フォーマルハウトb
Fomalhaut b, formally named Dagon (), is a confirmed, directly imaged extrasolar object and candidate planet orbiting the A-type main-sequence star Fomalhaut, approximately 25 light-years away in the constellation of Piscis Austrinus. The object was initially announced in 2008 and confirmed as real in 2012 from images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope and, according to calculations reported in January 2013, has a 1,700-year, highly elliptical orbit. It has a periastron of 7.4 billion km (~50 AU) and an apastron of about 44 billion km (~300 AU). As of May 25, 2013 it is 110 AU from its parent star.