A new study by the scientists at NASA's Jet Propulsion Laboratory in Pasadena, CA suggests that one out of every 37 to one out of every 70 sun-like stars may have an Earth-like planet in it's orbit, according to Space.com. These planets are at such a position that liquid water could exist on the planet's surface, according to the researchers.
That means there could be billions of Earth-like planets just in the Milky Way Galaxy.
In February, the Kepler telescope identified 1,200 possible alien worlds, 68 of which were about the size of Earth. The new data, again collected by the Kepler telescope, suggests that 1.4 percent to 2.7 percent of all stars in the galaxy could be expected to have Earth-like planets in the appropriate zones, according to UPI.