Gliese 581g: This rocky world was announced in September 2010. Gliese 581g, which is located just 20 light years away, is likely two to three times as massive as Earth and revolves around its parent star every 30+ days. This orbit places the planet squarely in the goldilock zone - that is the range of distances where liquid water and perhaps life as we know it, could exist.
Gliese 667Cc: Gliese 667Cc, which was discovered in Februrary 2012 by the same team that spotted Gliese 581g, orbits a red dwarf 22 light years away, in the constellation of Scorpius. The alien world is a so-called "super Earth". That's at least 4.5 times as massive as our planet and it completes a full orbit every 28 days. At least one other planet circles the star Gliese 667C, which is part of a triple-star system.
Kepler-22b: Kepler-22b was spotted by NASA's planet-hunting Kepler space telescope in December 2011. It is a super Earth about 2.4 times as big as our planet. If the greenhouse effect operates on Kepler-22b like it does on Earth, the alien world would have an average surface temperature of 72˚ F (22˚C), researchers calculated.
HD85512b: HD85512b is another super Earth, one that's thought to be 3.6 times as massive as Earth. The alien world is found about 35 light years away from us, in the direction of the constellation Vela (the sail). The planet's estimated surface temperatur is 77˚F (25˚C).
Gliese 581d: Gliese 581d is a world, which is about seven times as massive as Earth and orbits a bit farther out than its planetary sibling Giese 581g. When Gliese 581d was first discovered in 2007, many scientists regarded it as too cold to be potentially habitable. In the years since, atmospheric modeling studies have indeed suggested that the planet may be able to support life as we know it - provided the planet is warmed by a greenhouse effect.
Related Habitable Zone and Exoplanet Web Sites
- The NASA Exoplanet Archive
- The Exoplanet Data Explorer
- The Extrasolar Planets Encyclopaedia
- Habitable Zone Calculator
- Habitable Zones in Multiple Star Systems
- PlanetQuest: Exoplanet Exploration
- The Open Exoplanet Catalogue
- The Habitable Exoplanets Catalog
Related Habitable Zone and Exoplanet References
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- Hinkel & Kane, "Habitability of Exomoons at the Hill or Tidal Locking Radius", 2013, ApJ, 774, 27
- Jones & Sleep, "Habitability of exoplanetary systems with planets observed in transit", 2010, MNRAS, 407, 1259
- Kane, "Habitable Zone Dependence on Stellar Parameter Uncertainties", 2014, ApJ, 782, 111
- Kane & Gelino, "Detectability of Exoplanet Periastron Passage in the Infra-Red", 2011, ApJ, 741, 52
- Kane & Gelino, "The Habitable Zone Gallery", 2012, PASP, 124, 323
- Kane & Gelino, "The Habitable Zone and Extreme Planetary Orbits", 2012, AsBio, 12, 940
- Kasting et al, "Habitable Zones around Main Sequence Stars", 1993, Icarus, 101, 108
- Kopparapu & Barnes, "Stability Analysis of Single-planet Systems and Their Habitable Zones", 2011, ApJ, 716, 1336
- Kopparapu et al, "Habitable Zones Around Main-Sequence Stars: New Estimates", 2013, ApJ, 765, 131
- Selsis et al, "Habitable planets around the star Gliese 581?", 2007, A&A, 476, 1373
- Underwood et al, "The evolution of habitable zones during stellar lifetimes and its implications on the search for extraterrestrial life", 2003, IJAsB, 2, 289
- Zsom et al, "Toward the Minimum Inner Edge Distance of the Habitable Zone", 2013, ApJ, 778, 109