Confirmed. The NASA / ESA Hubble Space Telescope has been able to confirm, using the gravitational microlensing technique, the presence of a planet orbiting not one, but two red dwarf stars, just like the fictional planet Tatooine from the Star Wars Universe. All three objects were first discovered in 2007.
The planet is 8,000 light years away towards the center of the Milky Way and orbits this stellar duo 450 million kilometers from them, so it takes about 7 Earth years to make a complete revolution, something like the distance from the asteroid belt to the Sun.
The stars in this system, dubbed OGLE-2007-BLG-349, are no less than 11 million kilometers away , 14 times the diameter of the Moon’s orbit around the Earth.
“Observations from Earth suggested two possible scenarios for this system of three objects: a planet with a mass similar to that of Saturn orbiting a pair of nearby binary stars or a planet with the mass of Saturn and a planet of Earth mass orbiting around of a single star ”, explained David Bennett, from NASA’s Goddard Space Flight Center in Greenbelt, Maryland (USA), co-author of the work.
Thanks to the spectacular sharpness of images taken by the Hubble, astronomers were able to observe what and the starlight of the lens system in the foreground was too weak to be a single star, but had the proper brightness of two red dwarfs nearby that orbit each other.
“The model with two stars and one planet is the only one compatible with the Hubble data,” Bennett says.
Now that astronomers have been able to demonstrate the efficacy of gravitational microlensing in detecting planets orbiting star-pair systems, we may find many more such systems thanks to the Hubble telescope.
The study will be published in the Astronomical Journal.
