Astronomers using the Spectro-Polarimetric High-contrast Exoplanet Research (SPHERE) instrument on ESO’s Very Large Telescope have discovered a giant exoplanet orbiting the young star YSES 2 directly.
A direct image of the massive exoplanet YSES 2b and its host. Image credit: ESO / SPHERE / VLT / Bohn et al.
YSES 2 is a K1 star that is 359 light-years away in the southern constellation Musca.
The star, also known as TYC 8984-2245-1, is only 13.9 million years old and belongs to a nearby group of stars called the Scorpius-Centaurus Society.
The newly discovered planet, named YSES 2b, has a mass about 6.3 times that of Jupiter and orbits its parent star at a distance of 115 AU (astronomical units).
“YSES 2b is an important addition to the sparsely populated group with large companions with a large gas,” said Alexander Bohn and colleagues.
The astronomers tracked the planet using the SPHERE instrument on ESO’s Very Large Telescope.
The discovery was made as part of the Young Suns Exoplanet Survey (YSES), which aims to locate and characterize companions of the planet’s mass to host stars of the sun in the Scorpius-Centaurus association.
“The great distance from YSES 2b to its star presents a mystery, as it does not appear to be one of the two best-known models for the formation of large gaseous planets,” the researchers said.
“If the planet in the present place had grown far from the star by means of nuclear wax, it would be too heavy because there is not enough material to make a large planet at this great distance from the star.”
“If the planet was created by so-called gravitational instability in the planetary disk, it does not appear to be heavy enough.”
‘A third possibility is that the planet formed near nuclear growth near the star and then migrated outward. ‘
“However, such a migration would require the gravitational influence of a second planet, which the researchers have not yet found.”
“By exploring more Jupiter-like exoplanets in the near future, we will learn more about the formation processes of gas giants around Sun-like stars,” Bohn concluded.
The discovery is reported in a paper in the journal Astronomy & Astrophysics.
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Alexander J. Bohn et al. 2021. Discovery of a directly imaged planet for the young solar analogue YSES 2. A&A 648, A73; doi: 10.1051 / 0004-6361 / 202140508