Gliese 581g lies in a zone called "the Goldilocks zone" or habitable zone [See related question]. It's an area in a planets orbit, where liquid water is likely to occur and thus harbour life.
It's not too hot or too cold. (As in the porridge)
It can also refer to a planet that is close to the size of the Earth.
Goldilocks Zone or Goldilocks Planet.
Because Gliese 581 g, if it exists, is located near the middle of the habitable zone (or Goldilocks zone - [See related question]) of its parent star.
3-6. The 3 planet model would have gliese 581 b too hot, gliese 581 c in the habitable zone, and gliese 581 d too cold. The 6 planet model would have gliese 581 e, b, and c too hot, gliese 581 g and d in the habitable zone, and gliese 581 f too cold.
Gliese 581 c is too hot for life because it is closer to its star. This planet is similar to venus. This planet traps too much heat that causes a strong greenhouse effect. The temperature is too high and the atmosphere is nearly all carbon dioxide. Gliese 581 d is at the right distance for liquid water to exist. It is at the Goldilocks zone just like the earth. That means life could exist on Gliese d. This planet have the right temperature. It has a magnetic field and a rich oxygen and nitrogen atmosphere.
Gliese 581 IS the system, D is the planet.
There are planets that are good candidates. There called Gliese 581 c and Gliese 581 d, they orbit a red dwarf 20.3 light years away. And they are thought to have an atmosphere and a temperature in which water may exist, and may also be in the "Goldilocks Zone."
gliese 581 is a star system not a planet however two of the 3 planets there are debatable that one of them could support life
No. g liese 581c is a planet that orbits a star, Gliese 581.
Earth is similar to Gliese 581 c, in that they both are the third planet from their sun. See related links for information about Gliese 581 c.
Planets are simply named by adding a letter to the host star name. The first planet found orbiting GJ 581 is called GJ 581 b (where A corresponds to the star). The 2nd discovered planet is GJ 581 c, and so on.
Gliese is a new planet discovered in April 27, 2007 but told in 2010.
The planet Gliece does not exist. Are you thinking of the Gliese 581 system?