http://gscim.com/Science_News/4-13/Exoplanets_Kepler-62e_Kepler-62f_Kepler-69c.html
The Kepler space telescope was found three so called super-earths that closes to being Earth like of any planets so far discovered called Kepler-62e, Kepler-62f and Kepler-69c. While these three worlds are the most earth like extrasolar planets found to date they are still far from being truly like the Earth. But evolutionary astronomers being ever hopeful are expressing increased confidence of eventually finding another planet with life on it.
Kepler-62e is about 1.6 times the size of the Earth and Kepler-62f is about 1.4 times the size of the Earth making it the smallest Habitable zone planets ever found. While they are with in their star's habitable zone it is also 20% dimmer than the sun and located 1,200 light years away.
Based on size they are probably rocky planets but that does not make them Earth like. Kepler-62e has a year of just 122 Earth days and Kepler-62f has a year of 267 Earth days, for comparison Venus has a year of 225 days. Now for these planets to have like Earth temperature they would have to have just the right amount of greenhouse effect from their atmospheres. Unless Kepler-62f has a high greenhouse effect any water on its surface would freeze and unless Kepler-62e has heavy clouds and little greenhouse effect it would be too hot for liquid water. So rather than being super-earths it is possible that Kepler-62e could be a super-venues and Kepler-62f could be a super-mars.
Kepler-69c is about 1.7 times and it is the smallest planet found with in the habitable zone of a sun-like star and it is about 2,700 light-years away however it's year is just 242 Earths days which is much closer to Venus' 225 Earth days than Earth's 365. In fact the above illustration shows that like Venus it is just on the inner edge of its star's habitable zone suggesting that it is most likely a super-venus rather than a supper-earth.
------ Charles Creager Jr.
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