How life might evolve with “exotic” biochemistry and solvents

London, September 18 (ANI): Scientists at a new interdisciplinary research group in Austria are working to uncover how life might evolve with “exotic” biochemistry and solvents, such as sulfuric acid instead of water.

The research group for Alternative Solvents as a Basis for Life Supporting Zones in (Exo-) Planetary Systems was established by the University of Vienna.

Traditionally, planets that might sustain life are looked for in the ‘habitable zone’, the region around a star in which Earth-like planets with carbon dioxide, water vapor and nitrogen atmospheres could maintain liquid water on their surfaces.

Consequently, scientists have been looking for biomarkers produced by extraterrestrial life with metabolisms resembling the terrestrial ones, where water is used as a solvent and the building blocks of life, amino acids, are based on carbon and oxygen.

However, these may not be the only conditions under which life could evolve.

“It is time to make a radical change in our present geocentric mindset for life as we know it on Earth,” said scientist Johannes Leitner.

“Even though this is the only kind of life we know, it cannot be ruled out that life forms have evolved somewhere that neither rely on water nor on a carbon and oxygen based metabolism,” he added.

One requirement for a life-supporting solvent is that it remains liquid over a large temperature range.

Water is liquid between 0 degree Celsius and 100 degrees C, but other solvents exist which are liquid over more than 200 degrees C.

Such a solvent would allow an ocean on a planet closer to the central star.

The reverse scenario is also possible. A liquid ocean of ammonia could exist much further from a star.

Furthermore, sulfuric acid can be found within the cloud layers of Venus and it is now known that lakes of methane/ethane cover parts of the surface of the Saturnian satellite Titan.

Consequently, the discussion on potential life and the best strategies for its detection is ongoing and not only limited to exoplanets and habitable zones.

The newly established research group at the University of Vienna, together with international collaborators, will investigate the properties of a range of solvents other than water, including their abundance in space, thermal and biochemical characteristics as well as their ability to support the origin and evolution of life supporting metabolisms. (ANI)

Cracks on Mars a result of evaporating lakes in ancient times

Washington, September 16 (ANI): Networks of giant polygonal troughs etched across crater basins on Mars have been identified as desiccation cracks caused by evaporating lakes, providing further evidence of a warmer, wetter Martian past.

The findings were presented at the European Planetary Science Congress by PhD student M. Ramy El Maarry of the Max Planck Institute for Solar System Research.

The polygons are formed when long cracks in the surface of the Martian soil intersect.

El Maarry investigated networks of cracks inside 266 impact basins across the surface of Mars and observed polygons reaching up to 250 meters in diameter.

Polygonal troughs have been imaged by several recent missions but, until now, they have been attributed to thermal contractions in the Martian permafrost.

El Maarry created an analytical model to determine the depth and spacing of cracks caused by stresses building up through cooling in the Martian soil.

He found that polygons caused by thermal contraction could have a maximum diameter of only about 65 meters, much smaller than the troughs he was seeing in the craters.

“I got excited when I saw that the crater floor polygons seemed to be too large to be caused by thermal processes. I also saw that they resembled the desiccation cracks that we see on Earth in dried up lakes,” said El Maarry.

“The stresses that build up when liquids evaporate can cause deep cracks and polygons on the scale I was seeing in the craters,” he added.

El Maarry identified the crater floor polygons using images taken by the MOC camera on Mars Global Surveyor and the HiRISE and Context cameras on Mars Reconnaissance Orbiter.

The polygons in El Maarry’s survey had an average diameter of between 70 and 140 kilometers, with the width of the actual cracks ranging between 1 and 10 meters.

Evidence suggests that between 4.6 and 3.8 billion years ago, Mars was covered in significant amounts of water.

Rain and river water would have collected inside impact crater basins, creating lakes that may have existed for several thousand years before drying out.

However, according to El Maarry, in the northern hemisphere, some of the crater floor polygons could have been formed much more recently.

“When a meteorite impacts with the Martian surface, the heat can melt ice trapped beneath the Martian crust and create what we call a hydrothermal system. Liquid water can fill the crater to form a lake, covered in a thick layer of ice. Even under current climatic conditions, this may take many thousands of years to disappear, finally resulting in the desiccation patterns,” said El Maarry. (ANI)

Factors other than trapped ice limit dune movement on Mars

Washington, July 8 (ANI): A study has determined that snow and ice trapped inside dunes on Mars does not entirely stop their movement, a finding which indicates that other factors are limiting the dune movement.

