Not so long ago there were no other planets around other stars known. Now we have over 1,500 and thoussands more candidates. The Kepler now has over 1000 confirmed planets to its credit.
So far out of all those Kepler planets, eight are less than Earth sized and are inside of the habitable zones of their parent stars. So not only are they warm enough for life like we know it, the size of the planet means the atmosphere could have similar charateristics to our own thanks to gravity. That isn’t to say they actually do, just that the potential is there. I would like to think eventually those atmospheres will be charachterized. In the mean time the search continues.
How many stars like our sun host planets like our Earth? NASA’s Kepler Space Telescope continuously monitored more than 150,000 stars beyond our solar system, and to date has offered scientists an assortment of more than 4,000 candidate planets for further study — the 1,000th of which was recently verified.
Using Kepler data, scientists reached this millenary milestone after validating that eight more candidates spotted by the planet-hunting telescope are, in fact, planets. The Kepler team also has added another 554 candidates to the roll of potential planets, six of which are near-Earth-size and orbit in the habitable zone of stars similar to our sun.
Three of the newly-validated planets are located in their distant suns’ habitable zone, the range of distances from the host star where liquid water might exist on the surface of an orbiting planet. Of the three, two are likely made of rock, like Earth.