Have astronomers discovered a second earth? :: wetter.at

An international team of astronomers has discovered a planet with conditions potentially favorable to life. "It's exciting, because it's the first super-land in the region that could house life," said Austrian astrophysicist Lisa Kaltenegger, who participated in the badysis.

Although the proximity is relative here, the star in question GJ 357 is 31 light years from Earth and is in the constellation of the Water Serpent (Hydra). This fund was made possible by NASA's Transiting Exoplanet Survey Satellite (Tess) satellite. With his help, the scientists came in February 2019 on an exoplanet, which partially covered its orbit GJ 357 and thus attenuated its light.

This planet, called GJ 357b, turned out to be about 22% larger than the Earth and surrounds its star eleven times closer than the planet Mercury, the closest to our planet. The temperature at 357 GJ is estimated at 250 degrees Celsius. "We refer to GJ 357B as a so-called hot land," said Stefan Dreizler of the Institute of Astrophysics at the University of Göttingen. "Although the planet can not adapt to life, it is an important step in the exploration of Earth-like planets."

Existence confirmed

The research team led by the Canary Islands Institute of Astrophysics in Tenerife confirmed the existence of GJ 357b. This was done using ground data, recorded since 1998 at the European Southern Observatory and at the Campanas Observatory in Chile, as well as at the Observatory of Keck in Hawaii and at the Calar Alto observatory in Spain. The results have now been published in the journal Astronomy & Astrophysics.

Surprisingly, the scientists later discovered two other exoplanets, named GJ 357c and GJ 357j. While the GJ 357c is likely to be very hot and to have at least 3.4 times the Earth's mbad, the ultimate twin planet of the system, the GJ 357d, could offer conditions such as the Earth, according to one Tess team release on Wednesday.

"One of the best planets"

It is expected that GJ 357 days gravitates around the dwarf star every 55.7 days at a distance of about 20% of the distance from Earth to the Sun. Scientists badume that its mbad is at least 6.1 times that of the Earth. "With a dense atmosphere, the planet GJ 357d could contain liquid water on the surface of it," Kaltenegger said. It is therefore "one of the best planets" to look for signs of life with future telescopes.

The Austrian, who works at Cornell University in Ithaca, New York State, and is part of the Tess mission science team, simulated the possible conditions on the planet in cooperation with doctoral student Jack Madden and clbadmate Zifan Lin. This could have both a rocky composition, but also an aquatic world, as reported in the journal "The Astrophysical Journal Letters". If GJ 357 d was a rocky world, its size would be between one and two times the size of the earth. From its central star, the GJ 357d draws about the same amount of energy as Mars from the sun.

"We have built the first models of what this new world could be, knowing that liquid water can exist on the surface of this planet, which motivates us to look for ways to discover signs of life," said Madden.