A first-year PhD student from the Astronomy department at the U of A, along with a team of astronomers has discovered a planet with three suns. According to uanews, the planet known as HD 131399Ab, is different from any planet discovered to date, in that it is the widest known orbit within a multi-star system.
The researchers estimate the planet to be about 16 million years old, which is one of the youngest exoplanets (planets discovered outside our solar system) discovered yet. HD 131399Ab is a gas giant that is about four times more massive than Jupiter. It is located about 340 light years away from Earth in the constellation Centaurus.
Kevin Wagner, a first-year PhD student responsible for the discovery had this to say about the planet.
"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. 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."
This artist's impression below shows the orbit of the planet in the triple-star system. Two of the stars are very close together, while the third, much brighter star, has the planet HD 131399Ab orbiting around it.