GJ 1214b
GJ 1214b waterworld
It is thought that GJ 1214b was once entirely covered in a warm ocean of liquid water.
  • GJ 1214b, also known as Gliese 1214b, is 42 light years from Earth and was discovered in November 2009.
  • GJ 1214b is classified as a water-world, and is the only example of such a planet yet to be discovered.
  • The planet orbits a small red dwarf star which has only 16% the mass of our own sun.
  • Its low mass suggests that unlike Earth GJ 1214b may only have a small amount of rock in its composition.
  • It is thought GJ 1214b once orbited in the habitable zone around its host star, which may have allowed life to exist in its warm oceans.
  • GJ 1214b is now a hot world with temperatures around 200C (392F)
  • Despite being hot its high atmospheric pressures would stop its oceans from boiling.
  • Water on GJ 1214b would now have a very strange consistency and would seem very alien to us, as a result of high temperatures and atmospheric pressure it would be more like thick hot ice or alternately acting more like a gas than a liquid.

GJ 1214b
GJ 1214b orbits very close to its parent red dwarf star.
GJ 1214b Orbit
GJ 1214b revolves around its host star at a distance of only 1.3 million miles (2 million km) and takes just one and a half days to make one complete orbit.
GJ 1214b Atmosphere
Analysis of the planet using the Hubble Space Telescope suggests GJ 1214b has a dense steamy atmosphere which is mostly composed of water vapor.
GJ 1214b Mass and Radius
GJ 1214b is estimated to have a mass of around 6 to 7 times that of Earth, with a radius of around 2.7 times that of Earth, its low mass suggests a large amount of the planet is made up of water. It is thought the planet originally formed as an ice world far from its host star.

GJ 1214b Statistics

Host Star: GJ 1214
Host Star Type: Red Dwarf - M Class
Host Star Mass: 16% of Sun
Constellation: Ophiuchis

Distance from Earth: 42 light years
Planets Detected in System: 1

Discovery Date: 17th November 2009
Detection Method: Transit Method
Exoplanet Type: Water World

Mass: 6 to 7 x Earth
Diameter: 2.7 x Earth

Distance from host star: 1.3 million miles (2 million km)
Orbital Period: 1.58 days

Atmosphere: A thick atmosphere primarily composed of water vapor.
Temperature: Around 200C (392F)
Gravity: 0.9 x Earth's gravity

Possibility of Life: Due to the lack of any water in its liquid form, combined with the high temperatures and pressure it is highly unlikely life could exist on GJ 1214b.