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As of 2007, the number of extrasolar planets detected stands at more than 200. Since the detection methods devised to date favor large, gaseous planets, most detected planets are quite dissimilar to Earth, and they are not thought to be good candidates for finding life. However, the planet [[Gliese_581c|Gliese 581c]] orbiting the red dwarf star Gliese 581 (approximately 20 light-years from earth) appears to be a terrestrial (that is, rocky) planet that orbits in the "habitable zone" of space surrounding its star. The term "habitable" in this context simply means that the stellar light flux it receives is similar to that of Earth, and it therefore might have an Earthlike temperature. Whether it is in fact habitable depends on many other factors, and is pure speculation at present.