European Astronomers Find 32 New Exoplanets

32 new planets orbiting stars outside our solar system have been discovered, a team of European astronomers announced today. The find is believed to mean that 40% or more of stars similar to our sun have such planets. The discovery was announced at the ESO/CAUP exoplanet conference in Porto, Portugal by the team who built the High Accuracy Radial Velocity Planet Searcher, better known as HARPS.

HARPS is a spectrograph linked to the European Southern Observatory's 3.6-meter (11.8-foot) telescope in La Silla, Chile. Over the past five years, HARPS has found more than 75 of the 400 or so known exoplanets.

"HARPS is a unique, extremely high precision instrument that is ideal for discovering alien worlds," says Stephane Udry, Geneva Observatory in Switzerland. "We have now completed our initial five-year programme, which has succeeded well beyond our expectations.

The planets are a range of sizes from about five times the size of Earth (known as super-Earths and Neptune-like planets) to about five times the size of Jupiter.

ESO is the European Southern Observatory, Europes intergovernmental astronomy organisation, supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom.

HARPS was built in 2003 and is able to measure the back-and-forward motions of stars by detecting small changes in a stars radial velocity, as small as 3.5 km/hour, a steady walking pace. Such a precision is vital for the discovery of exoplanets and the radial velocity method, which detects small changes in the radial velocity of a star as it wobbles slightly under the gentle gravitational pull from an (unseen) exoplanet, has been most prolific method in the search for exoplanets.