with Neanderthals for at least 5,000 years.
"During this time it is very likely that some contact must have been achieved, but there is no direct evidence for it," Stefano Benazzi, a physical anthropologist at the University of Vienna, told Discovery News.
He explained that "Neanderthals must have survived until about 40,000 years ago."
Before the findings of Benazzi and his team, the first known modern humans in Europe came from Romania and dated to 40,000 years ago. Early Upper Paleolithic modern human cultures are documented in the Near East to about 45,000 years ago, which previously left a gap of 5,000 years between these Homo sapiens and the ones from Romania.
"With our findings, the gap is filled," said Benazzi, whose research was published this week in the journal Nature.
Benazzi and his colleagues analyzed two teeth unearthed in 1964 at Grotta del Cavallo, a prehistoric cave in what is now Puglia. During the 1960's, the teeth were identified as coming from Neanderthals.
Benazzi and his team, however, used the latest technology, including digital models from CT scans, to examine the teeth and compare them to others belonging to Neanderthals and our species. They found that the internal and external features of the teeth better match those of modern humans.
Strengthening the determination is yet another Nature paper by a different team. That study reexamined another fossil -- in this case a jaw -- once attributed to a Neanderthal.
The new analysis determined the jaw belonged to an early modern human who lived between 44,200-41,500 years ago in what is now close to Torquay, United Kingdom.
The teeth belonged to members of what is called the Uluzzian culture. These individuals were known for fairly sophisticated bone tools, shell beads and mineral colorants that indicate these people were interested in symbolic behavior, such as wearing jewelry and sporting tattoos.
Many papers have attributed such behavior to Neanderthals in the region, but now that's in question.
Benazzi said the new findings do not provide any evidence of how the people first came to Europe, "but it is most likely that the first settlers arrived from the east, maybe along the Danube corridor."
He added, "An inherent problem in studying Pleistocene populations (prior to the Holocene or the last 10,000 years) is that the landscape has changed dramatically and large regions of the continent are now submerged. Seafaring across the Mediterranean could be a possibility, but again we have no evidence for this at the moment."
Thomas Higham of the University of Oxford, who co-authored the other Nature paper, said the new studies tell "us a great deal about how rapidly our species dispersed across Europe during the last Ice Age."
He said the discoveries also mean "that early humans must have co-existed with Neanderthals in this part of the world, something which a number of researchers have doubted."
Gerhard Weber, deputy head of the University of Vienna's Department of Anthropology, points out the studies were "made possible through technical innovations developed in the last decade."
Weber predicts that these new techniques, associated with tooth and fossil analysis as well as radiocarbon dating, will help to resolve more questions regarding "other contentious human fossil remains."
It could be that many fossils previously thought to belong to Neanderthals actually were from early modern humans.

Source: Discovery News

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Complex organic matter discovered throughout the Universe

A spectrum from the Infrared Space Observatory superimposed on an image of the Orion Nebula where the complex organics are found
Researchers at the University of Hong Kong (HKU) claim to have solved the mystery of "Unidentified Infrared Emission features" that have been detected in stars, interstellar space, and galaxies. For over two decades, the most commonly accepted theory regarding this phenomenon was that these signatures come from polycyclic aromatic hydrocarbon (PAH) molecules - simple organic molecules made of carbon and hydrogen atoms. Now HKU researchers say the substances generating these signatures are actually complex organic compounds that are made naturally by stars and ejected into interstellar space.
The team of Prof. Sun Kwok and Dr. Yong Zhang used observations taken by the Infrared Space Observatory and the Spitzer Space Telescope of stardust formed in exploding stars called novae to show that the astronomical spectra contain a mixture of aromatic (ring-like) and aliphatic (chain-like) components that cannot be explained by PAH molecules.
The researchers say the substances generating these infrared emissions actually have chemical structures that are so complex that their structure resembles those of coal and petroleum. Since coal and petroleum are remnants of ancient life and this type of organic matter was only thought to arise from living organisms, the researchers say this suggests that complex organic compounds can be synthesized in space even when no life forms are present.

