Venus Has Ozone Layer, Too

Venus has joined Earth and Mars in the ozone layer club. A spacecraft from the European Space Agency detected a thin layer about 60 miles above the planet, reports the BBC. Ozone protects Earth from the sun's ultraviolet rays, and astronomers say the discovery could help fine-tune their hunt for life on other planets.

"This ozone detection tells us a lot about the circulation and the chemistry of Venus' atmosphere," says an ESA scientist. "Beyond that, it is yet more evidence of the fundamental similarity between the rocky planets, and shows the importance of studying Venus to understand them all." (More Venus stories.)