Planetary scientists have monitored some Martian sand dunes for more than 30 years, and the dunes have not moved during that time, leading scientists to question whether snow and ice trapped inside the dunes might be preventing movement.

However, a recent study, led by Mary Bourke, a senior research scientist at the Tucson-based Planetary Science Institute, shows that snow and ice are not enough in themselves to stop dune movement.

While trapped ice and snow impedes movement of sand dunes in polar climates, compared to their counterparts in warmer areas, this does not entirely stop dune movement, the study shows.

“This indicates that other factors are limiting dune movement,” said Bourke.

Bourke also showed that two small dunes recently disappeared on Mars. The dunes, which were 20 meters wide (about 65 feet) and located in the north polar region of Mars, were completely eroded away over a period of 5.7 Earth years.

“This (dune disappearance) is fantastic new data, showing that sand is transported on Mars where and when the wind energy is available,” Bourke said. “But the bigger, larger dunes on Mars are not moving, at least in the areas we studied,” she added.

In the most recent study, Bourke and her colleagues used vertical aerial photos and LiDAR (Light Detection and Ranging) data to estimate dune migration rates in Antarctica’s Victoria Valley dune field.

The photos, taken between 1961 and 2001, came from the USGS Antarctic Resource Center.

These dunes are known to be covered by seasonal snowfalls and have snow and ice layers trapped inside.

Bourke found that the dunes migrated about 1.5 meters (5 feet) per year, which is small compared to the distance covered by dunes in warm deserts, which can be as high as 30-70 meters (about 100 to 230 feet) a year.

Factors limiting dune movement on Mars would include the planet’s thin atmosphere, which requires very high wind speeds to provide the force needed to move sand, and the water and carbon-dioxide frosts that cover dunes in Mars’ polar regions for 70 percent of the year. (ANI)

Martian climate was life-friendly more recently than thought

Washington, July 1 (ANI): In a new research, scientists have found evidence that indicates the Martian climate was life-friendly more recently than thought.

Matthew Balme, a research scientist with the Tucson-based Planetary Science Institute and a research fellow at the United Kingdom’s Open University, discovered signs of melting permafrost in images from NASA’s HiRISE (High Resolution Imaging Science Experiment) camera, which is flying aboard the Mars Reconnaissance Orbiter.

The images show that landforms once thought to be shaped by volcanism were actually modified by the expansion and contraction of ice due to freeze/thaw cycles, according to Balme.

Balme studied an outflow channel that was active as recently as 2 to 8 million years ago.

The channel contains polygonal patterns, branched channels, blocky debris and mound/cone formations, all of which are similar to formations found where permafrost melts on Earth.

“These observations demonstrate that ice melted near the Martian equator within the past few million years and then refroze,” Balme said. “This probably happened over many freeze/thaw cycles,” he added.

Since liquid water is essential to life as we know it, this equatorial channel would be an ideal place to hunt for traces of past or present Martian life, Balme added. (ANI)

Ancient Mars lake may have held as much water as Lake Champlain in US

Washington, June 20 (ANI): Scientists have found evidence of the remnants of an ancient lake nestled in a valley near the Martian equator, which may have held as much water as Lake Champlain.

According to a report in Disocvery News, the evidence was found by Gaetano di Achille and a team of researchers at the University of Colorado in Boulder, US, in the form of an ancient shoreline ringing Shalbatana Vallis, a gash in Mars’ surface just east of the massive volcanic province, Tharsis Rise.

Though dry and frigid now, the traces it left behind hint at a water body younger than any other on the planet, and its sediments are a prime target for finding fossilized alien life.

When Mars coalesced billions of years ago it was much warmer, and probably wet. Features that appear to be eroded river deltas more than 3.7 billion years old dot parts of the planet’s surface.

Researchers have speculated they are evidence of lakes – and primitive life may have once existed on the surface.

Now, Gaetano’s team of researchers estimated from powerful images obtained using the powerful High Resolution Imaging Science Experiment (HiRISE) camera on board the Mars Reconnaissance Orbiter (MRO), that the ancient lake was 450 meters (1,476 feet) deep and nearly identical in volume to Lake Champlain in Vermont.

