January 31, 2014
Study Gives Insight Into How Skywalker’s Tatooine May Have Formed
Lee Rannals for redOrbit.com - Your Universe Onlinecircumbinary planets. These planets, like Kepler-34(AB)b, have an orbit that encompasses two stars, and the latest study gives insight into what Skywalker’s home might have actually looked like in the real world.
These planets face some of the most extreme conditions you could dream up, with powerful gravitational perturbations from the stars leading to destructive collisions that grind down the material. However, despite the harsh conditions these planets do in-fact exist.
Dr. Zoe Leinhardt and colleagues, from Bristol's School of Physics, performed computer simulations of the early stages of planet formation around the binary stars using a model that calculates the effect of gravity and physical collisions on and between one million planetary building blocks. They discovered that the majority of these planets had to have formed much farther out from the central binary stars and then migrated to their current location.
The researchers said they improved upon previous studies that have looked at these circumbinary planets by including planetesimal disk self-gravity and an extensive collision model to accurately handle inter-planetesimal interactions.
"Our simulations show that the circumbinary disk is a hostile environment even for large, gravitationally strong objects,” Leinhardt said in a statement. “Taking into account data on collisions as well as the physical growth rate of planets, we found that Kepler 34(AB)b would have struggled to grow where we find it now."
The team said it is possible that Kepler-34(AB)b migrated from a region beyond 1.5 astronomical units. According to the study, all of the currently known circumbinary planets have migrated significantly from their formation locations. This means that even Tatooine had to have formed far from the binary Tatoo star system.
"Circumbinary planets have captured the imagination of many science-fiction writers and film-makers - our research shows just how remarkable such planets are. Understanding more about where they form will assist future exoplanet discovery missions in the hunt for earth-like planets in binary star systems,” Stefan Lines, lead author of the study published in the Astrophysical Journal Letters, said in a statement.