The exoplanet discovered by Pennsylvania State University researchers is theoretically too large to orbit a small dwarf star. Scientists are trying to find out how such a planet could have been born.
Artist’s view. The planet LHS 3154b orbits a star too small in size to allow the birth of a planet of a similar size. Penn State
Scientists recently discovered a planet that, based on current theories, should not exist. The planet LHS 3154b orbits a star too small in size to allow the birth of a planet of a similar size.
News about the discovery, among other things Popular Mechanics.
In planetary systems, a group of planets and other celestial bodies revolve around a star under the influence of its gravity. There have been theories about the birth of planetary systems, of which the so-called accretion theory is the most popular.
The birth of the solar system has also been explained using the accretion theory. According to astronomers, a disc of gas and dust formed around the Sun. Smaller celestial bodies were initially created from the material, which collided with each other, eventually forming protoplanets, or nascent planets.
Theories should be re-examined
The size of a star at the center of a planetary system affects its gravity and, at the same time, how large planets it can attract. The exoplanet discovered by researchers is theoretically too large to orbit a small dwarf star.
– The planet-forming disk surrounding the low-mass star LHS 3154b is not expected to have enough solid mass to form that planet, researcher Suvrath Mahadevan says in the announcement.
According to Mahadeva, the discovery of a planet means that scientists have to re-examine the theories of the formation of planets and stars.
The exoplanet is 13 times larger than Earth. It is not an exceptionally large planet, because Jupiter, for example, is 316 times the mass of Earth.
What is special is that the planet orbits a cool dwarf star with a mass one ninth of the mass of the Sun. According to current models, a star of similar size should not have such a massive rotation.
Next, scientists have to explain how the planet could have formed. According to the researchers, in the composition of the disc formed around the star, for example, the ratio of dust to gas must be significantly higher than previously thought.
Investigator By Megan Delamer according to the observation is very rare.
– It is difficult to explain what we see with current theories of planet formation, says Delamer.
The observation was made with the HPF spectrograph (Habitable-Zone Planet Finder) located on Earth. The study has been published Science-in leaf.