Two new exoplanets give insights on how planets are formed

Astronomers have studied that two newly found exoplanets have similar sizes but very different densities and might give insights on how worlds are formed. Dubbed Kepler-107b and Kepler-107c have similar radii of 1.5 and 1.6 Earth radii, but they are twice our planet's density.

Scientists from Italy's National Institute for Astrophysics (INAF) and the University of Bristol in the UK have observed the Kepler-107 using the Telescopio Nazionale Galileo in La Palma. They collected a lot of spectroscopic measurements of all four sub-Neptune mass planets in Kepler-107.

Unlike Earth's relationship with the Sun, the planets in the Kepler-107 system are much closer to each other and their prime star. All the planets have an orbital period of days and not in years.

"Giant impacts are thought to have had a fundamental role in shaping our current solar system," said Zoe Leinhardt from the University of Bristol.

"The moon is most likely the result of such an impact, Mercury's high density may be also, and Pluto's large satellite Charon was likely captured after a giant impact but until now, we hadn't found any evidence of giant impacts occurring in planetary systems outside of our own," Leinhardt added.

"If our hypothesis is correct, it would connect the general model we have for the formation of our solar system with a planetary system that is very different from our own," he said.