A recently spied planet orbits so close to its star that a new year comes every 10 hours.
Called SWEEPS-10, the planet belongs to a newfound class of zippy exoplanets called ultra-short-period planets (USPPs) that have orbits of less than a day.
The Hubble Space Telescope recently spotted five USPPs, all about the size of Jupiter, in a crowded star field [image] near the galactic bulge of our Milky Way galaxy as part of an exoplanet survey called the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS). A total of 16 planet candidates were found, all with relatively short orbital periods.
"These are the farthest planets detected so far around some of the faintest stars," study leader Kailash Sahu of the Space Telescope Science Institute (STScI) in Maryland told reporters at a NASA press conference.
Extrapolated to the entire Galaxy, the Hubble results suggest the Milky Way contains at least 6 billion Jupiter-sized planets, researchers say.
The findings are detailed in the Oct. 5 issue of the journal Nature.
The new planets were discovered using the transit technique, in which researchers calculate a planet's mass and size based on the periodic dimming of starlight the planet creates when it passes in front of its parent star.
