Aldaron, a.k.a. Aldaron, CC BY-SA 3.0Gliese 581 g
also named ZarminaThe 'first habitable planet' that probably never existed
Overview
Gliese 581g was a candidate exoplanet postulated to orbit within the Gliese 581 system, twenty light-years from Earth. It was discovered by the Lick–Carnegie Exoplanet Survey, and was the sixth planet claimed to orbit the star; however, its existence could not be confirmed by the European Southern Observatory (ESO) / High Accuracy Radial Velocity Planet Searcher (HARPS) survey team, and was ultimately refuted. It was thought to be near the middle of the habitable zone of its star, meaning it could sustain liquid water—a necessity for all known life—on its surface, if there are favorable atmospheric conditions on the planet.
Source: Wikipedia
Why it matters
- Announced in 2010 as a 3-Earth-mass planet in the habitable zone of a nearby red dwarf.
- Other teams could not recover the signal; a 2014 study attributed it to stellar activity.
- A cautionary tale about radial-velocity noise; the NASA archive no longer lists it as a planet.
Discovery & system
- Discovered
- 2010 · RV
- Discoverers
- Steven S. Vogt
- Host star
- Gliese 581
The system
| World | Period | Distance | Radius | Mass | Temp. |
|---|---|---|---|---|---|
| Gliese 581 g | 36.5 d | 0.146 AU | — | 3.1 M⊕ | 231 K |
By the numbers
- Mass
- 3.1 M⊕18.51 ×10²⁴ kg
- Orbital period
- 36.5 d0.1 yr
- Distance from star
- 0.146 AU22 million km
- Eccentricity
- 0nearly circular
- Equilibrium temp.
- 231 K-42 °C
- Distance from Earth
- 20.3 ly6.2 pc
Sources
Image: Aldaron, a.k.a. Aldaron, CC BY-SA 3.0 · CC BY-SA 3.0 · image page
Text: Wikipedia (CC BY-SA 4.0). Taglines and highlights are editorial.