I discovered Fomalhaut b on Saturday, May 24, 2008, while working at home in Berkeley, CA. The observations were obtained from two of my programs in 2004 and 2006 using the Advanced Camera for Surveys aboard the Hubble Space Telescope. I confirmed that Fomalhaut b was not an artificial artifact in the data by comparing images obtained at two filters, at separate epochs, at different x,y positions on the detector, and with different angular orientations of the camera on the sky.
Fomalhaut b is comoving (i.e. physically associated) with the star, and shows a small offset between 2004 and 2006 that is expected for Keplerian orbital motion. Analysis of the planet's light and gravitational influence on the dust belt is consistent with a planet mass less than three times that of our Jupiter.
The discovery is the first optical image of a planet around another star, and among the first where orbital motion is directly measured. Images of exoplanets are crucial for future work where a spectrum of its atmosphere will reveal composition, which could include evidence for life.
Please click here to browse through the press release text, photographs, and illustrations from NASA. Click here for the press release from UC Berkeley.