New Delhi | Jagran Trending Desk: An exoplanet, which is scorching hot and as dense as pure iron, has been discovered by the scientists outside the solar system. The scientists on Thursday said that the planet lies about 31 light-years away in the constellation of Vela and is about three-quarters of the size of Earth and half as massive. The planet, which known as GJ 367 b, takes less than eight hours to orbit a red dwarf star half the size of the Sun.

"Discovery Alert! An international team of scientists used @NASA's TESS spacecraft to find a tiny planet hugging a red star. A ''year'' there, one orbit, takes less than 8 hours! It's 31 light-years from Earth, and hot enough to melt metal," the NASA Exoplanets tweeted.

Scientists are eager to find exoplanets, as these alien worlds are known, that might harbor life. GJ 367b, certainly could not, possessing ferocious surface temperatures and perhaps a molten lava surface on the side facing its star, they said. But other small exoplanets found and studied using the same methods might emerge as good candidates for nurturing extraterrestrial life.

Ever since the first exoplanet was discovered, scientists have taken a deeper interest in characterising them more precisely in order to gain a thorough understanding of their variety, from large gas giants akin to Jupiter to smaller rocky Earth-like planets where life might thrive.

“Gas giants such as Jupiter, as we know it, are not habitable because they have more extreme temperatures, weather, pressures, and a lack of essential building blocks to support life,” said astronomer Kristine Lam of the Institute of Planetary Research at the German Aerospace Center (DLR), lead author of the study published in the journal Science.

“Unlike gas giants, small terrestrial worlds like Earth are more temperate and consist of important ingredients, such as liquid water and oxygen, to harbor life forms. Although not all terrestrial exoplanets are habitable, searching for smaller worlds and identifying the type of planets they are can help us understand how planets were formed, what makes a planet habitable and if our solar system is unique,” Lam added.

GJ 367b has a diameter of about 9,000 km and has 55 per cent mass, whereas Earth's diameter is 12,700 km and Mars has 6,800 km diameter.

During the research, the researchers calculated that 86 per cent of GJ 367b is composed of iron, with an interior structure resembling Mercury, which is the closest planet to Sun. Scientists are wondering that whether the GJ 367b lost an outer mantle that once encased its core.

“Perhaps like Mercury, GJ 367b could have experienced an episode of giant impact which stripped away the mantle, leaving behind a large iron core. Or maybe the exoplanet is a remnant of a Neptune or super-Earth sized gaseous planet, where the atmosphere of the planet has completely blown away as the planet is blasted by a large amount of radiation from the star,” Lam said.

It orbits very close to a red dwarf star that is smaller, cooler, and less luminous than Sun – more than 99 per cent closer than Earth’s distance to the sun, according to astronomer and study co-author Szilard Csizmadia, also of the DLR’s Institute of Planetary Research.

GJ 367b orbits its star once every 7.7 hours, placing it in a category of “ultra-short period” exoplanets that travel around their home stars in less than 24 hours.

One side of GJ 367b probably faces its star at all times, with surface temperatures up to about 1,500 degrees Celsius. “This temperature is high enough to evaporate any atmosphere that GJ 367b might have had in the past, as well as melting any silicate rocks and metallic iron on the planet,” Lam said.

(With agency inputs)

Posted By: Mallika Mehzabeen