European astronomers find "super-Earths"



Astronomers Michel Mayor (R) and Stephane Udry (L) of Switzerland's Geneva Observatory attend an astronomy conference in Nantes, western France, Monday June 16, 2008. European astronomers had located dozens of giant planets in three distant solar systems.

This artist's impression by the ESO website shows a trio of super-Earths discovered by an European team. European scientists on Monday said they had located ive "super-Earths," each of them between four and 30 times bigger than our planet, in a trio of distant solar systems.

(Xinhua 06-17-2008 16:40)BEIJING, June 17 (Xinhuanet) -- European scientists on Monday said they had discovered a batch of five "super-Earths," each of them between four and 30 times bigger than our planet, in a trio of distant solar systems.

Their findings, presented at a conference in France, suggests that at least one third of stars similar to our own Sun host these difficult-to-detect celestial bodies, multiplying previous estimates by five.

It also brings astronomers closer to finding planets outside our solar system, called exoplanets, that could potentially duplicate the conditions that gave rise to life on Earth.

"In a year or two, it is likely that we will find habitable planets circling small stars" such as the sun, said Setphane Udry, a researcher at Switzerland's Geneva Observatory and a member of the team that made the discovery.

The trio of planets orbit a star slightly less massive than our sun, 42 light-years away towards the southern Doradus and Pictor constellations. A light-year is the distance light can travel in one year.

The planets are bigger than Earth -- one is 4.2 times the mass, one is 6.7 times and the third is 9.4 times.

They orbit their star at extremely rapid speeds -- one whizzing around in just four days, compared with Earth's 365 days, one taking 10 days and the slowest taking 20 days.

Udry and colleagues used the High Accuracy Radial velocity Planet Searcher or HARPS, a telescope at La Silla observatory in Chile, to find the planets.

HARPS, sometimes called the "planet hunter", has uncovered 45 super-Earths since it began operation in 2004.