Two planets outside the solar system have been identified orbiting a star located nearly 250 light-years away from Earth in the Draco constellation. These planets are categorised as a super-Earth and a sub-Neptune. Both types are commonly observed in the Milky Way galaxy yet neither is present in our solar system. The host star, known as TOI-1453, is slightly cooler and smaller compared to the Sun. These planets were found around a binary star system which features two stars orbiting each other.

Details of the discovery

According to the study published in the journal Astronomy & Astrophysics these exoplanets have been named TOI-1453 b and TOI-1453 c. Their detection was carried out using data from NASA’s Transiting Exoplanet Survey Satellite and the High Accuracy Radial Velocity Planet Searcher for the Northern hemisphere spectrograph based in Spain. The TESS satellite identified these planets through the transit method which monitors reductions in a star’s brightness when a planet passes in front of it. Complementary measurements were obtained through the HARPS-N spectrograph which detects shifts in a star’s light caused by the gravitational pull of orbiting planets.

Characteristics of TOI-1453 b and TOI-1453 c

As per information shared by the University of Liège astrophysicist Manu Stalport, TOI-1453 b is categorised as a super-Earth slightly larger than Earth and believed to be rocky. It completes an orbit around its star in just over four days suggesting that it is extremely close to its host star. The planet’s proximity is likely to make its surface temperature very high.

In contrast, TOI-1453 c has been classified as a sub-Neptune and is nearly twice the size of Earth. Its mass is comparatively low at approximately 2.9 Earth masses which has raised questions about its density and composition. Astronomers believe that it may contain a hydrogen-rich atmosphere or a water-dominated interior.