from the Ross-128?-When-did-Harry-Mudd-join-"Friends"? dept.
Astronomers using the High Accuracy Radial velocity Planet Searcher (HARPS) at the La Silla Observatory in Chile have discovered an Earth-sized exoplanet orbiting a red dwarf in its "habitable zone". The star, Ross 128, is about 10.89 light years away and is less active than Proxima Centauri, possibly boosting the chances of its exoplanet being habitable. Ross 128b has a minimum mass of about 1.35 Earth masses, and is considered by its discoverers to be "the best temperate [exo]planet known to date". The next step will be to determine the atmospheric composition of Ross 128b:
There's still uncertainty about whether Ross 128 b is within its star's habitable zone, but scientists say that with temperatures of between -60 and +20°C, it can be considered temperate.
Next, astronomers want to study the atmospheric composition and chemistry of suitable, nearby worlds like Ross 128 b. The detection of gases such as oxygen could potentially point to biological processes on planets orbiting other stars.
Several gases have already been detected in the atmospheres of exoplanets, but this line of enquiry is expected to be boosted immeasurably when observatories such as the European Southern Observatory's Extremely Large Telescope (E-ELT) and Nasa's James Webb Space Telescope (JWST) come online in the next few years.
Although currently 11 light-years from Earth, the new planet's parent star Ross 128 is moving towards us and is expected to overtake Proxima Centauri as our nearest stellar neighbour in just 79,000 years - a heartbeat on cosmic timescales.
A temperate exo-Earth around a quiet M dwarf at 3.4 parsecs (open, DOI: 10.1051/0004-6361/201731973) (DX)