Megacolision away from the universe gives clues to planetary creation | Science and health

They believe that the cosmic event produced a world rich in iron, with nearly ten times the mbad of the Earth. A similar collision much closer to us would have led to the formation of the Moon 4.5 billion years ago.

The discovery was made by astronomers from the Canary Islands during the observation of a remote system of 1600 light-years. The studied planets revolve around a sun-like star called Kepler 107 in the constellation Cygnus.

It is believed that one of the planets, Kepler 107c, has an iron core representing 70% of its mbad, the remainder probably consisting of a rocky mantle.

Another planet near the star of this system, Kepler 107b, is 50% larger than the Earth, but its density is equal to half.

Scientists believe that the iron-rich planet was formed when it collided head-on at high speed with another object, which would have shed the clearest part of its outer layer.

They calculated that planets should travel more than 60 km / s at the moment of impact.

Zoë Leinhardt, a researcher at the University of Bristol in England and co-author of the study, explained that computer simulations were used to test theories.

"Before, there would be two objects where Kepler 107c is and they would have collided." Now there are only 107c, "she told BBC News.

" Another possibility is that 107c has been struck several times by smaller objects. The problem with this theory is: why did this happen only for 107c? It would be a little easier to understand if it was a single event, but does not mean it was just an event. "

Chris Watson of Queen's University in Northern Ireland led the research and said that this planetary system" would have been a violent place. "

We now see what's happening. he remains of this collision at high speed between two objects, he said.

"We found two planets in a very similar orbit, around the same star but with very different densities", a- he told BBC News.

"One is rocky, the other is made of a much denser material, probably iron. The only way to actually explain it is that, in one of them, a rocky surface was removed by collision. "

How Planetary Systems Are Formed

Another The theory – that the radiation of the star-mother would have sucked the gas from what would be planets the size of Neptune – was discarded, a process that would have made 107b denser than 107c and not the reverse.

The research published in the journal Nature Astronomy raises new questions about the formation and evolution of planetary systems in remote regions of the Universe.

Leinhardt explained that the planets in question probably formed at a point farther from the star, and then migrated, while the gravity of the star mother sucked gaseous material, a process known as accretion.

"At the moment of l & # 39; 39, accretion, the planets were crooked They were dragging and interacting with this gas disk – and they were moving too. As they moved, they were getting as close as possible, "he explained.