Supporting an earlier idea by Kwok that old stars are molecular factories capable of manufacturing organic compounds, they say that not only are stars producing this complex matter on extremely short time scales of weeks, but they are also ejecting it into the general interstellar space in between stars.
"Our work has shown that stars have no problem making complex organic compounds under near-vacuum conditions," says Kwok. "Theoretically, this is impossible, but observationally we can see it happening."
As the organic stardust is similar in structure to complex organic compounds found in meteorites, the findings raise the possibility that stars enriched the early solar system with organic compounds. With the Earth being bombarded by comets and meteorites early in its life that could potentially have carried the organic stardust, there is a possibility that the seeds of life on Earth were sown by organic compounds created naturally by stars. If that turns out to be the case, it has obvious implications for the chances of life outside our solar system as the complex organic compounds exist throughout the Universe.
Kwok and Zhang's Paper, Mixed aromatic-aliphatic organic nanoparticles as carriers of unidentified infrared emission features is published this month in the journal Nature

( VIA GIZMAG)

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Strawberries protect stomach from alcohol

In an experiment on rats, European researchers have proved that eating strawberries reduces the harm that alcohol can cause to the stomach mucous membrane. Published in the open access journal Plos One, the study may contribute to improving the treatment of stomach ulcers.
A team of Italian, Serbian and Spanish researchers has confirmed the protecting effect that strawberries have in a mammal stomach that has been damaged by alcohol. Scientists gave ethanol (ethyl alcohol) to laboratory rats and, according to the study published in the journal Plos One, have thus proved that the stomach mucous membrane of those that had previously eaten strawberry extract suffered less damage.
Sara Tulipani, researcher at the University of Barcelona (UB) and co-author of the study explains that “the positive effects of strawberries are not only linked to their antioxidant capacity and high content of phenolic compounds (anthocyans) but also to the fact that they activate the antioxidant defences and enzymes of the body.”
The conclusions of the study state that a diet rich in strawberries can have a beneficial effect when it comes to preventing gastric illnesses that are related to the generation of free radicals or other reactive oxygen species. This fruit could slow down the formation of stomach ulcers in humans.
Gastritis or inflammation of the stomach mucous membrane is related to alcohol consumption but can also be caused by viral infections or by nonsteroidal anti-inflammatory medication (such as aspirin) or medication used to treat against the Helicobacter pylori bacteria.
Maurizio Battino, coordinator of the research group at the Marche Polytechnic University (UNIVPM, Italy) suggests that “in these cases, the consumption of strawberries during or after pathology could lessen stomach mucous membrane damage.”
The team found less ulcerations in the stomachs of those rats which had eaten strawberry extract (40 milligrams/day per kilo of weight) for 10 days before being given alcohol.
Battino emphasises that “this study was not conceived as a way of mitigating the effects of getting drunk but rather as a way of discovering molecules in the stomach membrane that protect against the damaging effects of differing agents.”
Treatments for ulcers and other gastric pathologies are currently in need of new protective medicines with antioxidant properties. The compounds found within strawberries could be the answer.

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Strange Hollows Discovered on Mercury

Oct 24, 2011: NASA's MESSENGER spacecraft has discovered strange hollows on the surface of Mercury. Images taken from orbit reveal thousands of peculiar depressions at a variety of longitudes and latitudes, ranging in size from 60 feet to over a mile across and 60 to 120 feet deep. No one knows how they got there.
(Image on the left-Hollows inside the Raditladi impact basin. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

"These hollows were a major surprise," says David Blewett, science team member from the Johns Hopkins University Applied Physics Laboratory. "We've been thinking of Mercury as a relic – a place that's really not changing much anymore, except by impact cratering. But the hollows appear to be younger than the craters in which they are found, and that means Mercury's surface is still evolving in a surprising way."
Mars Reconnaissance Orbiter spotted similar depressions in the carbon dioxide ice at Mars' south pole, giving that surface a "swiss cheese" appearance. But on Mercury they're found in rock and often have bright interiors and halos.

