The ancient Greek mathematician Metrodorus (400-350 B.C.) explained that a universe where Earth is “the only world” is about as realistic as a “large field containing a single stalk.”About 2,000 years far along, in the 16th century, the Italian philosopher Giordano Bruno proposed something similar.
He said that countless suns and countless piles of Earth existed somewhere else, all rotating around their own suns exactly as the solar system Planets do.Experts now know that both Metrodorus and Bruno were basically correct. Today, astronomers are still exploring answers to this question, using newer and advanced tools.
There is now an evidence that validates the existence of exoplanets – Planets that are orbiting stars other than the Sun of the solar system.That suggestion is based on the discoveries made by the Kepler space telescope, launched by NASA in 2009.For four long years, the telescope watched uninterruptedly at a single section of the space within the Cygnus constellation.
Looking out from the Earth, it is an area that takes up less than 1% of the entire view of the sky.Kepler had 42 cameras involved, similar to the kind of smartphone cameras used to take pictures. In that one region, the telescope sensed the presence of more than 150,000 stars.For most of the stars, the amount of light stayed pretty much the same, while it changed roughly every half an hour for others.