Planets with three suns: the reality that surpasses the imagination of 'Star Wars'

Reality has surpassed the imagination that led Star Wars to invent Tatooine, the desert planet of two suns, home of Luke Skywalker, the Jawas, the sand dwellers, and where Darth Vader was born.. Tatooine, in reality, was a Tunisian desert, and therefore had only one sun. However, in 2020, NASA's TESS space telescope; and last June two telescopes in the Atacama Desert discovered the planets, TOI-1338b and BEBOP-1c, which were part of two circumbinary systems. That is, both TOI-1338b and BEBOP-1c revolved around two suns. That is, if we were on the surface of TOI-1338b or BEBOP-1c, and we raised our heads, we would see the same two suns as Luke on Tatooine.

Now, PhD student Jonathan Dodd, and Professor René Oudmaijer, both from the School of Physics and Astronomy at the University of Leeds; together with Dr. Miguel Vioque of the ALMA Observatory in Chile, and Dr.. Abigail Frost from the European Southern Observatory in Chile has just upped the ante to three soles.

“The best reference point for this is Star Wars,” Dodd acknowledges in research just published by Monthly Notices of the Royal Astronomical Society.

The work is based on massive Be stars, discovered 150 years ago by the Italian astronomer Angelo Secchi in 1866.. They are surrounded by a disk of gas, similar to that of Saturn's rings in our own Solar System, but so far no one knows how they formed.

Surface of the planet Tatooine with two suns in 'Star Wars'.

The astronomical consensus suggests that the disks are the result of the rapid rotation of the star itself, or the interaction of a second nearby star.. But after analyzing data from the European Space Agency's Gaia satellite, scientists have found evidence that these stars not only exist with the help of a second star, but also a third, with three bodies interacting with each other.

To reach this conclusion, astronomers observe the way stars move in the night sky for periods of 10 years and six months.. “If a star moves in a straight line we know there is only one star, but if there is more than one, we will see a slight wobble or, at best, a spiral,” explains Dodd.

The researchers focused on Be and B, which are those found in the last stage of stellar evolution, when a red giant loses its outer layers of hydrogen before nuclear fusion of helium begins in its core.

Then they looked for companion stars that were far away and discovered that, against all predictions, at the largest separations, the rate of companion stars was very similar between B and Be stars, when it should be the other way around, which is why they believe there are missing stars.. “The fact that we don't see them could be because they are now too faint to be detected,” says Professor Oudmaijer, lead researcher.

From this they deduced that, in many cases, a third star comes into play, which came close enough to its star Be to transfer mass to it and form its characteristic disk.. These stars have become too small and faint to be detected, after the 'vampire' star Be had absorbed much of their mass.

Star with a solar disk close to a second star. IT/L. CALÇADA

“Over the last decade, astronomers have discovered that binarity is an incredibly important element in stellar evolution. But now we are getting closer to the idea that it is more complex than that, and that it is necessary to consider triple stars,” says Oudmaijer.. “In fact,” he adds, “triples have become the new binaries.”

The discovery could have enormous impacts on other areas of astronomy, including our understanding of black holes, neutron stars and the sources of gravitational waves, the researchers say.

“There is currently a revolution taking place in physics around gravitational waves. We have only been observing these waves for a few years, and it has been discovered that they are due to the merger of black holes. We know these enigmatic objects exist, but we don't know much about the stars that will become them. Our findings provide a clue,” Oudmaijer concludes.