Hot, Dry, and Cloudy (Artist Concept) This artist's concept
animation shows a cloudy Jupiter-like planet that orbits very
close to its fiery hot star. NASA's Spitzer Space Telescope was
recently used to capture spectra, or molecular fingerprints, of
two "hot Jupiter" worlds like the one depicted here. This is the
first time a spectrum has ever been obtained for an exoplanet,
or a planet beyond our solar system. The ground-breaking
observations were made with Spitzer's spectrograph, which pries
apart infrared light into its basic wavelengths, revealing the
"fingerprints" of molecules imprinted inside. Spitzer studied
two planets, HD 209458b and HD 189733b, both of which were
found, surprisingly, to have no water in the tops of their
atmospheres. The results suggest that the hot planets are socked
in with dry, high clouds, which are obscuring water that lies
underneath. In addition, HD209458b showed hints of silicates,
suggesting that the high clouds on that planet contain very fine
sand-like particles. Capturi