"We've never seen anything quite like this on a rocky surface."

If you could stand in one of these "sleepy" hollows on Mercury's surface, you'd find yourself, like Ichabod Crane, in a quiet, still, haunting place, with a black sky above your head.
"There's essentially no atmosphere on Mercury," explains Blewett. "And with no atmosphere, wind doesn't blow and rain doesn't fall. So the hollows weren't carved by wind or water. Other forces must be at work."
As the planet closest to the Sun, Mercury is exposed to fierce heat and extreme space weather. Blewett believes these factors play a role.

 Another example of hollows in crater Tyagaraja. Courtesy Science/AAAS

A key clue, he says, is that many of the hollows are associated with central mounds or mountains inside Mercury's impact craters. These so-called “peak rings” are thought to be made of material forced up from the depths by the impact that formed the crater. Excavated material could be unstable when it finds itself suddenly exposed at Mercury's surface.
"Certain minerals, for example those that contain sulfur and other volatiles, would be easily vaporized by the onslaught of heat, solar wind, and micrometeoroids that Mercury experiences on a daily basis," he says. "Perhaps sulfur is vaporizing, leaving just the other minerals, and therefore weakening the rock and making it spongier. Then the rock would crumble and erode more readily, forming these depressions."

 A fresh impact crater. Hollows are present on a section of the crater wall that has slid partway down toward the floor. Courtesy  Science/AAAS

MESSENGER has indeed proven Mercury unexpectedly rich in sulfur. That in itself is a surprise that's forcing scientists to rethink how Mercury was formed. The prevailing models suggest that either
(1) very early in Solar System history, during the final sweep-up of the large planetesimals that formed the planets, a colossal impact tore off much of Mercury's rocky outer layering; or
(2) a hot phase of the early Sun heated up the surface enough to scorch off the outer layers. In either case, the elements with a low boiling point – volatiles like sulfur and potassium – would have been driven off.
But they're still there.
"The old models just don't fit with the new data, so we'll have to look at other hypotheses."
To figure out how the planets and Solar System came to be, scientists must understand Mercury.
"It's the anchor at one end of the Solar System. Learning how Mercury formed will have major implications for the rest of the planets. And MESSENGER is showing that, up to now, we've been completely wrong about this little world in so many ways!"
What other surprises does Mercury hold? The sleepy hollows of the innermost planet may be just the beginning.
Credit: Science@NASA

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Nearby Planet-Forming Disk Holds Water for Thousands of Oceans

An illustration depicting the sprawling cloud of cold water vapor that astronomers have detected around the burgeoning solar system at the nearby star TW Hydrae. The cold water vapor could could eventually deliver oceans to dry planets that are forming in the system. (Credit: NASA/JPL-Caltech/T. Pyle (SSC/Caltech))
For the first time, astronomers have detected around a burgeoning solar system a sprawling cloud of water vapor that's cold enough to form comets, which could eventually deliver oceans to dry planets.
Water is an essential ingredient for life. Scientists have found thousands of Earth-oceans' worth of it within the planet-forming disk surrounding the star TW Hydrae. TW Hydrae is 176 light years away in the constellation Hydra and is the closest solar-system-to-be.
University of Michigan astronomy professor Ted Bergin is a co-author of a paper on the findings published in the Oct. 21 edition of Science.
The researchers used the Heterodyne Instrument for the Far-Infrared (HIFI) on the orbiting Hershel Space Observatory to detect the chemical signature of water.
"This tells us that the key materials that life needs are present in a system before planets are born," said Bergin, a HIFI co-investigator. "We expected this to be the case, but now we know it is because have directly detected it. We can see it."
Scientists had previously found warm water vapor in planet-forming disks close to the central star. But until now, evidence for vast quantities of water extending into the cooler, far reaches of disks where comets and giant planets take shape had not emerged. The more water available in disks for icy comets to form, the greater the chances that large amounts will eventually reach new planets through impacts.
"The detection of water sticking to dust grains throughout the planet-forming disk would be similar to events in our own solar system's evolution, where over millions of years, these dust grains would then coalesce to form comets. These would be a prime delivery mechanism for water on planetary bodies," said principal investigator Michiel Hogerheijde of Leiden University in the Netherlands.
Other recent findings from HIFI support the theory that comets delivered a significant portion of Earth's oceans. Researchers found that the ice on a comet called Hartley 2 has the same chemical composition as our oceans.
HIFI is helping astronomers gain a better understanding of how water comes to terrestrial planets -- Earth and beyond. If TW Hydrae and its icy disk are representative of many other young star systems, as researchers think they are, then the process for creating planets around numerous stars with abundant water throughout the universe appears to be in place, NASA officials say.
University of Michigan.

