Scientists have discovered several strange attributes of this mysterious exoplanet far away from our solar system.
It’s about 320 light years away from us and it’s arguably one of the most bizarre planets mankind has ever discovered.
This large exoplanet has not one, not two, but three suns — meaning its got Tatooine in Star Wars beat. Astronomers found HD 131399Ab and detailed their findings in a paper published in the journal Science.
They used direct imaging to discover it, and they discovered something else strange about the planet: it shouldn’t exist at all, according to a University of Arizona statement.
The orbit of the exoplanet suggests that it should be ejected from this star system. That’s because typically planets in multiple-star systems orbit much closer to one of the stars, and the other stars are much farther off in the distance so they don’t tug at the planet much as well. But this exoplanet is a third of the way in between the stars.
So while the planet orbits the first star, its orbit brings it close to the two other stars, which themselves are close together. That means they pull on the orbit of the exoplanet. However, the orbit appears stable anyway.
“HD 131399Ab is one of the few exoplanets that have been directly imaged, and it’s the first one in such an interesting dynamical configuration,” said Daniel Apai, an assistant professor of Astronomy and Planetary Sciences who leads a research group dedicated to finding and observing exoplanets at the UA.
“For about half of the planet’s orbit, which lasts 550 Earth-years, three stars are visible in the sky, the fainter two always much closer together, and changing in apparent separation from the brightest star throughout the year,” said Kevin Wagner, a first-year PhD student in Apai’s research group and the paper’s first author, who discovered HD 131399Ab. “For much of the planet’s year the stars appear close together, giving it a familiar night-side and day-side with a unique triple-sunset and sunrise each day. As the planet orbits and the stars grow further apart each day, they reach a point where the setting of one coincides with the rising of the other – at which point the planet is in near-constant daytime for about one-quarter of its orbit, or roughly 140 Earth-years.”