Scientists do not know why our solar system unusual

Since the time of Copernicus, scientists slowly saw the Earth from its predetermined "center of the universe." Today, scientists recognize that the sun - it is an ordinary star, not too hot, not too cold, not too bright, not too dim, located in a random place of the usual spiral galaxy. Therefore, when the telescope Kepler started his hunt for the world in 2009, scientists expected to find planetary systems which would have reminded our solar system.
Instead, Kepler discovered the types of planets, missing in our solar system. It turned out that exoplanets are much larger than we thought from the "hot Jupiters" (planets the size of Jupiter) to the "super-Earths" (massive rocky planets that are larger than our own). From 1019 and 4178 confirmed planet candidates discovered to date, only one system resembles our own: Earth-like planets close to a star, and the giant planets a little distance.
"We have no idea why our solar system unlike the others, and we would like to get an answer," - said planetary scientist Kevin Walsh of the Southwest Research Institute in Colorado Astrobiology Magazine.
In an attempt to compare the Sun and its planets with newfound stellar systems discovered by Kepler, a couple of astronomers suggested that the youth of our solar system may have contained as many as four planets orbiting closer to the Sun than Venus, and that after a series of catastrophic collisions survived only Mercury .
"One of the problems of our solar system is that by the standards of Kepler Mercury is too far from the Sun" - said planetary scientist Catherine Wolf of the University of British Columbia.
Wolf and her colleague Brett Gledmen from the same University, suggested that at the beginning of life of the majority of stars around them, "the system of densely packed inner planets» (STIP). Over time, the collision destroyed the set of planets, leaving them near 5-10% of stars observed today.
But although only a few of the observed systems contain STIP, Wolf believes that they once dominated - and the Sun could be one of these systems, the original of which was destroyed by the inner planets.
"If STIP formed with ease, perhaps they can be found all around the stars, after which 90% of those were destroyed," Wolf says.
Walsh did not participate in this study, but welcomes the work of Wolf compared the solar system from other planetary systems through the use of search patterns invisible planets, which could be in the past.