New 'Star Wars' Planet Is Nothing Like Tatooine

Scientists have discovered planets orbiting a binary star system just like the fictional planet Tatooine, in a solar system far, far away.

The researchers found the planet by accident as they attempted to study a different planet named BEBOP-1b, a planet they had already found orbiting a binary star system—two stars orbiting each other closely—named BEBOP-1, situated around 1,320 light years away. In the process, they discovered a second planet in the system, which they named BEBOP-1c, according to a paper published in the journal Nature Astronomy.

Unlike Tatooine, however, this planet is unlikely to be able to host lifeforms—even Jedis.

In the Star Wars universe, Tatooine is a planet orbiting a binary star system, with two suns being seen in the sky during the planet's iconic sunset.

Unfortunately for Star Wars enthusiasts, BEBOP-1c is unlikely to have aliens of any form living on it, as it is thought to be a gas giant like Jupiter, around 65 times more massive than the Earth.

Rosemary Mardling, a senior lecturer at Monash University's School of Physics and Astronomy, and co-author of the study, told Newsweek: "The new planet is about as far from the binary as our Venus is from the sun."

"So its surface temperature may well be 'not too hot, not too cold' for life. But the planet is a 'gas giant' like our Saturn and so has no solid surface—it is, therefore, unlikely to harbor life. But if the planet has moons, they could well harbor life."

Orbiting a binary star system may come with some strange conditions on the planets, with multiple sunrises and sunsets each day, and weird, unstable orbits.

"The light and other radiation reaching the surface of such a planet (which determine the conditions for life amongst other things) would just be the sum of that from each of the stars," Mardling said.

"In the case of BEBOP-1, one of the stars is like the sun and the other is a very dim (and much cooler) red star which contributes only about 1 percent as much light."

This type of star system may not limit the evolution of life, however, if the conditions are right. Research presented at the American Astronomical Society meeting in January this year revealed that many of these types of planets may indeed be habitable, and settled into a stable orbit in their Goldilocks Zone—the region in a star system where liquid water can exist on an orbiting planet's surface.

"The gravitational effect on a planet from two stars instead of one is minimal at the distance planets can safely exist. Unlike single stars which can have planets orbiting extremely close to their stars (orbiting once per day for example), circumbinary planets need to be at least 3 times the distance between the binary stars themselves. Any closer and they would be ejected from the system by the gravitational effects of the binary," Mardling said.

"For BEBOP-1, the inner planet (with an orbit period of 95 days) is almost as close to the binary as it can safely be. The planet our group discovered has a period of 215 days and so is very little affected by the binary."

"The main difference is what one would see in the sky—it would look much like Tatooine," Mardling said. "Although the red star would be somewhat smaller and the stars further apart."

This discovery marks the second time ever that multiple planets have been spotted orbiting the same multi-star system, known as circumbinary planets.

The first planet orbiting multiple stars was discovered in 2011 and named Kepler-16b, with 14 further circumbinary planets having been discovered thus far. The only other instance of multiple circumbinary planets being found in the same system were the three planets orbiting the Kepler-47 system, discovered in 2012. In 2021, the first "circumtriple planet" orbiting three stars at once was found and named GW Orionis.

"Our team used the 'radial velocity' method to discover the new planet using telescopes at the European Southern Observatory (ESO) in Chile," Mardling said."This method detects the back-and-forth wobble of stars which happens when a planet is orbiting (for the same reason a person doing hammer throw wobbles back and forth). It is the first time this method has been successful at finding a circumbinary planet. Note that this method was used to discover the very first exoplanet in 1995."

So few planetary systems of this form have been found because of how hard it is to spot them.

"We still don't know [how common they are] because they are difficult to detect," Mardling said. "So far we know of around 20 systems (compared to around 4,000 single-star systems), but it is likely that most binaries like BEBOP-1 have planets orbiting them."

One day we may therefore find many more circumbinary planets that are much more capable than BEBOP-1 in hosting life, leaving hope that there may be some alien species out there, living out their Tatooine fantasy.

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