spacetoday.net: No water found on two exoplanets

Posted: Thu, Feb 22, 2007, 8:52 AM ET (1352 GMT)
Hot Jupiter illustration (NASA/JPL-Caltech)

The first spectra of two extrasolar planets taken by NASA's Spitzer Space Telescope revealed, to the surprise of scientists, no sign of water in the atmospheres of two planets. Spitzer took infrared spectra of the exoplanets HD 189733b and HD 209458b, two "hot Jupiters" so named because they are Jupiter-sized gas giants that orbit very close to their stars. Scientists had expected that the planets would have significant amounts of water vapor in their atmospheres, but none was detected by Spitzer. In addition, the data indicated that one of the planets, HD 209458b, might have unusual clouds of silicate particles in its upper atmosphere. Those clouds might be obscuring the presence of water, scientists said. Scientists called this research a "dress rehearsal" for future efforts to look for evidence of life on other planets.