Taken from a distance of about 69 to 64 million miles – just about the distance between the Sun and Venus – the images that make up this animation were captured by the LORRI imaging instrument aboard the New Horizons spacecraft and show its first detection of surface features on Pluto, including what may be the bright reflection of a polar ice cap!
As the ice-encrusted moon Enceladus makes it way along its orbit around Saturn it gets repeatedly squeezed by the giant planet’s gravity, like a frozen stress ball with water-filled insides. This constant squeezing and relaxing generates friction heat in the moon’s crust, which could be responsible for keeping some of its internal water liquid and spraying it out into space from long canyons that cut across its southern pole. And sometimes more ice gets shot out than at other times, forming a trail of long tendrils that stretch into the “E” ring – a hazy, diffuse doughnut around Saturn made from Enceladus’ icy exhaust.
These tendrils had been observed by the Cassini spacecraft since 2006, but only now have they been positively confirmed to be the results of specific geysers on the 318-mile-wide moon.
Scientists have been hunting for evidence of water on Mars ever since we started looking at the Red Planet through telescopes. But Mars does have water, and lots of it; solid water in the form of ice locked up in its polar caps and buried under its surface. And, if observations made by ESA’s Mars Express are indicative of similar processes seen on Earth, these ancient hills may also hold hidden deposits of underground ice.
It’s been thought for some time that Saturn’s largest moon Titan has a complex internal structure consisting of multiple layers of ice and liquid water. At one point it was even suggested that there are water ice “cryovolcanoes” on Titan, where watery slush oozes to the surface and freezes solid in the moon’s 270-degree-below temperatures, in very much the same way that liquid rock does on Earth. Now, thanks to recent gravitational observations by Cassini (and who else?) some researchers think that Titan’s icy shell may be much thicker in places than once thought, making the existence of ice volcanoes and Earthlike plate tectonics much less likely.
Although surface temperatures on Titan are cold enough that methane can exist as a liquid, filling lakes and flowing in streams, it may sometimes get so cold that even the liquid methane and ethane freezes, forming floes and icebergs of frozen hydrocarbons. This Titanic revelation was announced today during the 221st American Astronomical Society meeting in Long Beach, CA.
Who says Mercury’s too hot to be really cool? Even three times closer to the Sun than we are, lacking atmosphere and with scorching daytime temperatures of 425 ºC (800 ºF), Mercury still has places more than cold enough to hide ice. This is the most recent announcement from the MESSENGER mission team: (very nearly) confirmed ice on the first rock from the Sun!