The newly discovered exoplanet Gliese 486 revolves around a dark red dwarf star 26 light years away, 1.3 times the size and 2.8 times heavier than Earth.
Gliese 486b only takes 1.47 days to orbit the host star. It is therefore the third closest planet to pass in front of the host star and the nearest planet orbiting the red dwarf with a measured mass. Gliese 486 represents about 30% of the mass of the Sun). In addition, the team also determined that Gliese 486b is more likely to have a surface temperature of around 430 degrees Celsius, cold enough for the atmosphere to exist, but also warm enough to study its atmosphere from afar.
The combination of these characteristics makes Gliese 486b an ideal target for studying the atmosphere of a rocky exoplanet, according to lead researcher Trifon Trifonov of the Max Planck Institute for Astronomy in Heidelberg, Germany. Trifonov and his colleagues detected Gliese 486b with a CARMENES spectrometer installed on a 3.5-meter-diameter telescope at the Calar Alto observatory in Spain. CARMENES searches the planets by radial speed, noting the slight fluctuations in the movement of the star caused by the gravitational pull of the planet. This device detects such an oscillation in the star Gliese 486.
The team then studied Gliese 486 with NASA’s Transitional Exoplanet Survey Satellite (TESS). TESS observed a gradation in Gliese 486, which confirmed the existence of an exoplanet in the system. Trifonov et al. Studied the characteristics of Gliese 486b using data from TESS and CARMENES, as well as information from another spectrometer called MAROON-X on the Gemini North telescope in Hawaii.
For example, they determined the mass of the exoplanet from radial velocity and dimension data from transient observations. These two figures in turn reveal the density of Gliese 486 b at about 7 g / cm3, equivalent to Earth (5.5 g / cm3). Therefore, this exoplanet is more likely to be composed of iron silicate like the Earth, according to research results published March 4 in the journal Science.
However, the near-Venus surface temperature makes Gliese 486b the ideal candidate for life to exist. Trifonov predicts that it is a hot, dry world, littered with volcanoes and rivers of lava. Due to its small orbit, Gliese 486b is affected by a tidal lock with one side always facing the parent star. But its proximity to Earth and many other characteristics also make it an excellent laboratory for learning about the atmospheres of exoplanets.
