Fomalhaut B - Initial Discovery By Hubble

Initial Discovery By Hubble

The existence of a massive planet orbiting Fomalhaut was first inferred from Hubble observations published in 2005 that resolved the structure of Fomalhaut's massive, cold debris disk (or dust belt/ring). The belt is not centered on the star, and has a sharper inner boundary than would normally be expected. A massive planet on a wide orbit but located interior to this debris ring could clear out parent bodies and dust in its vicinity, leaving the ring appearing to have a sharp inner edge and making it appear offset from the star.

In May 2008, Paul Kalas and James Graham identified Fomalhaut b from Hubble/ACS images taken in 2004 and 2006 at visible wavelengths (i.e. 0.6 and 0.8 µm). NASA released the composite discovery photograph on November 13, 2008, coinciding with the publication of Kalas and Graham's discovery in Science.

Kalas remarked, "It’s a profound and overwhelming experience to lay eyes on a planet never before seen. I nearly had a heart attack at the end of May when I confirmed that Fomalhaut b orbits its parent star." In the image, the bright outer oval band is the dust ring, while the features inside of this band represent noise from scattered starlight.