Astronomers have found the most populous alien solar system yet - and it looks a bit like ours. In a study published this month in Astronomy & Astrophysics, researchers say they have confirmed five new planets orbiting HD 10180, a star located only 127 light-years away in the southern constellation Hydrus. The team made the observations by tracking subtle changes in the wavelengths of the solar system's sun, caused when the planets gravitationally tug on the star. They've also uncovered evidence for two more bodies: a Saturn-sized world and an Earth-sized, rocky world, which, if verified, would have the smallest mass of any extrasolar planet yet found. But don't book spaceship passage just yet. That planet orbits 3 million kilometers from its star, just 1/20th of the distance of Mercury from our sun.

They're not exactly prime real estate, but Martians may have called them home. The craterlike features in this image, taken by NASA's Mars Reconnaissance Orbiter, are not from comet or asteroid impacts. They're small volcanic cones about 250 meters wide, thousands of which dot a northern lowlands region of the red planet called Acidalia Planitia. Scientists analyzing the cones have concluded that their centers are filled with sediments that once harbored water. The muddy layers were ejected from deep under the surface possibly billions of years ago. If so, the team reports in this month's issue of the journal Icarus, the mud could have contained enough organic materials to support primitive forms of life. Even if the sediments turn out to be lifeless, they could reveal more about the planet's chemical and geological history.

It's been a while, but there's a new movie from Simon's Cat.

Something unusual and mysterious has happened to NGC 4696. Located about 150 million light-years away in the constellation Centaurus, the object is an elliptical galaxy. That should mean a previous collision with another galaxy ripped off its spiral arms, stripped away most of its interstellar gas, and condemned it to a slow death. But NGC 4696 has sprouted something never seen on another galaxy: a huge swirl of dust that stretches for tens of thousands of light-years and whips back around like a question mark. Observations by the Hubble Space Telescope released today show another first: filaments of ionized, or charged, hydrogen gas branching from the dust swirl. And views in x-ray light reveal super-powerful jets of matter squirting from the galaxy's central black hole at nearly the speed of light. Together, these features show that NGC 4696 is a galaxy like no other. Astronomers suspect that the filament resulted from some sort of gravitational interaction with another galaxy, possibly a collision.

Credit: Centre National de la Recherche Scientifique

It may be tiny, slimy, and blind, but the human fish has one thing going for it: It's one of the longest-lived animals around. Named for its fleshy color, the popsicle-sized amphibian, also known as the olm (Proteus anguinus) or the cave salamander, can live to be more than 100 and has an average life span of 69 years. That's about three times older than expected for its weight, researchers report online tomorrow in Biology Letters, as larger species tend to live longer. The team suggests that the human fish's unusual life span might be the result of an inactive lifestyle: The creatures don't move around much, and they reproduce only once every 12 years. Although, with looks like that, who could blame them?

What is WWT?

The WorldWide Telescope (WWT) is a Web 2.0 visualization software environment that enables your computer to function as a virtual telescope - bringing together imagery from the world's best ground- and space-based telescopes for the exploration of the universe. WWT blends terabytes of images, information, and stories from multiple sources into a seamless, immersive, rich media experience delivered over the Internet. Students of all ages will feel empowered to explore and understand the cosmos using WWT's simple and powerful user interface.

Discover the Red Planet with WWT | Mars

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By Wulffmorgenthaler.com

Credit: ESO/L. Calcada

Hurricane Katrina would be regarded as a gentle breeze on HD 209458b. The giant planet, located about 150 light-years away in the constellation Pegasus, is a hot Jupiter - nearly as big as our own gas giant, but orbiting very close to its parent star. Like Mercury and our moon, the planet is tidally locked, meaning it always shows the same face to its sun. As a result, HD 209458b's dayside surface temperature never dips below 1000°C, while its night side temperatures are hundreds of degrees cooler. Such a large temperature gradient generates eye-popping wind speeds. How fast? By carefully analyzing the spectra of starlight streaming through its atmosphere when the planet passes in front of its star, researchers report online today in Nature that HD 209458b generates winds of toxic carbon monoxide reaching 7000 kilometers per hour. That's twice as fast as any aircraft has ever flown - not that anyone would want to fly across this world.

Something strange has happened to Mars's polar ice cap. Instead of a uniform, roughly circular blob, like on Earth, the Martian version resembles a pinwheel (left), with dry, spiral troughs separating the ice sheets. There's also Chasma Boreale, the deep, dagger-shaped gouge that cuts across the pinwheel. Scientists had thought that the canyon, which is 2 kilometers deep, was carved by some catastrophic flood in the distant past. Now in two papers published tomorrow in Nature, researchers think they have solved both mysteries. Using a radar survey of the pole (right), which peered under the ice, they conclude that Chasma Boreale wasn't dug out at all. Instead, Martian winds built up the steep, canyon-like walls over millions of years. As for the pinwheel, the team reports that it likewise formed over many millennia, as strong winds pushed apart the dry ice crystals on the surface, much like winds on Earth create sand dunes.

• Archief

• Neighboring Solar System Resembles Ours
  2010-08-25 10:15:43 - 14 views - 0 reacties
  Astronomers have found the most populous alien solar system yet...
• Martian Volcano Mud May Have Hosted Life
  2010-08-24 17:44:26 - 16 views - 0 reacties
  They're not exactly prime real estate, but Martians may have...
• Simon's Cat in 'The Box'
  2010-08-19 17:50:06 - 21 views - 0 reacties
  It's been a while, but there's a new movie from Simon's Cat.
• Rock, paper, scissors
  2010-08-16 08:07:49 - 34 views - 0 reacties
  
• Odd Galaxy Raises Many Questions
  2010-08-13 08:25:41 - 40 views - 0 reacties
  Something unusual and mysterious has happened to NGC 4696....

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