One of the most iconic images of science fiction are the two suns that we see shine in the distance, in the arid landscapes of Tatooine, in Star wars. But nevertheless, a newly discovered planet apparently adds another star to the sky.
Baptized as LTT 1445Ab in the data collected by NASA's Exoplanet in Transit Study Satellite (TESS), it orbits only one of the three stars, all of them red dwarfs in the second half of their lives, and the system is about 22.5 light years from Earth.
"If you are standing on the surface of that planet, there are three suns in the sky, but two of them are quite far and small in appearance," says co-author of the finding. Jennifer Winters, astronomer of the Harvard-Smithsonian Center.
From the TESS data, it is believed that the planet is rocky, approximately one third larger than the Earth and is at most 8 times more massive. Its surface is very hot: 160 degrees Celsius. And orbit a star every 5 days.
But what is particularly special is something that scientists still cannot characterize but that will soon be able to: its atmosphere. Because the stars in question are red dwarfs that are reasonably close to the planet, and because the system is organized so that the planet passes between the stars and the Earth, scientists can glimpse the gases surrounding the planet using telescopes on the ground.
Astronomers cannot yet take advantage of this particular condition to characterize the atmosphere, but it is exactly the kind of perspective for which the TESS was designed. The instrument, which is in the middle of its initial two-year study of most of the sky, looks for planets with short years located near bright and nearby stars, the perfect objectives for the instruments to observe the atmospheres.