Even more intriguingly, it dried up around 3.4 billion years ago – 300 million years after the Red Planet’s “warm and wet” phase is thought to have ended.

Its deltas appear rich in fine-grained sediments, a sign that they have been relatively untouched by erosion.

“Deltas are high priority targets for exploration because they imply copious and long-lived water,” team member Brian Hynek of the University of Colorado in Boulder told Discovery News. “And the sedimentation process is very effective at burying and preserving organic material,” he said.

The lake is a tempting place to look for fossilized alien life forms.

“Life wouldn’t have arisen in this lake, but lakes on Earth provide many habitats for countless organisms,” said Patrick McGovern of the Lunar and Planetary Institute in Houston.

“This lake could have helped sustain and proliferate life on Mars, if it ever arose,” he added. (ANI)

NASA selects future projects to study Mars and Mercury

Washington, May 5 (ANI): NASA has selected two science investigations that will aid in the interior examination of Mars and probe the tenuous atmosphere of Mercury.

The projects, valued at approximately 38 million dollars, also establish new alliances with the European Space Agency, or ESA.

“The selections will further advance our knowledge of these exciting terrestrial planets,” said Jim Green, director of NASA’s Planetary Division at NASA Headquarters in Washington.

“The international collaboration will create a new chapter in planetary science and provide a strong partnership with the international science community to complement future robotic and human exploration activities,” he added.

The Lander Radio-Science on ExoMars, or LaRa, will use NASA’s Deep Space Network of radio telescopes to track part of ESA’s ExoMars mission.

Scheduled to launch in 2016, the mission consists of a fixed lander and a rover that will roam Mars collecting soil samples for detailed analysis.

Data relayed from the lander back to the network will allow scientists to measure and analyze variations in the length of the day and location of the planet’s rotational axis.

This data will help researchers further dissect the structure of the Red Planet’s interior, including the size of its core.

When combined with the lander’s onboard instruments, the data also may help confirm whether the planet’s interior is still, at least partially, composed of liquid.

The second selection, named Strofio, will employ a unique mass spectrometer.

The instrument will determine the mass of atoms and molecules to reveal the composition of Mercury’s atmosphere.

The investigation will study the atmosphere, which is formed from material ejected from its surface, to reveal the composition of Mercury’s surface.

Strofio will investigate Mercury as a key component of the Italian Space Agency’s suite of science instruments that will fly aboard ESA’s BepiColombo mission.

Scheduled for launch in 2013, the mission is composed of two spacecraft.

Japan will build one spacecraft to study the planet’s magnetic field. ESA will build the other to study Mercury directly. (ANI)

Comets may have provided key ingredients for life on Earth

Tel Aviv, April 29 (ANI): A new study by researchers at Tel Aviv University in Israel has suggested that comets might have provided the elements for the emergence of life on our planet.

While investigating the chemical make-up of comets, Professor Akiva Bar-Nun of the Department of Geophysics and Planetary Sciences at Tel Aviv University found they were the source of missing ingredients needed for life in Earth’s ancient primordial soup.

“When comets slammed into the Earth through the atmosphere about four billion years ago, they delivered a payload of organic materials to the young Earth, adding materials that combined with Earth’s own large reservoir of organics and led to the emergence of life,” said Professor Bar-Nun.

It was the chemical composition of comets that allowed them to kickstart life, he added.

Using a one-of-a-kind machine built at Tel Aviv University, researchers were able to simulate comet ice, and found that comets contain ingredients necessary for providing the basic nutrients of life.

Specifically, Prof. Bar-Nun looked at the noble gases Argon, Krypton and Xenon, because they do not interact with any other elements and are not destroyed by Earth’s oxygen.

These elements have maintained stable proportions in the Earth’s atmosphere throughout the lifetime of the planet, he explained.

“Now, if we look at these elements in the atmosphere of the Earth and in meteorites, we see that neither is identical to the ratio in the sun’s composition. Moreover, the ratios in the atmosphere are vastly different than the ratios in meteorites which make up the bulk of the Earth,” said Bar-Nun.

“So we need another source of noble gases which, when added to these meteorites or asteroid influx, could change the ratio. And this came from comets,” he added.

