That planet that was thought to have been found in the Goldilocks Zone of a nearby (only
20 light-years away!) may not actually exist due to lack of further evidence.http://news.discovery.com/space/gliese-581g-and-the-nature-of-science.html
Amid the breathless excitement of finding a potentially habitable exoplanet, there's been a bit of a buzzkill cropping up in the news. At an exoplanet conference in Turin, a Geneva-based team announced that they have not found evidence of Gliese 581g, casting a shadow of doubt on its discovery in the minds of some. What does this really mean?
The Geneva team used data from HARPS, or the High Accuracy Radial Velocity for Planetary Searcher, a powerful spectrometer on a 3.6-meter telescope in Chile. HARPS has been enormously successful at detecting exoplanets using the radial velocity method, or measuring the gravitational tugs on stars by their planets by watching the stars' spectral lines "wobble" back and forth due to the Doppler effect.