ScienceShot | 18 June 2010
Credit: David Lafrenière et al., The Astrophysical Journal (2010)
Now that's a lonely planet! Astronomers have discovered a world orbiting its star from 50-billion-kilometers away — or nearly 10 times farther out than Pluto is from our sun. The record-breaking orbit takes about 6000 years to complete. How did such a distant planet form? Reporting in an upcoming issue of The Astrophysical Journal, astronomers say the same cloud of dust and gas that gave birth to the star — known as 1RXS JI60929.1-210524 and located about 450 light-years away in the constellation Scorpius — probably split apart, which is what often happens when binary star systems are born. Except that in this case, the fragment was too small to produce anything but a very large, very cold, and extremely isolated planet.