During the comets’ formation, the porous ice trapped gases and organic chemicals that were present in outer space.

“The pattern of trapping of noble gases in the ice gives a certain ratio of Argon to Krypton to Xenon, and this ratio – together with the ratio of gases that come from rocky bodies – gives us the ratio that we observe in the atmosphere of the Earth,” said Bar-Nun.

Thus, the arrival on Earth of comets and asteroids led to the necessary ratio of materials for organic life, “which eventually were dissolved in the ocean and started the long process leading to the emergence of life on Earth,” he added. (ANI)

Cyclones can feed global warming by spurting ice into stratosphere

Washington, April 21 (ANI): Scientists at Harvard University, US, have found that tropical cyclones readily inject ice far into the stratosphere, possibly feeding global warming.

The finding provides more evidence of the intertwining of severe weather and global warming by demonstrating a mechanism by which storms could drive climate change.

Many scientists now believe that global warming, in turn, is likely to increase the severity of tropical cyclones.

“Since water vapor is an important greenhouse gas, an increase of water vapor in the stratosphere would warm the Earth’s surface,” said David M. Romps, a research associate in Harvard’s Department of Earth and Planetary Science.

“Our finding that tropical cyclones are responsible for many of the clouds in the stratosphere opens up the possibility that these storms could affect global climate, in addition to the oft-mentioned possibility of climate change affecting the frequency and intensity of tropical cyclones,” he added.

Romps and co-author Zhiming Kuang, assistant professor of climate science in Harvard’s Faculty of Arts and Sciences, were intrigued by earlier data suggesting that the amount of water vapor in the stratosphere has grown by roughly 50 percent over the past 50 years.

Scientists are currently unsure why this increase has occurred.

The Harvard researchers sought to examine the possibility that tropical cyclones might have contributed by sending a large fraction of their clouds into the stratosphere.

Using infrared satellite data gathered from 1983 to 2006, Romps and Kuang analyzed towering cloud tops associated with thousands of tropical cyclones, many of them near the Philippines, Mexico, and Central America.

Their analysis demonstrated that in a cyclone, narrow plumes of miles-tall storm clouds can rise so explosively through the atmosphere that they often push into the stratosphere.

Romps and Kuang found that tropical cyclones are twice as likely as other storms to punch into the normally cloud-free stratosphere, and four times as likely to inject ice deep into the stratosphere.

According to the researchers, if very deep clouds, such as those in a tropical cyclone that can rise through the atmosphere at speeds of up to 40 miles per hour, can punch through the tropopause, they can deposit their ice in the warmer overlying stratosphere, where it then evaporates.

“This suggests that tropical cyclones could play an important role in setting the humidity of the stratosphere,” said Romps and Kuang. (ANI)

“Noise” from space may help reveal mass of near-Earth asteroids

Washington, April 4 (ANI): Planetary scientists are all set to turn “noise” from the data obtained by NASA/ESA LISA satellites’ mission into useful information about the mass of near-Earth asteroids.

LISA is on a mission to detect gravitational waves – a warping of the space/time continuum that scientists hope to see directly for the first time.

Slated for launch no earlier than 2018, LISA will include three satellites connected by laser beams. The distance between the satellites should change as a gravitational wave passes.

Einstein’s General Theory of Relativity predicts that gravitational waves from exploding stars or colliding black holes ripple across the universe, causing other bodies to wobble like driftwood in a motorboat’s wake.

In 2006, planetary scientists realized that Near Earth Asteroids (NEAs) also would make the spacecraft wobble as they passed nearby, creating a distinct signature in the data being collected.

Pasquale Tricarico, a scientist at the Tucson-based Planetary Science Institute, expanded on that work to predict the number of asteroid encounters LISA can expect and how those encounters can be used to determine the mass of passing asteroids.

According to Tricarico, LISA can expect to see one or two known near-Earth asteroids a year, and a total of around ten during the expected mission lifetime.

When an encounter with a known asteroid shows up in the data, scientists will already know its trajectory.

“So from the signal, we can indirectly measure the asteroid’s mass because that’s the only uncertainty in the equation,” Tricarico said.

“These mass measurements are important because we only know the mass of asteroids that have been visited by spacecraft or the mass of a few binary asteroids observed from Earth,” he added.

