October 26, 2012
Studying Hubble Data Revives a Zombie Exoplanet
A second look at data from NASA’s Hubble Space Telescope is reanimating the claim that the nearby star Fomalhaut hosts a massive exoplanet. The study suggests that the planet, named Fomalhaut b, is a rare and possibly unique object that is completely shrouded by dust.
Fomalhaut is the brightest star in the constellation Piscis Austrinus and lies 25 light-years away.
In November 2008, Hubble astronomers announced the exoplanet, named Fomalhaut b, as the first one ever directly imaged in visible light around another star. The object was imaged just inside a vast ring of debris surrounding but offset from the host star. The planet’s location and mass — about three times Jupiter’s — seemed just right for its gravity to explain the ring’s appearance.
Recent studies have claimed that this planetary interpretation is incorrect. Based on the object’s apparent motion and the lack of an infrared detection by NASA’s Spitzer Space Telescope, they argue that the object is a short-lived dust cloud unrelated to any planet.
A new analysis, however, brings the planet conclusion back to life.