Science – they discover the smallest planet in the process of formation

An international team of researchers has discovered a new planet at a very young age that it has not yet emerged from the “womb” of matter where it is formed; It is the smallest protoplanet discovered so far.

This Jupiter-like exoplanet – called AB Aurigae b – forms at a great distance from its star (93 times the average distance between Earth and our Sun); Its description was published in the journal Nature Astronomy.

According to scientists, its location and the patterns of matter surrounding it indicate the possibility of an alternative way of forming planets.

Specifically, the discovery supports the idea that giant planets could be made up of large chunks of gas that collapse through gravitational instability, rather than just the standard model used to explain Jupiter’s formation: core accretion.

In the Standard Model of planet formation, a large, Jupiter-like gas planet begins as a rocky core in a protoplanetary disk around a young star.

This core then accumulates gas from the disk and becomes a giant planet.

Although this model works well for planets in the solar system, it has trouble interpreting exoplanets that have been discovered around other stars at much greater distances than the orbit of Neptune, the farthest planet in the solar system.

The gas giant planets of the solar system, Jupiter and Saturn, orbit at a distance of 5 to 10 astronomical units (au) from the Sun, one of which is the average distance between the Earth and the Sun.

However, a small minority of giant exoplanets have been imaged at distances between 50 and 200 units from their stars. It is suggested that these exoplanets were created by a process known as disk or gravitational instability.

The researchers observed the formation of AB Aurigae b using the Subaru Telescope in Japan and the Hubble Space Telescope.

The team estimates its mass to be nine times that of Jupiter and suggests that several planets could orbit the host star.

“This study sheds new light on our understanding of the different ways planets form,” summarizes Thayne Currie, lead author of the paper.