“We always wonder about the porosity, the density, and this will give us measurements from additional asteroids,” he explained.

If a known asteroid passes one of the satellites and doesn’t leave a signature, “that allows us to put an upper limit on the mass of that asteroid,” Tricarico added.

Tricarico also has predicted the number of potential encounters with smaller, unknown NEAs.

If LISA starts detecting five asteroids a year instead of two or three, this could modify theories concerning the distribution of sizes in the NEA population. (ANI)

Hubble captures quadruple Saturn moon transit

Washington, March 18 (ANI): The Hubble Space Telescope has taken a photo of four moons of Saturn passing in front of their parent planet, in a rare moon transit.

In this view, the giant orange moon Titan casts a large shadow onto Saturn’s north polar hood.

Below Titan, near the ring plane and to the left is the moon Mimas, casting a much smaller shadow onto Saturn’s equatorial cloud tops.

Titan, Saturn’s largest moon, crossed Saturn on four separate occasions: January 24, February 9, February 24, and March 12, although not all events were visible from all locations on Earth.

Farther to the left, and off Saturn’s disk, are the bright moon Dione and the fainter moon Enceladus.

These rare moon transits only happen when the tilt of Saturn’s ring plane is nearly “edge on” as seen from the Earth.

The latest pictures were taken with Hubble’s Wide Field Planetary Camera 2 on February 24, 2009, when Saturn was at a distance of roughly 775 million miles (1.25 billion kilometers) from Earth.

Hubble can see details as small as 190 miles (300 km) across on Saturn.

The dark band running across the face of the planet slightly above the rings is the shadow of the rings cast on the planet.

Saturn’s rings will be perfectly edge on to our line of sight on August 10, 2009, and September 4, 2009. Unfortunately, Saturn will be too close to the Sun to be seen by viewers on Earth at that time.

This “ring plane crossing” occurs every 14-15 years.

In 1995-96, Hubble witnessed the ring plane crossing event, as well as many moon transits, and even helped discover several new moons of Saturn.

The banded structure in Saturn’s atmosphere is similar to Jupiter’s.

Early 2009 was a favorable time for viewers with small telescopes to watch moon and shadow transits crossing the face of Saturn. (ANI)

Water and life may be present beneath Martian volcano

Washington, March 5 (ANI): A team of scientists has used a computer modeling system to reach the surprising conclusion that pockets of ancient water may still be trapped under the Martian volcano Olympus Mons, that has implications for life on the Red Planet.

The computer model was developed by Rice University professors Patrick McGovern and Julia Morgan.

The scientists explained that their finding is more implication than revelation.

“What we were analyzing was the structure of Olympus Mons, why it’s shaped the way it is,” said McGovern, an adjunct assistant professor of Earth science and staff scientist at the NASA-affiliated Lunar and Planetary Institute. “What we found has implications for life,” he added.

In modeling the formation of Olympus Mons with an algorithm known as particle dynamics simulation, McGovern and Morgan determined that only the presence of ancient clay sediments could account for the volcano’s asymmetric shape.

The presence of sediment indicates water was or is involved.

Olympus Mons is tall, standing almost 15 miles high, and slopes gently from the foothills to the caldera, a distance of more than 150 miles.

That shallow slope is a clue to what lies beneath, according to the researchers.

They suspect if they were able to stand on the northwest side of Olympus Mons and start digging, they’d eventually find clay sediment deposited there billions of years ago, before the mountain was even a molehill.

The European Space Agency’s Mars Express spacecraft has in recent years found abundant evidence of clay on Mars.

This supports a previous theory that where Olympus Mons now stands, a layer of sediment once rested that may have been hundreds of meters thick.

Morgan and McGovern show in their computer models that volcanic material was able to spread to Olympus-sized proportions because of the clay’s friction-reducing effect, a phenomenon also seen at volcanoes in Hawaii.

According to the researchers, what may be trapped underneath is of great interest.

Fluids embedded in an impermeable, pressurized layer of clay sediment would allow the kind of slipping motion that would account for Olympus Mons’ spread-out northeast flank – and they may still be there.

Thanks to NASA’s Phoenix lander, which scratched through the surface to find ice underneath the red dust last year, scientists now know there’s water on Mars.

