Tatooine’s Twin Stars
One of the most iconic planets in Star Wars, Tatooine is the home planet for Luke and Anakin Skywalker. Scientists have long thought it to be an impossibility for a planet to orbits a twin star, but recent findings suggest that the possibility of a habitable planet circling a pair of stars might not be so far-fetched after all.
Theoretical investigations into a planet with twin stars, or scientifically known as binary stars, are just as likely to form around a single star, like here on Earth or a planet like Tatooine. That is because more than half of the stars in the galaxy have a stellar companion.
In 2005, of the 130 known exoplanets, roughly 20 of them orbits around binary stars and the number is likely to grow higher. Previously, planet hunters tend to avoid searching for planets in binary systems as the interaction can hide planet signatures. However, the latest figure puts the number of exoplanets orbiting binary stars to be 111.
First confirmed planet
The first planet confirmed to have Tatooine-like quality is the Kepler-16B, which is situated over 200 light years away with a mass similar to Saturn. It orbits a close binary star, which rises and set together and eclipses at a frequency of 20 days or so. Despite the arrangement, there will never be constant daylight on Kepler-16B as the two stars are so close together. While the temperature on the planet ranges from -70 C to -100 C.
Interstellar concerns
Primary problems with exoplanets orbiting twin suns are due to the gravity of one star might prevent planets from the developing around each other. Also, different masses of the twin stars orbiting around each other would cause shifts in gravity fields, resulting in instabilities in the orbits of any planets in their system
Problems with exoplanets circling binary star do not stop at its orbit. Climate concern would also prevent from any life form to form on within a binary star system. A planet orbiting a larger star would have to endure extreme heat while orbiting the smaller star; the planet would plunge the planet in extremely low temperatures.
A Possible Tatooine
Astronomers hypothesise that there are two possibilities, for a life supporting binary star
system to exist. If the two stars are set billions of miles apart, life could be supported on such a planet as it will exert minimal influence from one another. Astronomers have observed that Proxima Centauri to fit this prerequisite, as it is a trillion miles away from its sister stars. If a planet like this does exist, it is assumed that these sister stars would appear as bright stars in the sky.
On the other hand, a close binary star circling close to each other at a distance of a few million miles could support life if the orbiting planet is far enough to be affected by the gravity field of the twin sun as though it was one. The distance between the two stars also has to be a fraction of the distance to the planet for a stable orbit. In reaching these conditions, the planet’s twin sun would be able to chart a similar trajectory to the twin suns of Tatooine, as first seen in Star Wars IV: A New Hope.
