Using the Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has discovered three new exoplanets. All of them are so-called hot Jupiters — gas giants whose atmospheres are heated to extremely high temperatures.
The TESS telescope tracks 200,000 of the brightest stars in order to detect fluctuations in brightness caused by transits of their companions. Since the start of its mission in 2018, it has identified approximately 7,600 exoplanet candidates, of which 632 have been confirmed to date.
Now three more extraterrestrial worlds have been added to this list. A group of astronomers led by Yolanda Frensch of the Geneva Observatory in Switzerland reported the discovery of transit signals in the light curves of the orange dwarfs TOI-2969, TOI-2989, and TOI-5300. They are located at distances of 530, 635, and 530 light-years from Earth, respectively. The planetary nature of these signals was confirmed by subsequent ground-based observations.
With a mass approximately three times that of Jupiter, TOI-2989 b is the most massive exoplanet reported in the study. Its radius is 1.12 times greater than Jupiter’s, and its density is estimated at 2.7 g/cm³. The planet completes one orbit around its star in 3.12 days, with its orbit passing at a distance of 0.038 AU (5.7 million km) from it. The equilibrium temperature of TOI-2989 b was estimated at 730°C.
TOI-2969 b is approximately 10% larger and 16% more massive than Jupiter, giving it a density of about 1.1 g/cm³. The planet is located at a distance of about 0.026 AU (3.9 million km) from its parent star and has an orbital period of 1.82 days. Its equilibrium temperature is estimated at 910 °C.
TOI-5300 b is the smallest and least massive exoplanet of the three: its radius is about 0.88 times that of Jupiter, and its mass is only 0.6 times that of Jupiter, giving it an average density of about 1.1 g/cm³. The planet orbits TOI-5300 every 2.26 days at a distance of about 0.029 AU (4.3 million km) from it, and its equilibrium temperature, according to calculations, is 770 °C.
Based on the properties obtained, astronomers classified all three exoplanets as non-inflated hot Jupiters. The estimated mass of heavy elements in their interiors is significantly higher than in other known hot Jupiters orbiting orange dwarfs. In conclusion, the researchers note that the newly discovered exoplanets are good targets for further atmospheric studies, with TOI-2969 b being the most promising candidate.
Earlier, we reported on how astronomers measured wind speeds in the atmosphere of an ultra-hot Jupiter.
According to Phys.org
