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Earthshine used to test life detection method
...By imagining the Earth as an exoplanet, scientists observing our planet's reflected light on the Moon with ESO's Very Large Telescope have demonstrated a way to detect life on other worlds...
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Solid buckyballs discovered in space
...Astronomers using NASA’s Spitzer Space Telescope have detected a particular type of molecule, given the nickname “buckyball”, in a solid form for the first time...
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Steamy water-world gets the Hubble treatment
...Hubble Space Telescope observations of a 7 Earth-mass planet find an unusual water-rich world swathed in a thick, steamy atmosphere...
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Nile analogue discovered on Saturn's moon Titan
ESA PRESS RELEASE
Posted: 18 December 2012


The international Cassini mission has spotted what appears to be a miniature extraterrestrial version of the Nile River: a river valley on Saturn's moon Titan that stretches more than 400 km from its 'headwaters' to a large sea.


A miniature version of the Nile River, seen on Saturn's moon Titan by the international Cassini mission. The river valley stretches more than 400 km from its 'headwaters' to a large sea, and likely contains hydrocarbons. The image was acquired on 26 September 2012, on Cassini’s 87th close flyby of Titan. The river valley crosses Titan's north polar region and runs into Kraken Mare, one of the three great seas in the high northern latitudes of the moon. See a larger version of the image. Credit: NASA/JPL–Caltech/ASI
 
It is the first time images have revealed a river system this vast and in such high resolution anywhere beyond Earth.

Scientists deduce that the river is filled with liquid because it appears dark along its entire extent in the high-resolution radar image, indicating a smooth surface.

"Though there are some short, local meanders, the relative straightness of the river valley suggests it follows the trace of at least one fault, similar to other large rivers running into the southern margin of this same Titan sea," says Jani Radebaugh, a Cassini radar team associate at Brigham Young University, USA.

"Such faults - fractures in Titan's bedrock - may not imply plate tectonics, like on Earth, but still lead to the opening of basins and perhaps to the formation of the giant seas themselves."

Titan is the only other world we know of that has stable liquid on its surface. While Earth's hydrologic cycle relies on water, Titan's equivalent cycle involves hydrocarbons such as ethane and methane.

Images from Cassini's visible-light cameras in late 2010 revealed regions that darkened after recent rainfall.

Cassini's visual and infrared mapping spectrometer confirmed liquid ethane at a lake in Titan's southern hemisphere known as Ontario Lacus in 2008.

"This radar-imaged river by Cassini provides another fantastic snapshot of a world in motion, which was first hinted at from the images of channels and gullies seen by ESA's Huygens probe as it descended to the moon's surface in 2005," says Nicolas Altobelli, ESA's Cassini Project Scientist.

The Cassini-Huygens mission is a cooperative project of NASA, ESA and ASI, the Italian space agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and ASI, working with team members from the US and several European countries.

Hubble Reborn
Hubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts.
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The Planets
From tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets.
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3D Universe
Witness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D!
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