CAJ 4: Breaking News: Kepler 186-f

On April 17th, NASA's Kepler Team announced the discovery of a planet in the habitable zone. This is a major step forward in the discovery of an Earth-like planet and a milestone for the Kepler Mission. Until recently, scientists only discovered  planets that were 40 % larger than Earth with similar properties but with the discovery of Kepler-186f, the Team can declare that there are planets similar to Earth in size and are in the habitable zone of their star, outside of our Solar system.

Kepler 186-f is claimed to be a rocky planet but scientists have to calculate the mass and density of the planet. Therefore, further analysis has to be done before drawing a conclusion. As the planet has the right size and is in the middle of the habitable zone of its star, the chance that it has liquid water is high. The temperature of the planet depends also on its atmosphere, for this reason it is not confirmed to be habitable yet.

 The planet is 500 light years away from us. The star that it orbits is half the size and dimmer than our Sun. Kepler 186f orbits its Star every 130 days. The star has  four  other planets ( Kepler186-b,c,d,e) that are all much closer to their Sun. They whiz around their Sun every 3 to 22 days, making them too hot to be habitable.

Scientists refer to Kepler186-f not as Earth-twin but as Earth-cousin. It has many properties that resemble Earth, but it gets less energy from its star than Earth gets from our Sun. On the surface of Kepler-186f the brightness of its star at high noon is only as intense as our Sun would appear for us an hour before sunset.

Only now I start to realize how important this Mission is. My CAJ topic brings, from day to day, new discoveries to light, which are in my eyes, very important historic events.