The most recent exoplanet that was discovered is the super-Earth LHS 1140b in the constellation Cetus 40 light years away. The planet orbits ten times closer to its star compared to Earth,but it is positioned in the middle of the habitable zone. It is seen almost edge-on from Earth and it’s orbit duration is just 25 days.
“This is the most exciting exoplanet I’ve seen in the past decade,” said lead author Jason Dittmann of the Harvard-Smithsonian Center for Astrophysics. “We could hardly hope for a better target to perform one of the biggest quests in science — searching for evidence of life beyond Earth.”
“The present conditions of the red dwarf are particularly favourable — LHS 1140 spins more slowly and emits less high-energy radiation than other similar low-mass stars,” explains team member Nicola Astudillo-Defru from Geneva Observatory.
Red dwarfs in their early stages of life emit large amount of radiation that can be harmful to the planets atmospheres. On this particular exoplanet, a magma ocean might have existed which could’ve caused steam in the atmosphere and replenished the planet’s water reserves.
The exoplanet was discovered from the MEarth facility and then the later observations from ESO’s HARPS instrument, the High Accuracy Radial velocity Planet Searcher. HARPS also pinned down the planet’s orbit and measured it’s size and density.
The estimated age of the planet is 5 billion years. It is 1,4 times larger than Earth, but with its 7 Earth masses, it is a dense rocky planet with a large iron core.
LHS 1140b is one of the best candidates for its atmosphere to be measured, assuming it has one. Xavier Delfosse and Xavier Bonfils “The LHS 1140 system might prove to be an even more important target for the future characterisation of planets in the habitable zone than Proxima b or TRAPPIST-1. This has been a remarkable year for exoplanet discoveries!” – said team members Xavier Delfosse and Xavier Bonfils.
New observations coming soon from NASA/ESA Hubble Space Telescope will measure in how much radiation LHS 1140b basks, helping to find if it is really habitable.
Source : Sciencedaily.com