Planet Hunters

The first planet orbiting another star was discovered 14 years ago today. Since then, hundreds more have been identified

Today in 1995, French astronomers Michel Mayor and Didier Queloz made a stunning announcement: They had discovered the first extrasolar planet (or exoplanet -- a planet beyond our solar system orbiting around another star).

The star, 51 Pegasi, is over 50 light-years away, but it's quite similar to our Sun. The planet orbiting it is named 51 Pegas1 b. (All exoplanets that are the first discovered companion to their parent star are given the designation b.) Unofficially, the planet is known as Bellerophon, named after the ancient Greek hero who tamed the winged horse Pegasus and rode him to slay the Chimera.

Since the discovery of Bellerophon, 373 other exoplanets have been found, intensifying the debate about the possibility that one of these planets may support extraterrestrial life.

But most of the exoplanets that have been spotted so far are inhospitable gas giants like Jupiter. Part of the reason for that is the limitations astronomers have using ground-based observations.

The game is likely to change with NASA's Kepler Mission, which sent a special planet-hunting telescope into Earth's orbit earlier this year to find Earth-like planets in the habitable zone of stars in our galaxy.

Not only may these planets harbor alien lifeforms, they could be candidates for future human colonization. Human space exploration (beyond the Moon) is of course still firmly in the realm of science fiction. Perhaps getting on the back of a winged horse will have to suffice, at least for now.

GET INVOLVED

• Visit NASA's Kepler Mission page
  
• Participate in the International Year of Astronomy 2009
  
• Sign a petition to add the option for US taxpayers to contribute to NASA on the IRS 1040 tax form
• See what's in the sky tonight
• Buy a telescope from the Discovery Channel store

RELATED POSTS

• Kepler and the Gate to the Black Forest (February 15, 2009)
• Basic Chemistry of Life Found on Exoplanet (December 14, 2008)
• Where Stars Are Born (July 16, 2009)

image: artist rendering of 51 Pegasi b (image credit: Seth Shostak)