Bigger, a bit colder, but it could be one of the closest to earth-like planets discovered yet. Don’t get too excited just yet. This second earth, known as Kepler 186f, orbits a star that is more than 500 light years away. The discovery was made by NASA’s Kepler planet finding mission with the announcement coming Thursday April 17th, 2014. Now let’s get in to the gory details.

What Makes Kepler 186f A Second Earth?

First off, the size. Kepler 186f is extremely close to earth in terms of size. Only 10 percent larger than Earth, it has a diameter of 8,700 miles. The size of the planet also helps it secure the right gasses and elements to be earth-like. The announcement of Kepler 186f’s discovery follows last years announcement of 2 Earth-like planets. The problem with these planets is that they are too large; Super Earths. Being so massive means that they most likely have enough gravity to helium and hydrogen gasses. This leads scientist to believe that the planets are probably less like large Earths and more like mini Neptunes. Kepler 186f has a very close size to Earth, giving us more reason to believe that the make-up of the second Earth is rocky in nature, like the pale blue dot we call home.

Second, it’s location. Astronomers are often overly excited about planets found in the proposed “Goldilocks Zone.” The Goldilocks Zone is the area that is most likely conducive to harboring life. In lemans terms that means the planet must be just far enough from it’s start to not have it’s atmosphere evaporate, but not too far or the planet will be too cold to be habitable. Hence Goldilocks, it needs to be just right. The planet needs to be just warm enough to allow for liquid water. This gives us the best chance that life as we know it could develop. This possible second earth perfectly fits this criteria.

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An artist’s impression of a sunrise on Kepler 62f. The two outer planets of the Kepler 62 system may lie in the habitable zone, where liquid water could exist on the surface.

How Was The Second Earth Discovered?

Kepler has been watching over 150,000 stars for quite some time now. The way extraterrestrial planets are discovered is by examining the slight differences in light that occur when the planets cross over the stars from our view. When the planets are between us and the star, the light from the start gets slightly dimmer. “It’s a process” said Thomas S. Barclay of the Bay Area Environmental Research Institute. “This is a very, very exciting milestone discovery. It has a much higher probability of being habitable. This planet really reminds us of Earth.”

So How Close To Earth-Like Is It?

Close, but possibly no cigar.  Kepler 186f is different in quite a few and important areas. The star it orbits is a dwarf star that is smaller and cooler than our sun. The time it takes this second Earth to orbit it’s star takes only 130 Earth days. Remember that Goldilocks zone? Kepler 186f just makes the cut. Sitting at the edge of the Goldilocks zone, Kepler 186f receives far less star light causing it to be much colder. Probably not completely frozen though. If you love to spend your winters in Wisconsin, maybe now is the time to book your flight to Second Earth.

Stay tune to DevoutNone as we’ll have more information as this story develops.