Earth-sized Potentially Habitable Planet Discovered
For untold eons, humanity has wondered if we are alone in the Universe. Though we have not yet found alien life, we have been looking for places it may reside. Recently researchers from multiple institutions have found the first Earth-sized planet within the habitable zone of its sun.
The habitable zone covers the range of orbits about a star where the temperature is not too cold to freeze water into ice, or boil it off. Naturally our interest in the habitable zones come from the reliance life on Earth has on liquid water and an assumption that other life in the Universe also requires it. The host star for this planet is Kepler-186, the planet is named Kepler-186f, and both are located 500 light years away in the constellation Cygnus. The star is actually an M1-type dwarf star, which makes it cooler than the Sun, and is over five hundred thousand times dimmer than the stars we can see with the naked eye. It also has other planets in its orbit, these are much closer to it though and therefore much hotter.
Finding the planet required putting multiple observatories to work, including the Kepler spacecraft and the two terrestrial telescopes, Gemini North and Keck II. Kepler detected the planet by measuring the small dip in brightness it causes as it transits in front of the star. As many objects could cause such dimming, the other telescopes were employed to closely examine the system within 400 million miles of the star, to ensure that only a planet in the habitable zone could be the cause. Combining the data with calculations gives the researchers 99.98% confidence in this conclusion.
Source: Gemini Observatory