Gliese 581cJune 19, 2007 at 12:30 pm | Posted in Uncategorized | Leave a comment
Most of us have by heard of Gliese 581 and 581c through media and internet. Even today I saw an artist’s impression on Gliese 581c: http://antwrp.gsfc.nasa.gov/apod/astropix.html. This link will take you to that image.
The parent star Gliese 581 is a red dwarf, and is 20.5 light years away from Earth, and is in the constellation Libra. According to the Gliese Catalogue of nearby stars, it is the closest star system with respect to earth.
Gliese 581 c is the first extrasolar planet believed to have a surface temperature similar to that of Earth. It is the smallest extrasolar planet around a main sequence star discovered to date. Its discovery was announced in April this year, and was published in Astronomy and astrophysics Journal.
If it is a rocky planet with a large iron core, and has a radius approximately 50% larger than that of Earth, and it has a stronger gravity than Earth. Its orbital speed and orbital radius are much less than those of Earth. It is on the warm edge of the habitual zone around its parent star. The atar will appear much larger from the planet’s surface and its surface heat will also be higher than that of Earth. As the planets atmosphere is as yet unknown its actual surface temperature cannot be ascertained. Liquid water could exist but no evidence has yet been found. Its tidal forces could be 400 times as strong as on Earth. Only the twilight zone of its surface could be habitable.
I could collect the above data from Wikipedia.