Is named “GJ 367 b”And, although it is somewhat greater than MarsThis small, rocky and very dense exoplanet is one of the heaviest of the nearly 5,000 discovered so far. Its origin is a mystery and studying it will help to find out more about the evolution and formation of the terrestrial planets.
The planet has been discovered by an international group of 78 scientists led by the Planetary Research Institute of the DLR (German Aerospace Center) and the details of the find are published today in the journal Science.
GJ 367 b it has a very large iron core and a small part of silicates like Earth, a composition similar to that of Mercury, which is the planet closest to the Sun in our solar system, “he explains to Efe. Enric Pallé, researcher at the Institute of Astrophysics of the Spanish archipelago of the Canary Islands (IAC) and co-author of the study.
Furthermore, this curious exoplanet, which is only 31 light years from Earth, revolves around a star in approximately eight hours, meaning that “its year lasts less than a day on Earth,” adds the researcher.
Like many exoplanets, GJ 367 b was detected by the satellite TESS of the American space agency NASA that looks for planets in transit, which occurs when a planet passes in front of its star and absorbs part of the light from the star, a phenomenon that is generally studied from space to prevent the atmosphere terrestrial distorts the result of the observation.
Once detected by TESS, astronomers turned to instruments such as the HARPS, from the telescope of the European Southern Observatory (ESO), to determine aspects such as the radial speed of the star or to calculate with great precision the mass and radius of the planet.
The study concludes that, due to its characteristics, GJ 367 b is an exoplanet of “ultrashort period”(USP), which revolves around its star in less than 24 hours, with a radius equivalent to 72% of the Earth’s radius, and a mass close to 55 percent of the mass of the Earth.
These data allowed the researchers to draw conclusions about the internal structure of the exoplanet and concluded that it is a rocky planet with a low mass, but with a density higher than that of Earth.
“The high density indicates that the planet is dominated by a iron core“, Explain Szilárd Csizmadia, researcher at the DLR Planetary Research Institute and first author of the study.
The research also details that the exoplanet orbits a red star called GJ 367 – half the size of the Sun – but so close to it that “it receives 500 times more radiation than the Earth from the Sun, which means that its temperature on the surface it must exceed 1,500 degrees Celsius ”, explains the Spaniard Pallé.
This temperature is sufficient to melt rocks and metals on the surface, so GJ 367 b cannot be considered a “second Earth”, the study points out.
For the Spanish researcher, this planet is “very interesting” because “it is one of the smallest that has been discovered, but also because it is very dense, and that forces us to consider how it got there, since it is almost certain that it was not formed there ”.
One possibility is that “that solar system has hosted other planets – that are still there and we have not detected them yet – and that they have interacted with it or pushed it into this orbit so close to its star,” says Pallé.
“GJ 367 b is not only one of the smallest planets we know of and the ones that rotate the fastest around its star, but it also has a very interesting history that we now have to unravel,” he concludes.
With information from EFE