Gliese 581c
Gliese 581c
An artist's impression of the exoplanet Gliese 581c orbiting its red dwarf star.
  • Gliese 581c is 20 light years from Earth.
  • The planet was discovered in 2007 using the radial velocity method of detection.
  • Gliese 581c is the third planet in order from its host star.
  • At the time of its discovery it was the smallest exoplanet detected around a main sequence star.
  • Gliese 581c orbits a red dwarf, the star has a mass around one third of that of the sun.
  • The planet is classed as a Super Earth, exoplanets which have up to 10 times the mass of our own planet.
  • Gliese 581c is most likely tidally locked, meaning one side of the planet is always facing its host star while the other is in constant darkness.
  • It is thought the planet's surface temperatures are similar to those on Venus.
  • Although originally thought to be in the habitable zone further research suggest its just outside, as a result it is highly unlikely life would be able to exist on the planet.
Gliese 581c compared to Earth in size
It is possible Gliese 581c has a diameter only 50% larger than that of Earth.
Gliese 581c Orbit
Gliese 581c revolves around its host star at a distance of only 6.8 million miles (11 million km) and takes only 13 days to make one complete orbit.
Gliese 581c Atmosphere
It is thought that Gliese 581c suffers from a runaway greenhouse effect due to its close proximity to its host star, which would give it a rather thick atmosphere similar to that of Venus.
Gliese 581c Mass and Radius
Gliese 581c is estimated to have a mass around 5 times that of Earth, if the planet is similar in composition to Earth its radius could be around only 50% larger than our own planet. If it has less density than Earth then it could have a radius 200% larger.
Gliese 581c Statistics

Host Star: Gliese 581
Host Star Type: Red Dwarf - M Class
Host Star Mass: 31% of Sun
Constellation: Libra

Distance from Earth: 20.3 light years
Planets Detected in System: 4 confirmed, 2 unconfirmed

Discovery Date: 24th April 2007
Detection Method: Radial Velocity
Exoplanet Type: Super Earth

Mass: 5 x Earth
Diameter: 50% to 200% greater than Earth depending on composition

Distance from host star: 6.8 million miles (11 million km)
Orbital Period: 13 days

Atmosphere: Possibly suffers from runaway greenhouse effect
Temperature: Unknown, possibly similar to the planet Venus.
Gravity: 125% to 225% of Earth's gravity depending on composition

Possibility of Life: Unlikely, orbits just outside habitable zone.