Twin suns aren’t just a phenomenon in a galaxy far, far away. The Hubble telescope recently discovered a new planet about the size of Saturn that orbits around two stars near the center of the Milky Way.
The system, OGLE-2007-BLG-349 (or as I choose to christen it: “New Tatooine”), is 8,000 light-years away from Earth. The planet orbits the stars once every seven years at a distance of around 300 million miles, roughly about as far as it is from our sun to the asteroid belt. The two suns, meanwhile, are only 7 million miles apart.
According to Hubble, astronomers first noticed what they thought to be a planet and a star nine years ago, but they were befuddled by the discovery of a third body.
“The ground-based observations suggested two possible scenarios for the three-body system: a Saturn-mass planet orbiting a close binary star pair or a Saturn-mass and an Earth-mass planet orbiting a single star,” NASA’s David Bennett explained in a press release.
Using the Hubble, however, researchers were recently able to observe that the starlight was too faint to be a typical star like our sun. Instead, the brightness was about what we’d expect from two closely orbiting red dwarf stars. “The model with two stars and one planet is the only one consistent with the Hubble data,” Bennett said.
The discovery marked the first time that scientists have been able to identify a three-body system, as it’s known, using the gravitational microlensing technique. The system is too far away for Hubble to capture any sort of clear image of the relatively small planet and stars. Instead, the telescope was able to detect where the gravity of a foreground star bent and amplified the light of an aligned background star.
Since the new planet is more than three times as far away from its suns as the Earth is from ours, it’s probably not a desert world, and there’s probably not a young farm boy on it gazing out at the sunset and dreaming of a life beyond his aunt and uncle’s farm.