Life may exist on one of the most recent planets to be discovered outside the solar system in 2010. Planet seekers have focused on a red dwarf star about 20 light years away called Gliese 581 which they suspected may offer a world comparable to Earth. A team of astronomers announced Wednesday that they had hit pay-dirt with the discovery of Gliese 581g, an Earthlike world in the star’s “Goldilocks zone,” an orbital distance where temperatures are considered suitable for life.
Finding the Goldilocks zone
Of the University of California, Santa Cruz, Steven S. Vogt took part in the announcement of Geliese 581g as the brand new planet found in 2010. Of the Carnegie Institute of Washington, R. Paul Butler also took place in this announcement. The New York Times reports that Gliese 581g (GLEE-za) makes an orbit every 37 days with a 14 million mile distance. It orbits the dim red star known as Gliese 581. Scientists say that is the sweet spot of the Goldilocks zone, where heat from the star isn’t too hot, not too cold, for water to survive in liquid form on the surface. When asked about life on Gliese 581g, Vogt said the chances “are almost 100 percent.”.
Life could be sustained by Gliese 581g
We know the star, Gliese 581, it only a third the size of the sun but is one hundred times brighter. It has six known exoplanets orbiting it, including Gliese 581g. A report on two of the Gliese 581 planets comes from Scientific Americans. It states the Goldilocks zone has these two exoplanets in it. Gliese 581g, about three times the mass of Earth, orbits between those worlds. The Goldilocks zone has never had an exoplanet discovered in it before. Now there is one. But it’s not exactly Earthlike. The planet hunter’s suspect Gliese 581g is “tidally locked,” which means only one side faces its star, like the moon does to Earth. Surface temperatures are expected to range from 31 below zero Fahrenheit on the night side to 158 degrees on the day side. Somewhere in between permanent daylight and permanent night, which Vogt called “eco-longitudes,” some form of life could become established.
Discovering exoplanets in just 2010
Gliese 581g was discovered using the radial-velocity, or “wobble,” technique. As explained in the Los Angeles Times, the wobble technique detects exoplanets by measuring a barely discernible gravitational tug they give their star during orbit. The Gliese 581 wobbles were indeed created by Gliese 581g because of brightness measurements the world seekers made.
Citations
New York Times
nytimes.com/2010/09/30/science/space/30planet.html?_r=1 and ref=science
Scientific American
scientificamerican.com/article.cfm?id=habitable-exoplanet-gliese-581
Los Angeles times
latimes.com/news/nationworld/nation/wire/sns-earth-like-planet,,7897054.story
