As reported by BBC News, the total number of extra-solar planets known through the efforts of worldwide astronomers has just passed 1000. Keele astronomers pushed it over that number by announcing 12 new planets from the WASP (Wide Angle Search for Planets) survey.
Keele University operates the WASP-South survey cameras, scanning the night skies and watching for small dips in the light of a star when a planet passes in front of ("transits") the star. The new announcements include WASP-100 and WASP-101, the hundredth and hundredth-and-first planets found by the WASP team.
The WASP planets are "hot Jupiter planets", large Jupiter-size gaseous planets in tight orbits around their stars, transiting every few days. Among its 100 planets, WASP has found the largest known planet, the shortest-period hot Jupiter, the first planet found in a retrograde orbit, and planets spiralling into destruction on their host star.
Professor Coel Hellier, who leads the WASP-South teams says: "The WASP planets will be a mainstay of exoplanets research for decades. Astronomers worldwide are studying our planets."
The WASP project is the most successful of the teams searching for transiting exoplanets from ground-based observatories. The main competition is NASA's Kepler mission, which uses the same techniques but from space. As WASP announces planets numbering up to WASP-101, Kepler has found planetary systems as far as Kepler-88. The Kepler satellite recently stopped operating owing to a fault in its guidance system. Currently, WASP-South is continuing to scan the night sky, every clear night, from South Africa's Karoo desert.
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More information: BBC News link about 1000 exoplanets www.bbc.co.uk/news/science-environment-24549384