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Giant Amoebas Discovered in Deepest Ocean Trench

Gigantic amoebas have been found in the Mariana Trench, the deepest region on Earth.

National Geographic Society Remote Imaging engineers Eric Berkenpas (bottom) and Graham Wilhelm prepare to deploy Dropcam. CREDIT: National Geographic Society Remote Imaging Dropcam

During a July 2011 voyage to the Pacific Ocean chasm, researchers with Scripps Institution of Oceanography at UC San Diego and National Geographic engineers deployed untethered landers, called dropcams, equipped with digital video and lights to explore the largely mysterious region of the deep sea.
The team documented the deepest known existence of xenophyophores, single-celled animals exclusively found in deep-sea environments. Xenophyophores are noteworthy for their size, with individual cells often exceeding 4 inches (10 centimeters), their extreme abundance on the seafloor and their role as hosts for a variety of organisms.

Extreme environment, extreme creature

The researchers spotted the life forms at depths up to 6.6 miles (10,641 meters) within the Sirena Deep of the Mariana Trench. The previous depth record for xenophyophores was approximately 4.7 miles (7,500 m) in the New Hebrides Trench, although sightings in the deepest portion of the Mariana Trench have been reported.
Scientists say xenophyophores are the largest individual cells in existence. Recent studies indicate that by trapping particles from the water, xenophyophores can concentrate high levels of lead, uranium and mercury and are thus likely resistant to large doses of heavy metals. They also are well suited to a life of darkness, low temperature and high pressure in the deep sea.
"The identification of these gigantic cells in one of the deepest marine environments on the planet opens up a whole new habitat for further study of biodiversity, biotechnological potential and extreme environment adaptation," said Doug Bartlett, the Scripps marine microbiologist who organized the expedition.

Tip of the iceberg

The xenophyophores are just the tip of the deep-sea ecosystem iceberg. The expedition also found the deepest jellyfish observed to date, as well as other mysterious animals.
"As one of very few taxa found exclusively in the deep sea, the xenophyophores are emblematic of what the deep sea offers. They are fascinating giants that are highly adapted to extreme conditions but at the same time are very fragile and poorly studied," Levin said. "These and many other structurally important organisms in the deep sea need our stewardship as human activities move to deeper waters."
The dropcams used to observe the creatures contained an HD camera and lighting inside a glass bubble that can withstand the extreme pressures encountered at these depths.
"Seafloor animals are lured to the camera with bait, a technique first developed by Scripps professor John Isaacs in the 1960s," said Kevin Hardy, a Scripps ocean engineer and cruise participant. Hardy advanced the ultra-deep glass sphere design used on 'dropcams' more than a decade ago. "Scripps researchers hope to one day capture and return novel living animals to the laboratory for study in high-pressure aquariums that replicate the trench environment."

