Analysis of data collected by the TESS space telescope has revealed two more previously unknown exoplanets. They orbit the orange dwarf TOI-836, which is quite close to the Sun.
TOI-836 is located 90 light-years from Earth. The star has a low level of metallicity. Its age is estimated at 5.4 billion years, and its mass and radius are about a third less than solar.
During the observations, TESS was able to detect periodic decreases in the brightness of TOI-836, corresponding to the presence of two invisible companions. Later, astronomers were able to determine their size and mass.
Hot super-Earth and mini Neptune
The exoplanet TOI-836 b, which is closer to the star, is a super-Earth. Its radius is 1.7, and its mass is 4.5 times the mass of our planet (this gives an average density of 5.02 g/cm3). The orbit of TOI-836 b lies at a distance of only 6 million km from its star, it takes 3.8 days for one rotation. The equilibrium surface temperature of the exoplanet is estimated at 500 °C.
The second exoplanet TOI-836 c was classified as a mini Neptune. Its radius is about 2.6 times, and its mass is 9.6 times greater than our planet. This gives an average density of 3.06 g/cm3, which indicates the presence of a large amount of light substances in its composition. The orbit of TOI-836 c lies at a distance of 11.2 million km from its star, it makes one rotation in 8.6 days. The equilibrium surface temperature of the exoplanet is estimated at 390 °C.
It is worth noting that astronomers have found variations in transit time TOI-836 с. This indicates that other, as yet undiscovered, exoplanets may exist in this system.
Recall that the TESS telescope recently discovered an ocean planet.
According to https://phys.org
Follow us on Twitter to get the most interesting space news in time