Extrasolar Planets: The Ongoing Saga
by Paul Deans
|This artist's concept shows the recently discovered planet Gliese 581g. It has a 37-day orbit right in the middle of the star's habitable zone, is only three to four times the mass of Earth, and has a diameter 1.2 to 1.4 times that of Earth. Artwork courtesy NASA / Lynette Cook.|
Two years after the launch of NASA’s Kepler mission, the discovery of extrasolar planets has turned from a trickle into a torrent. As a consequence of this data flood, other extrasolar planet researchers and facilities are often overlooked, and yet they continue to make discoveries or do critical work confirming Kepler's finds. There's a lot going on!
So every now and then I'll take press releases and Web items and assemble an article on exoplanets -- probably the hottest topic in astronomy these days. (Of course, exoplanet news items will continue to appear in "Astronomy in the News.") I'll include as many hotlinks as possible so you can keep tabs on the search, as astronomers seek the Holy Grail of extrasolar planets — an Earth-size, Earth-like world in a star's habitable zone.
And where better to start than with the complete press release announcing the detection of a remarkable six-planet system surrounding the star Kepler-11, followed by the discovery of a number of Earth-sized planet candidates in stellar habitable zones. Next, in an October 2010 release (that preceded this proliferation of planet discoveries), a NASA/JPL survey suggests that Earth-size planets may be quite common. Finally, discover how you can join the search for Earth-like worlds.
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