Those who follow science news have probably seen many reports about the discovery of exoplanets, black holes and galaxies, but a protoplanet is a rare find for astronomers.
A protoplanet is, in fact, the embryo of a future planet that is in the early stages of formation. It appears in the protoplanetary disk (another name is the progeny) – a disk of dense gas and dust, which gradually merges into a system of planets under the influence of gravity. Scientists believe that something similar surrounded our Sun before the planets we know in the Solar System, including Earth, were formed.
Astronomers have been observing the star HD 169142 for several years, since they noticed that it is surrounded by a protoplanetary disk. Subsequently, a gap was seen in it, which confirmed the theories of scientists regarding the possible formation of a future planet in the region.
Further observations using the European Southern Observatory’s Very Large Telescope (VLT) instrument revealed an object moving through this gap at the speed at which a planet would move at such a distance from the star, so scientists received confirmation that it is a protoplanet. The object is also surrounded by dust, which may later merge into its satellites.
The planet, designated HD 169142b, is a gas giant with a mass roughly three times that of Jupiter. It rotates with a distance of 37 a. e. from its star is 37 times greater than the distance between the Earth and the Sun (≈149.6 million km). The rotation period of HD 169142b around the star is about 166 years. The system itself is located 371 light years from Earth in almost the same area as the Solar System in cosmological terms.
Two other confirmed protoplanets, PDS 70b and PDS 70c, discovered in 2018, are about 369 light years from Earth. They are gas giants, like HD 169142b, and they also have many times the mass of Jupiter.
Discoveries like this will help scientists better understand how Jupiter-like planets form. It will be recalled that a few days ago the European Space Agency launched the JUICE probe, which will search for microbial life in the sub-ice oceans of the planet’s satellites.
Source: Techspot
