Binary star sunset

Imagine a sunset on a planet orbiting two stars: a real scenario in binary systems discovered by telescopes like Kepler.

About this subject

In binary star systems, two stars orbit a common center of mass. About half of the stars in the Milky Way are in multiple systems. Exoplanets orbiting binaries are known as circumbinary planets. The first was discovered in 2011 by the Kepler telescope: Kepler-16b, orbiting two orange dwarfs, 200 light-years from Earth. This planet has a mass similar to Saturn and completes an orbit every 229 days. The sunset on such a world would be spectacular: the two stars set at different times, creating multiple shadows and varied colors. The habitable zone of a binary system can be complex, as the combined radiation of both stars influences temperature. In 2020, the TESS telescope discovered TOI-1338 b, another circumbinary planet. These worlds are rare but help understand planetary formation in extreme environments. Science fiction popularized the idea with Tatooine in Star Wars, but the scientific reality is equally fascinating.

Frequently Asked Questions

Could life exist on a planet with two suns?

Yes, theoretically. The habitable zone depends on the distance and type of stars. Circumbinary planets can have stable climates if the orbit is suitable, but combined radiation may be challenging.

How many circumbinary planets have been discovered?

As of 2025, more than a dozen have been confirmed, such as Kepler-16b, Kepler-34b, Kepler-35b, and TOI-1338 b. The number grows with new telescopes.

How do circumbinary planets form?

They form in protoplanetary disks around the binary pair, but the gravity of the two stars can complicate the process. Models suggest it is possible in stable, massive disks.