Number of Known Exoplanets Has Reached 700

According to the Extrasolar Planets Encyclopedia, a database compiled by astrobiologist Jean Schneider of the Paris-Meudon Observatory, less than 20 years after discovering the first world beyond our solar system at present is known 702 exoplanets. Schneider’s list is one of two main alien-world trackers out there. The other is called “PlanetQuest: New Worlds Atlas,” run by NASA‘s Jet Propulsion Laboratory. PlanetQuest’s current count stands at 687; the difference between the two databases highlights the uncertainties involved in exoplanet detection and confirmation. Astronomers first discovered an alien world in 1992, when researchers detected two planets orbiting a rotating neutron star, or pulsar, about 1,000 light-years from Earth.

Confirmation of a planet circling a “normal” main-sequence star other than our sun did not come until 1995. But have to say that the count topped 500 in November 2010, and it passed 600 just two months ago when scientists with the European Southern Observatory announced 50 newfound planets, including one “super-Earth” that might be a good candidate for hosting life. And the pace of discovery is only going to keep accelerating, as scientists continue to hone their planet-hunting techniques and the data continue to pour in. According to scientists they search extrasolar planets to better understand the nature and variety of planets.
source:www.space.com