According to the “Extrasolar Planets Encyclopaedia” there are 268 known planets around stars other than our own.

The Advanced Camera for Surveys on the Hubble Space Telescope was used by astronomers to study one of them called HD 189733b. You won’t find any close up images, astronomers used a grism – yes they are a fun lot. A “grism” is a cross between a prism and a diffraction grating. They were looking at the spectrum of the star and planet.

They found, or rather didn’t find the signatures of sodium, potassium and water in places where they had expected to. They did find condensates of iron, silicates and aluminum oxide dust, which as the press release points out is the compounds on Earth the mineral sapphire is made of. Another really cool finding is the possibility of sunspots on the parent star!

So you should read the press release and you can do that by clicking here. When you go there (you will go there and read the article right?) there are other images.

The image shown at the top of the post (Credit: A. Fujii) is a wide field image of the region where HD 189733b is located. The three bright stars you might recognize as the Summer Triangle. Vega (top left), Altair (lower middle), and Deneb (far left) and if you think this is a nice image you should see how nice it looks on your desktop! Choose your desktop size below.

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.
The Space Telescope European Coordinating Facility in Garching near Munich, Germany is responsible for Hubble’s grism mode.

Image credit: ESA, NASA and Frédéric Pont (Geneva University Observatory)