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NASA's Spitzer Detects Comet Storm in Nearby Solar System

This artist's conception illustrates a storm of comets around a star near our own, called Eta Corvi. Evidence for this barrage comes from NASA's Spitzer Space Telescope, whose infrared detectors picked up indications that one or more comets was recently torn to shreds after colliding with a rocky body. (Credit: NASA/JPL-Caltech)
NASA's Spitzer Space Telescope has detected signs of icy bodies raining down in an alien solar system. The downpour resembles our own solar system several billion years ago during a period known as the "Late Heavy Bombardment," which may have brought water and other life-forming ingredients to Earth.
During this epoch, comets and other frosty objects that were flung from the outer solar system pummeled the inner planets. The barrage scarred our moon and produced large amounts of dust.
Now Spitzer has spotted a band of dust around a nearby bright star in the northern sky called Eta Corvi that strongly matches the contents of an obliterated giant comet. This dust is located close enough to Eta Corvi that Earth-like worlds could exist, suggesting a collision took place between a planet and one or more comets. The Eta Corvi system is approximately one billion years old, which researchers think is about the right age for such a hailstorm.
"We believe we have direct evidence for an ongoing Late Heavy Bombardment in the nearby star system Eta Corvi, occurring about the same time as in our solar system," said Carey Lisse, senior research scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., and lead author of a paper detailing the findings. The findings will be published in the Astrophysical Journal. Lisse presented the results at the Signposts of Planets meeting at NASA's Goddard Space Flight Center in Greenbelt, Md., on Oct. 19.
Astronomers used Spitzer's infrared detectors to analyze the light coming from the dust around Eta Corvi. Certain chemical fingerprints were observed, including water ice, organics and rock, which indicate a giant comet source.
The light signature emitted by the dust around Eta Corvi also resembles the Almahata Sitta meteorite, which fell to Earth in fragments across Sudan in 2008. The similarities between the meteorite and the object obliterated in Eta Corvi imply a common birthplace in their respective solar systems.
A second, more massive ring of colder dust located at the far edge of the Eta Corvi system seems like the proper environment for a reservoir of cometary bodies. This bright ring, discovered in 2005, looms at about 150 times the distance from Eta Corvi as Earth is from the sun. Our solar system has a similar region, known as the Kuiper Belt, where icy and rocky leftovers from planet formation linger. The new Spitzer data suggest that the Almahata Sitta meteorite may have originated in our own Kuiper Belt.
The Kuiper Belt was home to a vastly greater number of these frozen bodies, collectively dubbed Kuiper Belt objects. About 4 billion years ago, some 600 million years after our solar system formed, scientists think the Kuiper Belt was disturbed by a migration of the gas-giant planets Jupiter and Saturn. This jarring shift in the solar system's gravitational balance scattered the icy bodies in the Kuiper Belt, flinging the vast majority into interstellar space and producing cold dust in the belt. Some Kuiper Belt objects, however, were set on paths that crossed the orbits of the inner planets.
The resulting bombardment of comets lasted until 3.8 billion years ago. After comets impacted the side of the moon that faces Earth, magma seeped out of the lunar crust, eventually cooling into dark "seas," or maria. When viewed against the lighter surrounding areas of the lunar surface, those seas form the distinctive "Man in the Moon" visage. Comets also struck Earth or incinerated in the atmosphere, and are thought to have deposited water and carbon on our planet. This period of impacts might have helped life form by delivering its crucial ingredients.
"We think the Eta Corvi system should be studied in detail to learn more about the rain of impacting comets and other objects that may have started life on our own planet," Lisse said.
NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the Spitzer mission for the agency's Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
 Credit: NASA/Jet Propulsion Laboratory

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UFO-Like Stealth Drone Soars in Navy Test Flight

