A team of Swiss astronomers has identified six extrasolar planets that orbit in the opposite direction to the rotation of their star . The finding, presented at the National Astronomy Meeting of the British Royal Society to be held this week in Glasgow, Scotland, poses a challenge to current theories about planetary formation .
Until now, it was believed that all planets were formed from a disk composed of gas and dust, known as a protoplanetary, which revolves around a star in the same direction, as occurs in our solar system. However, when the Wide Angle Planet Finder (WASP) detected 9 new exoplanets and the astronomers compared them with a larger sample of 27 others, they found that 6 had a "retrograde motion" , that is, they orbited in the direction " wrong ", contrary to the star. In addition, they were exoplanets of the "hot Jupiter" type (gas giants that orbit very close to their main stars), whose origin has been a puzzle for the scientific community.
"We are dropping a real bomb in the field of extrasolar planets," said Amaury Triaud, a scientist at the Geneva Observatory and co-author of the study.
According to the scientists, a possible explanation for the "rebellious" behavior of these exoplanets would be a gravitational "tug of war" with more distant stars or planets , in a process that would last hundreds of millions of years.
