Rare haul: 50 exoplanets and 16 super-Earths found

European astronomers have found 50 distant planets orbiting stars and 16 rocky “super-Earths”, planets that theoretically…

An artist’s impression of one of 16 new super-Earths recently found. This one orbits the Sun-like star HD 85512 in the southern constellation of Vela (The Sail). ESO/M. Kornmesser

European astronomers have found 50 distant planets orbiting stars and 16 rocky “super-Earths”, planets that theoretically could support life.

Expolanets, which orbit stars outside our solar system, were once considered a fringe science but are now seen as our best bet of finding conditions that could support extra-terrestrial life.

Super-Earths, planets more massive than the Earth but less than 10 times its mass, are not truly Earth-like but are thought to be slightly more similar to our terrestrial planets than most.

Astronomers from the European Southern Observatory (ESO) announced at a conference on Extreme Solar Systems in Wyoming that they had located the exoplanets planets using HARPS, the High Accuracy Radial velocity Planet Searcher located at the ESO La Silla Observatory in Chile.

“The harvest of discoveries from HARPS has exceeded all expectations and includes an exceptionally rich population of super-Earths and Neptune-type planets hosted by stars very similar to our Sun. And even better — the new results show that the pace of discovery is accelerating,” the HARPS team leader, Michel Mayor from the University of Geneva in Switzerland, said in a statement.

Among the super-Earths discovered is HD 85512 b, estimated to be just 3.6 times the mass of Earth.

“These planets will be among the best targets for future space telescopes to look for signs of life in the planet’s atmosphere by looking for chemical signatures such as evidence of oxygen,” said Francesco Pepe from the Geneva Observatory in Switzerland.

Jonti Horner, an exoplanet expert and Post Doctoral Research Fellow at University of New South Wales, said HD 85512 b was “the sexiest part of the discovery announcement” because it may lie on the edge of the Goldilocks zone, just far enough from its host star to support water in liquid form.

“In other words, if conditions were otherwise right, [it] could be the kind of place where you could find "life as we know it” - if you stretch your imagination far enough,“ he said.

The sheer number of expolanets found in this haul was also remarkable, Dr Horner said.

“Taking this announcement and that of 23 new WASP planets together (which was also announced at that conference), we’re looking at the number of known exoplanets having increased by around 10% in just two days,” he said.