Military drones have already begun edging out manned fighter jets and bombers over the past decade, and the U.S. Navy doesn't plan on being left behind. Its vision for unmanned aerial warfare includes a tailless robotic aircraft resembling a UFO that is scheduled to begin landing on aircraft carriers in 2013. As a step toward that goal, the X-47B drone recently made its first flight in cruise mode with retracted landing gear.
The Navy has enlisted the X-47B drone — a Northrop Grumman design with a stealthy profile — as more than just its very first carrier-based drone. It also wants to use the X-47B as a test platform for autonomous aerial refueling without human assistance in 2014.
"Last week's flight gave us our first clean look at the aerodynamic cruise performance of the X-47B air system … and it is proving out all of our predictions," said Janis Pamiljans, vice president and Navy UCAS program manager for Northrop Grumman's Aerospace Systems sector.
The flight test also served as a trial run for the robotic aircraft's onboard navigation hardware and software. Such robotic brains are designed to help the X-47B take off from and land on the heaving deck of an aircraft carrier.
Planned tests for the drone don't include weapon or sensor demonstrations, but there's no apparent reason why it might not carry weapons in the future. The U.S. military has already demonstrated the lethality of armed drone strikes with its Reaper and Predator unmanned aerial systems in Afghanistan, Iraq and Pakistan, and the Navy has also announced plans to arm ship-based helicopter drones.
The latest test flight took place at Edwards Air Force Base in California.
(Credit:InnovationNewsDaily)

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Youngest Baby Exoplanet Discovered

 The circumstellar disk surrounding the star LkCa 15 (left). Zoomed in, with the light from the star canceled out, the location of the protoplanet can be seen -- the red and blue "blob" (right). Credit: Kraus & Ireland 2011

We know that the planets in our solar system were born from a dusty disk surrounding the sun billions of years ago; wouldn't it be amazing if we could see another star system going through the birthing throes of this protoplanetary phase?
Today, a team of astronomers using the awesome power of the twin 10-meter Keck Telescopes atop Mauna Kea, Hawaii, have announced just that.
For the first time they have directly imaged a baby world forming close to its parent star inside an empty track of a larger disk of dust. This makes it a record-breaker -- the proto(exo?)planet is five-times younger than the youngest exoplanet discovered to date.
The baby world -- called LkCa 15 b -- orbits LkCa 15, a T Tauri star located 450 light-years from Earth that is already known to possess a dusty circumstellar disk.
T Tauri stars are very luminous, young, variable stars. In astronomical timescales, they've recently formed from a cloud of gas under gravitational collapse. The gravitational energy released is what provides the energy to power the star, a phase before nuclear fusion is ignited in their cores.
So, when we observe LkCa 15, we know we are looking at a star that's just starting out, potentially with a whole system of worlds that might form from its protoplanetary disk.
And now we know that there will be at least one world, LkCa 15 b, that Keck can see slowly forming.
"LkCa 15 b is the youngest planet ever found, about 5 times younger than the previous record holder," said astronomer Adam Kraus of the University of Hawaii's Institute for Astronomy. "This young gas giant is being built out of the dust and gas. In the past, you couldn't measure this kind of phenomenon because it's happening so close to the star. But, for the first time, we've been able to directly measure the planet itself as well as the dusty matter around it."
Using a clever trick, Kraus and co-investigator Michael Ireland, of Macquarie University and the Australian Astronomical Observatory, were able to tease out the light being emitted by the dust surrounding the newborn star. They combined the power of Keck's Adaptive Optics with a technique called aperture mask interferometry to manipulate the starlight after it is received by the telescope.
"It's like we have an array of small mirrors," said Kraus. "We can manipulate the light and cancel out distortions." By doing this, the bright light emitted by the star can be canceled out, resolving the faint disks and gaps therein where baby worlds may be hiding. In one of those gaps, LkCa 15 b resides.
The study has been accepted for publication in The Astrophysical Journal.
"We realized we had uncovered a super Jupiter-sized gas planet, but that we could also measure the dust and gas surrounding it. We’d found a planet, perhaps even a future solar system at its very beginning," he adds.
Kraus and Ireland intend to continue surveying other nearby stars to see if similar worlds are forming in the ultimate hope of understanding the planetary formation processes that built our own solar system.

Discovery News

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