So, Morgan and McGovern feel it’s reasonable to suspect water may be trapped in pores in the sediment underneath the mountain.

“This deep reservoir, warmed by geothermal gradients and magmatic heat and protected from adverse surface conditions, would be a favored environment for the development and maintenance of thermophilic organisms,” they said. (ANI)

NASA and Cisco develop online platform to monitor global environmental conditions

Washington, March 4 (ANI): NASA and Cisco Inc. have announced a partnership to develop an online collaborative global monitoring platform called the “Planetary Skin” to capture, collect, analyze and report data on environmental conditions around the world.

Under the terms of a Space Act Agreement, NASA and Cisco will work together to develop the Planetary Skin as an online collaborative platform to capture and analyze data from satellite, airborne, sea- and land-based sensors across the globe.

This data will be made available for the general public, governments and businesses to measure, report and verify environmental data in near-real-time to help detect and adapt to global climate change.

“In the past 50 years, NASA’s expertise has been applied to solving humanity’s challenges, including playing a part in discovering global climate change,” said S. Pete Worden, director of NASA’s Ames Research Center.

“The NASA-Cisco partnership brings together two world-class organizations that are well equipped with the technologies and skills to develop and prototype the Planetary Skin infrastructure,” he added.

Cisco and NASA will kick off Planetary Skin with a series of pilot projects, including “Rainforest Skin,” which will be prototyped during the next year.

Rainforest Skin will focus on the deforestation of rainforests around the world and explore how to integrate a comprehensive sensor network.

It also will examine how to capture, analyze and present information about the changes in the amount of carbon in rainforests in a transparent and useable way.

According to scientists, the destruction of rainforests causes more carbon to be added to the atmosphere and remain there. That contributes significantly to global warming.

“Mitigating the impacts of climate change is critical to the world’s economic and social stability,” said John Chambers, Cisco chief executive officer.

“This unique partnership taps the power and innovation of the market and harnesses it for the public good. Cisco is proud to work with NASA on this initiative and hopes others from the public and private sectors will join us in this exciting endeavor,” he added.

Planetary Skin participants will pool their unique skills, assets and technologies to develop the decision support capabilities to effectively manage natural resources such as biomass, water, land and energy; climate change-related risks such as a rise in sea level, droughts and disease proliferation; and new environmental markets for carbon, water and biodiversity. (ANI)

Gullies on Mars show water ran on Red Planet as early as 1.25 mln yrs ago

Washington, March 3 (ANI): Planetary geologists at Brown University, US, have found a gully fan system on Mars that formed about 1.25 million years ago, which shows tantalizing signs of recent water activity on the Red Planet.

The fan offers compelling evidence that it was formed by melt water that originated in nearby snow and ice deposits and may stand as the most recent period when water flowed on the planet.

Gullies are known to be young surface features on Mars. But, scientists studying the planet have struggled with locating gullies they can conclusively date.

In a research paper that appears on the cover of the March issue of Geology, the Brown geologists were able to date the gully system and hypothesize what water was doing there.

The gully system is located on the inside of a crater in Promethei Terra, an area of cratered highlands in the southern mid-latitudes.

The eastern and western channels of the gully each run less than a kilometer from their alcove sources to the fan deposit.

Viewed from afar, the fan appears as one entity several hundred meters wide. But, by zooming in with the HiRISE camera aboard the Mars Reconnaissance Orbiter, Schon was able to distinguish four individual lobes in the fan, and determine that each lobe was deposited separately.

“The gully system shows four intervals where water-borne sediments were carried down the steep slopes of nearby alcoves and deposited in alluvial fans,” said Samuel Schon, a Brown graduate student and the paper’s lead author.

However, the finding of a gully system, even an isolated one, that supported running water as recently as 1.25 million years ago greatly extends the time that water may have been active on Mars.

It also adds to evidence of a recent ice age on the planet when polar ice is believed to have been transported towards the equator and settled in mid-latitude deposits, according to James Head III, professor of geological sciences at Brown University, who first approximated the span of the Martian ice age in a Nature paper in 2003.

“We think there was recent water on Mars,” said Head, who with Brown postdoctoral researcher Caleb Fassett is a contributing author on the paper. “This is a big step in the direction to proving that,” he added.

