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At least 50 billion planets "decorate" the Milky Way (vids)

Eventually, the man is just a grain of sand. When you consider how small the Earth thanother planets and the Sun.
When you consider how small is the Sun of our galaxy than others.

The astronomical number of 50 billion planets, of which about 500 million in the famous "habitable zone", according to the latest estimates of scientists.
NASA: Eventually there may even aliens
William Borouki, chief scientist of the mission of the Space Telescope «Kepler» of NASA, looking for planets, said estimates of the number of planets in our galaxy sample based on the first results of the «Kepler», which means a limited time and focusing on a small portion of the night sky (only 1 / 400), has already found hundreds of potential exoplanets.
The Borouki and his colleagues estimate that one in two stars in our galaxy (estimated at about 100 billion overall) has at least one planet around it, so there are a total 50 billion planets, which may however be much more, since it is natural many stars have more than one planet. Also, it is estimated that one in 200 stars have planets orbiting in the "habitable zone" (hence the number of 500 million potentially habitable extrasolar planets).
Indeed, it is possible the stars of our galaxy is much more than 100 billion, and estimates a Yale University scientist may eventually be three times (around 300 billion), so in this case is multiplied as the number of exoplanets .
According to statistical estimates Borouki, 10.5% of stars in our galaxy have planets approximately the size of the Earth (ie 50% to 125% on our planet), the 7.3% fall in the category of " super-Earth "(with size 125% to 200% relative to the Earth), 20.8% are the size of Neptune (two to six times higher than the Earth) and 5.2% have at least the size of Jupiter (more than six times larger than the Earth).
So far the "Kepler" has identified 1,235 potential exoplanets, of whom 54 are in the "habitable zone" where the existence of some form of life could be possible. Cross-checking and confirmation of the existence of extrasolar planets from other telescopes, will follow in the coming years.

A Look at the Milky Way Galaxy's Birth