NASA’s Mars Reconnaissance Orbiter has revealed that movement in sand dune fields on the Red Planet occurs on a surprisingly large scale, about the same as in dune fields on Earth.

This is unexpected because Mars has a much thinner atmosphere than Earth, is only about one percent as dense, and its high-speed winds are less frequent and weaker than Earth’s.

For years, researchers debated whether sand dunes observed on Mars were mostly fossil features related to past climate, rather than currently active. In the past two years, researchers using images from Mars Reconnaissance Orbiter’s High Resolution Imaging Science Experiment (HiRISE) camera have detected and reported sand movement.

CONTINUED at Science Daily.

This is a computer model of a supermassive black hole 2.7-billion light years away sucking the gas off a red giant, based on the recent observations of such an event by astronomers using the Galaxy Evolution Explorer (GALEX) and Pan-STARRS telescope in Hawaii. Why they couldn’t capture ACTUAL video is beyond me, but I suspect it has something to with somebody forgetting to push record.

Astronomers say supermassive black holes rip apart stars very rarely, maybe just once every 10,000 years per galaxy.
“This likely happened when the star went through the red giant phase, where it expanded to 100 times its original radius,” Gezari said. “When it puffed up like that, it became vulnerable to the gravitational tidal forces of the black hole, and it would have been very easy to strip off the tenuous hydrogen envelope.

“However, the star then had to approach much closer, 100 times closer in, before it was completely disrupted by the black hole. We think it approached all the way in to one-third of an astronomical unit, similar to the orbit of Mercury [about one-third the distance between the Earth and sun]. We then saw the helium gas streaming into the black hole.”

Not to brag or anything, but I’ve swallowed stars before. I’ve also been known to eat my fair share of crescent moons. “Lucky Charms marshmallows don’t count.” THE HELL THEY DON’T.

Source: Geekologie.

Strange flying-saucer-shaped moons embedded in Saturn’s rings have baffled scientists studying images transmitted by the ESA’s Cassini Spacecraft. Research suggests that the oddly shaped moons, Pan and Atlas, are born largely from clumps of icy particles in the rings themselves, a discovery that could shed light on how Earth and other planets formerd from the disk of matter that once surrounded our newborn sun.

Observations by NASA’s Cassini spacecraft revealed the moons Atlas and Pan, each roughly 12 miles (20 kilometers) from pole to pole, have massive ridges bulging from their equators some 3.7 to 6.5 miles (6 to 10.5 kilometers) high, giving them the classic Earthly UFO appearance.

At first glance, one could assume that fast rates of spin might have stretched Atlas and Pan out into such unusual shapes, just as tossing a disk of pizza dough flattens it out. But astronomers discovered that each takes about 14 hours to complete a rotation — not nearly fast enough to cause the flattened, disk-like shape.

Carolyn Porco, a planetary scientist at the Space Science Institute in Boulder, Colo., and her colleagues suspected these peculiar moons could be formed mostly from Saturn’s rings, rather than just from fragments produced in collisions of larger moons. The location of the ridges lined up precisely with the rings of icy particles in which they were embedded.

After analyzing the shapes and densities of the moons from data captured by Cassini, Porco’s team found that Pan and Atlas appear to be mostly light, porous, icy bodies, just like the particles making up the rings. Computer simulations suggest one-half to two-thirds of these bizarre moons are made of ring material, piled up on massive, dense fragments of bigger moons that disintegrated billions of years ago after catastrophic collisions with one another.

Astrophysicist Sebastien Charnoz at University of Paris Diderot, the lead author of a related study suggests that the Saturnian ice-clump moons elongated and bulged out into the flying-saucer shapes in the manner of accretion disks, which “are found everywhere in the universe —around black holes, around stars, around Jupiter.”

Charnoz added that understanding how the icy particles piled up to make these shapes could shed light on how matter in the protoplanetary disks of our Solar System that formed around our newborn sun could have clumped together to make planets. …

Source: The Daily Galaxy.

Craters made by asteroid impacts may be the best place to look for signs of life on other planets, a study suggests. Tiny organisms have been discovered thriving deep underneath a site in the US where an asteroid crashed some 35 million years ago.

Scientists believe that the organisms are evidence that such craters provide refuge for microbes, sheltering them from the effects of the changing seasons and events such as global warming or ice ages.

Life forms

The study suggests that crater sites on Mars may also be hiding life, and that drilling beneath them could lead to evidence of similar life forms.

Researchers from the University of Edinburgh drilled almost 2 km below one of the largest asteroid impact craters on Earth, in Chesapeake Bay, US.

Samples from below ground showed that microbes are unevenly spread throughout the rock, suggesting that the environment is continuing to settle 35 million years after impact.

Microbe nutrients

Scientists say that heat from the impact of an asteroid collision would kill everything at the surface.

However, fractures to rocks deep below would enable water and nutrients to flow in and support life.

Some organisms grow by absorbing elements such as iron from rock.

The research was published in the journal Astrobiology.

“The deeply fractured areas around impact craters can provide a safe haven in which microbes can flourish for long periods of time. Our findings suggest that the subsurface of craters on Mars might be a promising place to search for evidence of life,” said Professor Charles Cockell, of the School of Physics and Astronomy. Cockell is first author of the study.

