Astronomers discover two rare binary star systems with remarkable disk around them

Astronomers have discovered two rare star systems comprising two central stars orbiting each other. The new binary star systems are rare because their disks lie at an angle to the orbits of their central stars.

The two objects, designated Bernhard-1 and Bernhard-2, are so distant that their two central stars can't be seen individually (such pairs of stars are known as binary stars). The discovery of these rare objects is described in a paper in the Astrophysical Journal Letters.

"If there were a planet in one of these systems, it would be like the planet Tatooine from Star Wars. You would see two suns in the sky orbiting each other. In addition, there's a disk around the stars. Picture Saturn's rings but much, much larger - with the stars in the middle," said Michael Poon, a PhD student in the Faculty of Arts & Science's David A. Dunlap Department of Astronomy & Astrophysics and one of two University of Toronto researchers involved in the discovery of the binary star systems.

Such disks are called protoplanetary disks because they eventually form into families of planets like our solar system, according to researchers.

The researchers identified the new objects by analyzing their light curves. The light curves of the new systems match that of the first such system ever discovered - Kearns Herbst 15D (KH 15D).

According to the researchers, the disk of binary stars typically lies in the same plane as the orbits of the stars - just as the orbits of most of the planets and moons in our solar system lie on the same plane. However, Bernhard-1 and Bernhard-2 are rare in that their circumbinary disks are at an angle to the planes of the orbiting stars.

With this discovery, the researchers are optimistic that more discoveries will follow. More information can be found here.