Astronomers using a telescope Keck Observatory confirmed the existence of two protoplanets emerging from low-mass young star PDS 70, having received their direct image. The observations allowed us to estimate the mass of the protoplanet and the average rate of accretion of matter onto them, and calculate an approximate orbit. Article published in the journal The Astronomical Journal.
It is believed that the formation of planets occurs by two main mechanisms — long accretion of matter on the core or formation of gravitational instabilities in the protoplanetary disk. The details of these processes can learn from watching young or just emerging exoplanets (protoplanetary), however, due to the relatively short time of the formation of planets and lack of close to us young stars around which to find or residual protoplanetary disks, these studies are quite complex.
In 2018, astronomers reported on receiving the first ever direct image of a protoplanet, having a circumplanetary disk, in the system of low-mass young star PDS 70, which refers to type T Tauri is located at a distance of 370 light years from the Sun in the constellation of Centaurus. It is surrounded by a protoplanetary disk average radius of about 140 astronomical units.
In 2019 in the system was opened a second protoplanet, also surrounded by a circumplanetary disk and growing due to accretion. However, despite the fact that in PDS 70 was observed by several observatories, the data for a complete picture of the processes taking place in the system is not enough.
A group of researchers led by Jason Wang (Jason Wang) from the California Institute of technology published the results of observations of PDS 70 using the NIRC2 (Near Infrared Camera 2), equipped with a coronagraph and is installed on one of the 10-meter telescopes of the Keck Observatory equipped with an adaptive optics system. Their goal was determination of the parameters of protoplanets and their approximate orbits.