Noelle Toumey Reetz
Office of the Vice President for Research and Economic Development
ATLANTA—Pioneering new research from an international team of experts, including researchers from Georgia State University, has revealed the first direct evidence that groups of stars can tear apart their planet-forming disk, leaving it warped and with tilted rings.
The researchers have identified a stellar system where planet formation might take place within a warped circumstellar disk around multiple stars. A view from a potential planet around this system will give the observer a stunning view of a tilted, multiple stellar constellation — similar to Star Wars’ Tatooine.
The results were made possible with observations from the European Southern Observatory’s Very Large Telescope (VLT) Interferometer, Georgia State’s Center for High-Angular Resolution Astronomy (CHARA) Array and the Atacama Large Millimeter/Submillimeter Array (ALMA).
The research is the first output of a large program on young stellar systems that uses a pioneering infrared imager, called MIRC-X, which was built by the Universities of Michigan and Exeter as part of a European Research Council-funded research project. MIRC-X combines the light from all six telescopes of the CHARA Array, the world’s largest optical interferometer, located at Mount Wilson Observatory in California and operated by Georgia State.
The Earth’s solar system is remarkably flat, with the planets orbiting in the same plane. This is not always the case, especially for planet-forming disks around multiple stars, like the object of the new study: GW Orionis. This system, 1,200 light-years away in the constellation of Orion, has three stars and a deformed, broken-apart disk surrounding them.
“We’re really excited that our new MIRC-X imager has provided the sharpest view yet of this intriguing system,” said Stefan Kraus, professor of astrophysics at the University of Exeter, who led the research published today in Science. “Normally, planets form around a flat disk of swirling dust and gas — yet our images reveal an extreme case where the disk is not flat at all.”
The team observed GW Orionis for more than 11 years and mapped the orbit of the stars with unprecedented precision. The researchers were able to image the inner ring and map the structure of the disk with the SPHERE instrument on ESO’s VLT and ALMA. Using computer simulations, they were able to clearly link the observed misalignments to the theoretical disk-tearing effect, which suggests the conflicting gravitational pull of stars in different planes can warp and break their surrounding disk.
The research also reveals the inner ring contains 30 Earth masses of dust around the stars, which could be enough to form planets.
“This result provides an exciting possibility that we could find an undiscovered population of planets that orbit star systems in wide, inclined orbits,” said Gail Schaefer, one of the paper’s co-authors and associate director of the CHARA Array.
Theo ten Brummelaar, director of the CHARA Array, also contributed to the research.