A 'pale blue dot' is the best picture we will get of an Earth-like extrasolar world using even the most advanced telescopes planned for the next couple decades. If we can determine that the planet has oceans of liquid water, it greatly increases the likelihood that it supports life.
The NASA/JPL Epoxi spacecraft fired its engines today to prepare for a Dec. 29 Earth flyby. The Epoxi mission is scheduled to fly past comet Hartley 2 in 2010.
Scientists are using a video of Earth and the Moon taken from 31 million miles away to develop techniques to study alien worlds.
NASA's Deep Impact has been re-christened EPOXI.
A drawing of EPOXI's trajectory.
Deep Impact, now EPOXI, was launched in 2005.
A view of EPOXI's telescope assemblies.