Astronomers have just identified 27 new potential planets that orbit two stars, reminiscent of Tatooine from the Star Wars universe. Until now, only 18 circumbinary planets were known, while over 6,000 planets orbit single stars like our sun.
In a fitting announcement for Star Wars Day on May 4, scientists revealed these candidate planets, which are located between 650 and 18,000 light-years away from Earth. “Astronomy can be abstract,” said Assoc Prof Ben Montet from the University of New South Wales (UNSW). The iconic Tatooine sunset from the original film helps many visualize what a planet with two suns might be like.
Interestingly, more than half the stars in the universe exist in binary or multiple star systems. Scientists usually find circumbinary planets by observing their transits. When a planet passes in front of a star, it casts a shadow, causing a brief dip in brightness. However, this only happens when everything aligns perfectly with our viewpoint from Earth. As Montet noted, “We’re missing lots of systems, potentially.”
Detecting these planets is tricky, akin to spotting a candle next to a streetlight. The researchers used a different method called “apsidal precession.” By monitoring changes in the timing of two stars eclipsing each other, they noticed a wobble that implied the presence of a third body.
Margo Thornton, the study’s lead author and a PhD candidate at UNSW, explained, “If we observe the timing of these eclipses, it can reveal other objects in the system.” After sifting through data from 1,590 star systems, they identified 36 that hinted at additional bodies, with 27 of them potentially being planets.
Using information from NASA’s Transiting Exoplanet Survey Satellite, they found these objects could vary dramatically in size. Some might be as small as Neptune, while others could be ten times the mass of Jupiter.
Dr. Sara Webb, an astrophysicist at Swinburne University, praised the team’s innovative techniques. She suggested that similar methods could help uncover even more planets in the future. However, the extreme conditions of circumbinary planets would be a stark contrast to Earth. Webb noted there may be locations in their orbits where conditions are just right—like Tatooine’s famed landscape.
It’s fascinating to think that when Star Wars first premiered, the existence of exoplanets was purely theoretical. Today, as our understanding of the universe expands, some artistic predictions about star systems align with scientific discovery.
This research was published in the Monthly Notices of the Royal Astronomical Society. For more details on recent discoveries, check out this article on NASA’s Curiosity rover finding organic molecules on Mars.
