When it launches in 2009, NASA's Kepler Mission will include the most sensitive detection system ever put into service for discovering exosolar planets. In the meantime, our toolkit on Earth is getting better with each passing year. Astronomers using the High Accuracy Radial velocity Planet Searcher (HARPS) at La Silla Observatory in Chile have discovered three new rocky planets orbiting a single star, all within ten times the size of Earth.

ESA astronomers announced this week that they've discovered two more exoplanets, or planets outside our solar system, using the space-based COROT observatory. The two new finds are Jupiter-sized gas giants that orbit close to their parent stars.

But the astronomers also reported that COROT has picked up another object that they can't quite explain. This space oddity, COROT-exo-3b, looks to lie somewhere between a brown dwarf and a planet. It may even be a star, though if that's the case, scientists say it would be among the smallest ever detected.

Everyone seems to be double-extra-cautiously optimistic about this finding, so dont go running out to your telescope tonight looking for greetings from friendly space creatures.

But in work reported today in Nature, astronomers say they used the Hubble Space Telescopes infrared imager to pick up signs of methane in the atmosphere of a Jupiter-sized planet orbiting a star some 63 million light years from Earth. And methane, an organic molecule, is an indicator of the possible presence of life.