The team determined that ice and snow deposits formed in the alcoves at a time when Mars had a high obliquity (its most recent ice age) and ice was accumulating in the mid-latitude regions. (ANI)

Could mythical “sprites” be mysterious UFOs?

Washington, Feb 24 (ANI): Scientists at Tel Aviv University in Israel have discovered mysterious flashes, named “sprites”, zipping across the atmosphere, which may well provide a possible explanation for the sightings of UFOs (Unidentified Flying Objects).

In legend, sprites are trolls, elves and other spirits that dance high above our ozone layer.

But, scientists at Tel Aviv University have discovered that some very real “sprites” are zipping across the atmosphere as well, providing a possible explanation for those other legendary denizens of the skies, UFOs.

According to Professor Colin Price, head of the Geophysics and Planetary Sciences Department at Tel Aviv University, thunderstorms are the catalyst for a newly discovered natural phenomenon he calls “sprites.”

He and his colleagues are one of the leading teams in the world studying the phenomenon, and Professor Price leads the study of “winter sprites” ? those that appear only in the northern hemisphere’s winter months.

“Sprites appear above most thunderstorms, but we didn’t see them until recently. They are high in the sky and last for only a fraction of a second,” explained Professor Price.

While there is much debate over the cause or function of these mysterious flashes in the sky, they may explain some bizarre reports of UFO sightings, he added.

Sprites are described as flashes high in the atmosphere, between 35 and 80 miles from the ground, much higher than the 7 to 10 miles where regular lightning bolts usually occur.

“Lightning from the thunderstorm excites the electric field above, producing a flash of light called a sprite,” explained Prof. Price. “We now understand that only a specific type of lightning is the trigger that initiates sprites aloft,” he added.

Though sprites have existed for millions of years, they were first discovered and documented only by accident in 1989 when a researcher studying stars was calibrating a camera pointed at the distant atmosphere where sprites occur.

“Sprites, which only occur in conjunction with thunderstorms, never occur on their own, and are cousins to similar natural phenomenon dubbed by atmospheric electricians as ‘elves’, ‘goblins’ and ‘trolls’,” Prof. Price said.

These flashes are so named because they appear to “dance” in the sky, which may explain some UFO sightings. (ANI)

Scientists unveil first gravity map of moon’s far side

London, Feb 16 (ANI): The first detailed map of the gravity fields on the Moon’s far side has shown that craters there are different than those on the near side, which could reveal more about the Moon as it was billions of years ago, when magma flowed across its surface.

According to a report in New Scientist, the new gravity map was collected by the Japanese lunar satellite Kaguya, which released two small probes into orbit around the Moon in 2007.

The motions of the three spacecraft, which are sensitive to variations in the Moon’s gravity field, were measured by tracking their radio signals.

Crucially, while the main Kaguya spacecraft was on the far side of the Moon and therefore out of direct contact with Earth, one of the small probes relayed its signals to Earth.

The resulting map, which is the first detailed one completed of the Moon’s far side, shows that craters on the far side have a markedly different gravity signature from those on the side that always faces Earth.

That suggests that billions of years ago, there might have been large differences in the temperature or thickness of the Moon’s two halves.

“It’s fabulous new data,” said Walter Kiefer, a planetary geophysicist with the Lunar and Planetary Institute in Houston, Texas, who was not part of the study. “We haven’t been able to get a good look at the far side until now,” he added.

Most of the large craters on the Moon formed more than 3.8 billion years ago. These were partly filled in by magma that flowed on the surface before the Moon cooled and its geological activity died down.

But, a number of craters also seem to have been filled in from below.

Researchers believe material from the mantle also rose up in craters, since these are sites where impacts had thinned the Moon’s crust.

The new Kaguya measurements reveal some craters on the far side that seem to have been filled only with mantle.

These craters have higher-than-normal gravity at the centre, surrounded by a thick ring of low gravity that closely matches the original low elevation of the crater.

It is not yet clear what these new crater measurements suggest about the early Moon.

In order for these structures to survive, the lunar far side must have been too cool and stiff to allow the mantle at the craters’ centres to smooth out much over time, according to team leader Noriyuki Namiki, of Japan’s Kyushu University.

