4 5 Billion Alien Earths May Populate Milky Way

Astronomers have found that 6 percent of all red dwarf stars have an Earth-sized planet in the habitable zone, which is warm enough for liquid water on the planet's surface. Since red dwarf stars are so common, then statistically the closest Earth-like planet should be only 13 light-years away. Image added Feb. 6, 2013. Billions of Earth-like alien planets likely reside in our Milky Way galaxy, and the nearest such world may be just a stone's throw away in the cosmic scheme of things, a new study reports. Astronomers have calculated that 6 percent of the galaxy's 75 billion or so red dwarfs - stars smaller and dimmer than the Earth's own sun - probably host habitable, roughly Earth-size planets. That works out to at least 4.5 billion such "alien Earths," the closest of which might be found a mere dozen light-years away, researchers said.For the rest of the story: http://www.livescience.com/26939-alien-earth-exoplanets-red-dwarfs.html