The common binary star system is made of a planet orbiting around one host star. But there are also binary systems where the planet is orbiting both stars. This kind of planets is officially named circumbinary exoplanets, known as “Tatooine” planets. Their orbital field is called a circumbinary filed.
If you are a Star Wars fan you might be more familiar with them, as you might remember that Luke Skywalker and his father, Anakin Skywalker, lived on this kind of planet. Tatooine was a circumbinary planet. Circumbinary planets and their discs have been the subject for a new study led by astronomer Ian Czekala of the University of California at Berkeley.
With the help of the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers found that the wider the binaries, the more tilted is the disc that encircles it. Previously, scientists already concluded that that the three celestial bodies originate from a single protoplanetary disk.
New research on “Tatooine” exoplanets
Now, from the 19 binary star systems they surveilled, researchers observed that the shorter the orbital period of the host is, the mannered the circumbinary disk by lining up with its orbit. Under 40 days, the disk behaves. Over 40, there comes the tilt! To help get to this conclusion, the researchers used data gathered by the Kepler space telescope on a dozen circumbinary planets.
The new dependence between the time the host star needs to fulfill its orbit and the misalignment of the disk opens a new path. Ian Czekala stated that they now want “to understand how warped or tilted disks affect the planet formation environment and how this might influence the population of planets that form within these disks.”
Due to this odd behavior, scientists now believe that Kepler might have missed some binaries in which misaligned planets orbit around wide binary stars. Kepler is using the transit method to find planets. So, there you go, a new mission for astronomers and spacecraft using direct imaging and microlensing finding techniques!