Scientists spot a triple star system shredding its planet-forming disc
Groups of stars can tear their planet-forming disc to shreds, leaving behind warped, misaligned rings. Solar systems like ours generally form with their planets all orbiting in the same flat plane – but this isn’t always the case. After 11 years studying GW Orionis, a young triple star system lying 1,300 light years away with a circumstellar disc, a team of researchers found the first direct evidence that groups of stars can actually tear apart their discs. This work reveals a disc that isn’t flat at all, and is instead misaligned and broken.
“There have been a number of theoretical studies on disc-tearing effects, but this is the first direct evidence of the effect occurring in a planet-forming disc,” said Alison Young of the University of Exeter, UK “This demonstrates that it is possible for such discs to be warped and broken, and raises the possibility that planets could form on highly inclined orbits around multiple star systems.”
The warped ring, which is located in the inner part of GW Orionis’ disc, contains 30 Earth masses of dust. This means that the disc contains enough material to form planets. “It’s the best mechanism for forming planets on such extreme orbits to be found so far,” said Stefan Kraus, a professor of astrophysics at the University of Exeter, referring to the warping observed in GW Orionis. “But from the planet-detection side, we don’t have a way of detecting these planets yet.
While the researchers have yet to detect planets within this system, the study confirms what scientists have suspected for years: that multi-star systems can break their own discs, leaving inclined, misaligned rings around the stars.