Intergalactic Weather Channel’s cub reporter Timmy Cratchit reports from both the cold icy surface of Europa and its (relatively) warm subterranean sea. Look out for that crevasse Timmy!
Listen here [3:00m]:
Download here [2.8 Mb]: ftp://space.mit.edu/pub/ajb/radiopio/astrofacts_090804_iwc-europa.mp3
What’s the facts:
Europa is Jupiter’s 4th largest moon and the smallest of the Galilean satellites (discovered by Galileo Galilei in 1610), all of which are visible with the aid of a small telescope or binoculars. One of the smoothest and shiniest objects in the Solar System (it reflects 64% of the light striking it), Europa has a surface that is made up mostly of water ice and is essentially free of craters, indicating that it is continually refreshed. It even has a thin atmosphere of oxygen, formed from sputtering of ice from its surface. But the most intriguing part of Europa may be underground, where a deep ocean is believed to exist, heated internally by gravitational tidal forces from Jupiter (the Moon induces similar forces on Earth that give rise to ocean tides). Water breaking through Europa’s surface may explain its overall smoothness and some low-lying features, including “chaos” regions such as Conamara Chaos. Liquid water may be one of the ingredients necessary for life, mitigating the chemical reactions that spawned life on Earth – the only planet with surface water known. Hence, the presence of water in Europa implies life may exist there, perhaps in the form of extremophiles that don’t need sunlight to derive energy. Hopefully Timmy has found a nice extremophile to play with!
Original air date 4 August 2009.