Scientists discover planet orbiting three stars could be hiding an even bigger secret

The planet has broken rings that could have been ripped apart by another world forming between them and the planet

(ESO/L. Calçada, Exeter/Kraus et)

Astronomers have discovered a planet 1,300 light years from Earth that is bizarrely orbiting three stars, rather than just one.

The strange celestial object, GW Ori, also has a disc split in two at a strange 38-degree angle – as if the rings of Saturn were broken in the middle and tilted askew.

Inside those inner rings are 30 Earth-masses of dust which could be enough to form planets.

Such a discovery is an “extreme case”, Stefan Kraus, a professor of astrophysics at the University of Exeter said, as discs around a planet are usually flat, rather than warped and misaligned.

“Any planets formed within the misaligned ring will orbit the star on highly oblique orbits and we predict that many planets on oblique, wide-separation orbits will be discovered in future planet imaging campaigns”, added team member Alexander Kreplin.

The team had been studying this strange planet, located in the constellation of Orion, for 11 years, using various measurement tools to examine the gravity of the stars it orbits and map their movements.

Computer simulations suggested that the conflicting gravitational pulls of the three stars broke the disc apart, but research from another team who studied the system came to a different conclusion: “We think that the presence of a planet between these rings is needed to explain why the disc tore apart,” says Jiaqing Bi of the University of Victoria in Canada.

These scientists believe that the gravitational power of the three stars is not enough to rip the disc apart. Observations from the ALMA telescope and Very Large Telescope in Chile, made over the next few months, could reveal the truth to scientists.

“We’ll be able to look for direct evidence of a planet in the disk,” Dr Alison Young from the University of Leicester in England told the New York Times.

There are several circumbinary planets which orbit two stars, but only a smattering have been found that orbit three – although it has been estimated that one tenth of all stars are clustered in this way, and it’s possible that planets could orbit even more stars.