Scientists have discovered an exoplanet the size of Neptune: its density is unlike any other
Astronomers have discovered a new exoplanet called TOI-332b. Its physical properties are difficult to explain using the modern theory of planetary formation. Science Alert writes about it. There are few exoplanets of this type in the Milky Way. In total, more than 5,500 exoplanets – worlds outside the solar system – have already been discovered. Their properties, such as radius or distance to the star, are usually common. But sometimes rare phenomena occur. They can become the key to the answer to the question: how exactly do planetary systems form and evolve? One of the regions of such rare phenomena is called the Neptunian desert – an area near the star where there are no planets the size of Neptune. But there is a small number of exoplanets located right in it. Photo: Illustrative. gremlin/Gettyimages.com The recently discovered TOI-332b at a distance of 727 light years from us fits exactly these characteristics. Measurements of the influence it exerts on the light of its host star show that its radius is 3.2 times that of Earth (Neptune is 3.88 Earth radii), and the planet orbits the star every 18.72 hours. But a team of astrophysicists led by Ares Osborne from the University of Warwick in Great Britain found out something else. Gravitational influence allowed her to measure the mass of the exoplanet. It reaches 57.2 Earth masses when Neptune’s mass is 17.15 Earth masses. This indicates that the density of TOI-332b is 9.6 grams per cubic centimeter. And that makes it one of the densest Neptunian exoplanets ever found. For comparison, Neptune has a density of 1.64 grams per cubic centimeter, while Earth has a density of 5.51 grams. The simulations also show that the exoplanet has a huge, dense iron core with a rocky mantle and a thin layer of helium and hydrogen. But there is no atmosphere like Jupiter. Currently, scientists are wondering where she went. This phenomenon cannot now be explained by either photoevaporation or planetary migration, which could lead to the loss of the atmosphere. One of the theories speaks of a gigantic impact on another object. It is suggested that TOI-332b may never have accreted an atmosphere at all. But this issue will be studied in more detail. “This unusual planet tests what we currently understand about planet formation; how such a giant core exists without a gaseous envelope remains an unanswered question,” the researchers write. Earlier we talked about the formation of a Jupiter-sized exoplanet around a tiny star. Read also: At NASA, with the help of the Webb telescope, an exoplanet the size of the Earth was studied
Original Source Link