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Astronomy
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Earlier this year, the international Cassini spacecraft orbiting Saturn caused a stir when it spied what appeared to be Yellowstone-style geysers spouting from the south pole of Enceladus. Scientists speculated the eruptions were driven by shallow pools of water lurking just below the icy surface. But other researchers propose that buried ice clathrates -- not liquid water -- are responsible for releasing the towering plumes through a sudden tectonic shift in the crust that causes cracks in the ice and gas to vent.
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A robotic probe designed to draw an underwater three-dimensional map showing the biological and geochemical composition of an ice-bound Antarctica lake may prove to be the ideal tool to search for life on other planets or moons where ice is known to exist.
The probe that will map Antarctica's West Lake Bonney, a two-and-a-half mile long, one-mile wide, 130 foot-deep lake located in the continent's McMurdo Dry Valleys. Bonney lies perpetually trapped beneath 12 to 15 feet of ice.
"Our goal is to build a submersible autonomous underwater vehicle to map in 3-D the geochemistry and biology of this ice-covered lake.
NASA is interested in the project because a modified version of the vehicle may be used to probe beneath subglacial ice and look for signs of life, past or present on Jupiter's Europa, which essentially is an ice-covered ocean.
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Craters come in all shapes and sizes, some more bizarre than others. Recent photos of Mercury have revealed two new categories of crater that scientists are puzzling over how to explain.
When NASA's Messenger spacecraft flew by the planet Jan. 14 it snapped pictures of several craters with strange dark halos and one crater with a spectacularly shiny bottom.
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Evidence is mounting: the next solar cycle is going to be a big one. Solar cycle 24, due to peak in 2010 or 2011 "looks like its going to be one of the most intense cycles since record-keeping began almost 400 years ago." "When a gust of solar wind hits Earth's magnetic field, the impact causes the magnetic field to shake. If it shakes hard enough, we call it a geomagnetic storm." In the extreme, these storms cause power outages and make compass needles swing in the wrong direction. Auroras are a beautiful side-effect.
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Rings are not just for planets anymore – astronomers have found them around Saturn's moon Rhea, the first ever observed around a moon.
"It is a huge surprise – we didn't have any suspicions at all"
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Microsoft Research has released a tool in the astronomy field, that does what Google Earth does for geography. Microsoft's World Wide Telescope is a new web-based application that can present information from dozens of different sources to allow you to view the night sky.
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No other 310-mile-wide ice ball in the solar system is attracting quite the attention as Enceladus, a moon of Saturn.
NASA’s Cassini spacecraft had a deliberate near-miss with Enceladus on Wednesday afternoon, passing about 30 miles above its surface at a speed of more than 32,000 miles per hour. Over the next couple of years, Cassini is to swing by another seven times, scrutinizing this little moon more than all of the 50-odd others circling Saturn, except perhaps Titan.
Then again, no other 310-mile-wide ice-ball moon in the solar system has a geyser of icy particles shooting out of its south pole.
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European Southern Observatory (ESO) astronomers have been able to create an "artificial star", 90 km high in the atmosphere, using a laser beam. This "star" can be put at any point in the sky, and it enables the adaptive optics of the VLT telescope to be used throughout the visible sky. Until now, adaptive optics required the light of a strong natural star as a reference - as of now, the artificial star will take this over. The new technology therefore enlarges the field of vision of the most powerful telescope on Earth, to hitherto inaccessible regions.
Video, 4 min 54 sec
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