Astronomers explain the formation of seven exoplanets around Trappist-1
Astronomers from the University of Amsterdam have offered an explanation for the formation of the Trappist-1 planetary system. The system has seven planets as big as the Earth that orbit close to their star. The crux, according to the researchers from the Netherlands, is the line where ice changes in water. Near that ice line, pebbles that drifted from outer regions to the star receive an additional portion of water and clot together to form proto-planets. The article with the model has been accepted for publication in the journal Astronomy & Astrophysics.
In February 2017, an international team of astronomers announced the discovery of a system of seven exoplanets around a small star, Trappist-1 (see report on eso.org). It was against the prevailing theories of planet formation that so many relatively large planets orbited so close around a small star. Researchers from the University of Amsterdam now come up with a model that explains how the planetary system could have originated.
Until now, there were two prevailing theories for the formation of planets. The first theory assumes that planets are formed more or less on the spot where they are now. With Trappist-1, that is unlikely because the disk from which the planets had originated should have been very dense.
Provided by: https://phys.org