Extrasolar Planets
An extrasolar planet, or exoplanet, is a planet beyond the Solar System, orbiting around another star. As of December 2008, 333 exoplanets are listed in the Extrasolar Planets Encyclopaedia. The vast majority have been detected through radial velocity observations and other indirect methods rather than actual imaging. Most exoplanets are massive gas giant planets thought to resemble Jupiter, but this is a selection effect due to limitations in detection technology. The forthcoming NASA Kepler Mission will search for exoplanets using a completely different technique: planetary transits. It is estimated that at least 10% of sun-like stars have planets, and the true proportion may be much higher. The discovery of extrasolar planets sharpens the question of whether some might support extraterrestrial life. Currently, Gliese 581d, the third planet of the red dwarf star Gliese 581 (approximately 20 light years from Earth), appears to be the best example yet discovered of a possible terrestrial exoplanet that orbits close to the habitable zone surrounding its star.
-
Featured News
A Little Telescope Goes a Long Way
PASADENA, CA (Feb. 9, 2010) – NASA astronomers have successfully demonstrated that a David of a telescope can tackle Goliath-size questions in the quest to study Earth-like... More »
-
Featured News
In All the Universe, Just 10 Percent of Solar...
WASHINGTON, DC (Jan. 5, 2010) – In their quest to find solar systems analogous to ours, astronomers have determined how common our solar system is. They’ve concluded... More »
-
Featured News
NASA's Kepler Space Telescope Discovers Five...
PASADENA, CA (Jan. 4, 2010) – NASA's Kepler space telescope, designed to find Earth-size planets in the habitable zone of sun-like stars, has discovered its first five new... More »
-
Featured News
First Direct Observation of a Planet-like...
PRINCETON, NJ (Dec. 3, 2009) – An international team of scientists that includes an astronomer from Princeton University has made the first direct observation of a... More »
-
Featured Article
SIM PlanetQuest
SIM (Space Interferometry Mission), scheduled for launch within the next decade, will be the most powerful planet-hunting space telescope ever devised. Using two separated mirrors... More »
-
Featured News
Simulation suggests rocky exoplanet has...
Washington Univ., St. Louis (Oct. 1, 2009) – So accustomed are we to the sunshine, rain, fog and snow of our home planet that we find it next to impossible to imagine a... More »
-
Featured News
NASA's Spitzer Spots Clump of Swirling...
NASA-JPL (Sep. 24, 2009) – Astronomers have witnessed odd behavior around a young star. Something, perhaps another star or a planet, appears to be pushing a clump of... More »
-
Featured News
First Solid Evidence for a Rocky Exoplanet
ESO (Sep. 16, 2009) – The longest set of HARPS measurements ever made has firmly established the nature of the smallest and fastest-orbiting exoplanet known, CoRoT-7b, revealing... More »
A Little Telescope Goes a Long Way
Last Updated on 2010-02-09 at 17:35
PASADENA, CA (Feb. 9, 2010) – NASA astronomers have successfully demonstrated that a David of a telescope can tackle Goliath-size questions in the quest to study Earth-like... More »
In All the Universe, Just 10 Percent of Solar Systems...
Last Updated on 2010-01-05 at 17:21
WASHINGTON, DC (Jan. 5, 2010) – In their quest to find solar systems analogous to ours, astronomers have determined how common our solar system is.
They’ve concluded... More »
NASA's Kepler Space Telescope Discovers Five Exoplanets
Last Updated on 2010-01-05 at 17:12
PASADENA, CA (Jan. 4, 2010) – NASA's Kepler space telescope, designed to find Earth-size planets in the habitable zone of sun-like stars, has discovered its first five new... More »
Avatar's Moon Pandora Could Be Real
Last Updated on 2009-12-18 at 12:33
CAMBRIDGE, MA (Dec. 18, 2009) – In the new blockbuster Avatar, humans visit the habitable - and inhabited - alien moon called Pandora. Life-bearing moons like Pandora or the... More »
First Direct Observation of a Planet-like Object...
Last Updated on 2009-12-03 at 16:48
PRINCETON, NJ (Dec. 3, 2009) – An international team of scientists that includes an astronomer from Princeton University has made the first direct observation of a... More »
Exoplanet: Atmosphere
Last Updated on 2009-11-09 at 18:05
An "exoplanet" is an extra-solar planet, that is, a planet orbiting a star other than our own sun. Of the roughly 307 currently known extrasolar planets, about thirty of... More »
-
Articles -
Blog Posts -
Galleries -
News -
Resources -
Videos
- Include Content from all Sub-Sections
| Type | Title | Author | Date |
|---|---|---|---|
| Retrieving data... | |||

Site Options