The NASA Transiting Exoplanet Survey Satellite (TESS) has made an interesting discovery in our galactic neighborhood, just 33 light-years away from Earth. This means that if we were to travel at 1/10 the speed of light, it would take approximately 330 years to reach this location.
During a meeting of the American Astronomical Society on June 15 in California, scientists identified a group of objects consisting of a host star and its orbiting planets, known as an exoplanetary system. Among them, there are at least two planets larger than Earth, referred to as super-Earths.
According to a press release by the Massachusetts Institute of Technology (MIT), the host star of this exoplanetary system is named HD 260655. It is a relatively small star, classified as an M-dwarf, or red dwarf, due to its cool temperature. In the Morgan Keenan spectral classification system, M-dwarfs are significantly smaller than the Sun. The central star of our Solar System belongs to the G-type main-sequence star group, which is larger than M-dwarfs but only comprises about 1/10 of them.
The inner planet of the HD 260655 system orbits its host star every 2.8 Earth days and is approximately 1.2 times the size and twice the mass of Earth.
On the other hand, the outer planet takes 5.7 Earth days to complete one orbit around its host star and is about 1.5 times the size and three times the mass of Earth. Both planets are considered rocky planets.
Michelle Kunimoto, a researcher at the Kavli Institute for Astrophysics and Space Research at MIT, mentioned that the two planets orbiting HD 260655 are suitable targets for studying their atmospheres due to the high brightness of their host star.
However, the research team emphasized that the newly discovered planets are not suitable for human habitation. Due to their proximity to the host star, their temperatures are too high to retain water.
According to the study, the inner planet of HD 260655 has a temperature of 436.6 degrees Celsius, while the outer planet has a temperature of approximately 286.6 degrees Celsius.
The TESS satellite, launched in April 2018, is dedicated to the mission of discovering exoplanets outside the Solar System. It operates by detecting the sudden decrease in light from stars, indicating the presence of a planet passing in front of them.
Therefore, when scientists observed an unusual decrease in light from HD 260655 in October 2021, after months of testing, they found two planets orbiting the star.
Avi Shporer, a member of the MIT research team, stated that it is entirely possible for there to be more than two planets orbiting this star.