“The surface had to be very rigid to support these structures,” Namiki said. (ANI)

Water has played large role in shaping Martian landscape

Washington, Feb 6 (ANI): In a new research, scientists have determined that geologic features in Martian craters suggest deposition and flow of water and ice, which is further evidence for the large role that water has likely played in shaping the landscape of the Red Planet.

The research was done by scientists at the Tucson-based Planetary Science Institute (PSI) in the US.

Their results provide strong evidence that multiple wet and/or icy climate cycles have shaped the topography of the planet’s large craters.

“Studying crater degradation in potentially ice-rich environments is vital to understanding the geology of craters and their surroundings, as well as for determining whether the ice comes from the atmosphere or from below the ground,” said Daniel Berman, a PSI associate research scientist and lead author of the research paper.

Berman, along with PSI Senior Scientist David Crown and PSI Research Scientist Leslie Bleamaster III, surveyed the geologic features in two sets of mid-latitude craters.

Each set included about 100 craters, with the first set in the Arabia Terra region of the northern hemisphere and the second set in an area east of Hellas basin in the southern hemisphere.

The researchers selected craters that are greater than 20 km (about 12.5 miles) in diameter that have been completely or nearly completely photographed by cameras on various spacecraft, including the Mars Odyssey THEMIS VIS camera, the Mars Global Surveyor Mars Orbiter Camera, and the Viking Orbiter cameras.

They looked specifically for the following erosional or depositional features, the number and sizes of those features, and how the features are oriented.

Berman found that lobate flows, gullies, and arcuate ridges on the crater walls between latitudes of 30 to 45 degrees face the pole in their hemisphere, whereas equator-facing orientations are more common than pole-facing ones at latitudes between 45 and 60 degrees.

In the southern study area, narrow channels generally had pole-facing orientations, whereas wider valleys generally have equator-facing orientations.

The features’ pole-facing or equator-facing orientations could result from uneven heating of the crater walls.

Ice on walls that get more sunlight would melt faster, causing more water to flow and form the gullies and other features.

Further evidence for flowing ice is found on the crater floors, Berman observed. He found that the floors of small craters slope away from the walls that exhibit erosional/depositional features toward the more pristine ones.

These slopes have inclines of about 0.5 to 3 degrees. This suggests that ice-rich materials flowed from one crater wall to the other. (ANI)

Global warming has caused Earth’s seasons to arrive 2 days earlier

Washington, Jan 22 (ANI): A new study has brought to the fore another adverse effect of global warming, suggesting that it has led to Earth’s seasons to arrive 2 days earlier than before.

The study, by scientists from the University of California, Berkeley, and Harvard University, has determined that not only has the average global temperature increased in the past 50 years, but the hottest day of the year has shifted nearly two days earlier.

Just as human-generated greenhouse gases appear to the be the cause of global warming, human activity may also be the cause of the shift in the cycle of seasons, according to Alexander R. Stine, a graduate student in UC Berkeley’s Department of Earth and Planetary Science and first author of the report.

Stine and his team based their study on a publicly available database of global surface temperature measurements over both land and ocean from 1850 to 2007 that was compiled by the University of East Anglia’s Climate Research Unit in the United Kingdom.

Using non-tropical data only, the team found that, while land temperatures in the 100-year period between 1850 and 1950 showed a simple pattern of variability, with the hottest day of the year in the Northern Hemisphere around July 21, temperatures in the period 1954-2007 peaked 1.7 days earlier.

Although the cause of this seasonal shift, which has occurred over land, but not the ocean, is unclear, the researchers said that the shift appears to be related, in part, to a particular pattern of winds that also has been changing over the same time period.

This pattern of atmospheric circulation, known as the Northern Annular Mode, is the most important wind pattern for controlling why one winter in the Northern Hemisphere is different from another.

The researchers found that the mode also is important in controlling the arrival of the seasons each year.

According to Stine, whatever the cause, current Intergovernmental Panel on Climate Change (IPCC) models do not predict this phase shift in the annual temperature cycle.

Temperatures at any given time of the year can be very different on land than over the ocean, and a change in the strength and direction of the winds can move a lot of heat from the ocean onto land, which may affect the timing of the seasons, he added.

“However, this seems to be only a partial explanation, because the relationship between this pattern of circulation and the shift in the timing of the seasons is not strong enough to explain the magnitude of the seasonal shift,” said Stine. (ANI)