A University of Arizona graduate student identified the first planet ever found in a wide orbit inside a triple-star system.
Kevin Wagner is a first-year doctoral student in the U of A astronomy department. He found the planet when surveying about 100 stars, using the Very Large Telescope in Chile.
The orbit of such a planet influenced by a trio of stars would be expected to be unstable, likely resulting in the planet being ejected from the system. This planet, whose mass is four times that of Jupiter, has survived.
“This planet that we have just discovered orbits out in the middle in between the stars, so the gravity of these other stars can pull it into irregular orbits and cause exotic behavior that we haven’t seen in any other exoplanet before,” Wagner said.
The planet is 320 light years from Earth. Wagner said his research team has a picture of the object, but it appears as a distinct point of light without any surface details.
Planets in multi-star systems are of interest to scientists because they can offer clues about planetary formation.
The findings were published Thursday in the journal Science.