Source: Science Daily.

NASA on Monday cleared a cargo ship owned by Space Exploration Technologies for a test flight to the International Space Station that is scheduled to launch on April 30, NASA officials said.

The Dragon mission would be the first time a privately owned and operated vessel visits the space station, a $100 billion research laboratory owned by the United States, Russia, Europe, Japan and Canada that orbits about 240 miles above Earth.

NASA is counting on Space Exploration Technologies, also known as SpaceX, and a second company, Orbital Sciences Corp., to keep the space station stocked with supplies and science experiments following the retirement of the space shuttles last year. The companies’ combined contracts for cargo deliveries are worth $3.8 billion.

“In order for space station to be successful, these systems have to be there for us,” space station program manager Mike Suffredini said at news conference following a NASA review of the upcoming SpaceX mission.

“We’re really rooting for the teams to come through,” added NASA Associate Administrator Bill Gerstenmaier.

CONTINUED at Yahoo News.

While scientists believe conditions suitable for life might exist on the so-called “super-Earth” in the Gliese 581 system, it’s unlikely to be transferred to other planets within that solar system.

“One of the big scientific questions is how did life get started and how did it spread through the universe,” said Jay Melosh, distinguished professor of earth and atmospheric sciences. “That question used to be limited to just the Earth, but we now know in our solar system there is a lot of exchange that takes place, and it’s quite possible life started on Mars and came to Earth. There’s also been a great deal of discussion about the possible spread of life in the universe from star to star.”

Moon rocks and Mars meteorites have been found on Earth, which led Melosh to previously suggest living microbes could be exchanged among planets in a similar manner.

A Purdue research team has found that, in contrast to our own solar system, the exchange of living microbes between “super-Earth” and planets in that solar system is not likely to occur.

Laci Brock, a student studying interdisciplinary physics and planetary science, and Melosh will present those findings March 20 at the 43rd Lunar and Planetary Science Conference in The Woodlands, Texas.

CONTINUED at Science Daily.

An orbiting Nasa space telescope captured a dark, planet-sized object flying close to the sun on Monday – and extending what looks like a refueling tube into the star’s surface.

The black, Death Star-like, orb is briefly engulfed in light from the sun, then flies off into space.

A video edited from the Solar Dynamics Observatory’s photos inspired a wave of speculation on YouTube.

The imagery was captured by Nasa’s Solar Dynamics Observatory and edited together by a YouTube user, Sunsflare, who challenged experts to explain the strange ‘visitor.’

Naturally, the space agency has a rather more ordinary explanation for the strange, black orb.

It’s not a visitor from another solar system – or a planet being born out of the surface of the sun, as others had speculated.

Instead, it’s a solar ‘prominence’ or ‘filament’ – a feature extending out from the sun which forms over the course of a day, and can extend hundreds of thousands of miles into space.

Scientists are still puzzled as to why these features form. The ‘dark’ parts are material cooler than the surrounding solar matter.

C. Alex Young, a solar astrophysicist at NASA’s Goddard Space Flight Centre said, in a reply to Sunsflare’s video, ‘Filaments appear to be dark because they’re coolerin relation to what’s in the background. When you look at it from the edge of the sun, what you see is this spherical object and you’re actually looking down the tunnel.’

Nasa says, ‘A solar prominence (also known as a filament when viewed against the solar disc) is a large, bright feature extending outward from the Sun’s surface.

‘Prominences are anchored to the Sun’s surface and extend outwards into the Sun’s hot outer atmosphere, called the corona.

‘Scientists are still researching how and why prominences are formed.

‘An erupting prominence occurs when such a structure becomes unstable and bursts outward, releasing the plasma.

Nasa’s Solar Dynamics Observatory frequently captures the phenomenon – although often as violent eruptions, rather than the eerie sphere of this week’s activity.

‘It is not uncommon for prominence material to drain back to the surface as well as escape during an eruption,’ says Holly Gilbert a Goddard solar physicist.

‘Prominences are large structures, so once the magnetic fields supporting the mass are stretched out so that they are more vertical, it allows an easy path for some of the mass to drain back down.’

Source: The Daily Mail.

Two teams of astronomers have used data from NASA’s Chandra X-ray Observatory and other telescopes to map the distribution of dark matter in a galaxy cluster known as Abell 383, which is located about 2.3 billion light years from Earth. Not only were the researchers able to find where the dark matter lies in the two dimensions across the sky, they were also able to determine how the dark matter is distributed along the line of sight.

Dark matter is invisible material that does not emit or absorb any type of light, but is detectable through its gravitational effects. Several lines of evidence indicate that there is about six times as much dark matter as “normal,” or baryonic, matter in the Universe. Understanding the nature of this mysterious matter is one of the outstanding problems in astrophysics.

Galaxy clusters are the largest gravitationally-bound structures in the universe, and play an important role in research on dark matter and cosmology, the study of the structure and evolution of the universe. The use of clusters as dark matter and cosmological probes hinges on scientists’ ability to use objects such as Abell 383 to accurately determine the three-dimensional structures and masses of clusters.

CONTINUED at Science Daily.