The plot to the left says that a "hot Jupiter," often referred to as a "roaster" because of the planet's proximity to its home star, contains water vapor.
The full news release on the story is here.
European scientists using the Spitzer Space Telescope observed the planet, called HD 189733b, transit its sun - pass directly between the sun and the observatory - at three different infrared wavelengths, which are represented by the cross hairs in the image. Measurements of the absorbed starlight passing through the planet at those wavelengths matches the signature of water, as shown by the blue line.
This image was released on the new images page at NASA and is courtesy of NASA/JPL-Caltech/ESA/Institute d'Astrophysique de Paris.
Thanks Centauri Dreams for the pointer.