This event provides an opportunity to reflect on the possibility of life on planets around stars near our solar system.
Scientists have named this super-Earth Ross 508. According to NASA data, Ross 508 orbits a red dwarf star of type M. Its mass is four times that of Earth.
The green zone represents the habitable zone where liquid water could exist on the planet’s surface. Planetary orbits are shown as a blue line. Ross 508 b slides along the inner edge of the habitable zone (solid line) and may intersect the habitable zone for part of the orbit (dashed line). Source: Japan Center for Astrobiology
According to scientists, red dwarfs are easier to see at infrared wavelengths. Looking for evidence of planets surrounding red dwarf stars, the Center for Astrobiology in Japan has created an infrared observatory mounted atop the Subaru telescope — it’s a Doppler instrument. infrared (IRD) on Subaru’s 8.2-meter telescope – performs Ross 508’s radial velocity (RV) measurements.
The first result of this search is a sign of a super-Earth with four times the mass of Earth, orbiting the red dwarf star Ross 508, 37 light-years away, in the constellation Serpens.
This planet, Ross 508 b, has a year of only 10.8 Earth days and lies on the inner edge of the “habitable zone” (Goldilocks) around its parent star. Despite being quite close to the Ross 508 dwarf star, because the red dwarf is small and quite cool, the “habitable zone” of the planet Ross 508 b is also closer than Earth’s “habitable zone” – our sun.
The Japanese Subaru Telescope.
Interestingly, the scientists initially noticed that there is some evidence that the orbit is elliptical, meaning that the planet Ross 508 b will be in its habitable zone for part of its orbit — regions where conditions are right for liquid water on the planet. planet. surface. Whether there really is water or life are questions that need further investigation.
It will also be an important target for future observations to study the possibility of life around low-mass stars, such as the M dwarf it orbits.
The exact orbital eccentricity of Ross 508 b is unknown. Further studies of this could provide important information about the planet’s origin.
CHARACTERISTICS OF THE RED STAR
The parent star Ross 508 has a radius of about 0.21 solar rays and a mass of about 0.18 solar masses, giving it a density of 26.5 g/cm3.
The parent star Ross 508 has a radius about 0.21 that of the Sun.
Red dwarfs make up three quarters of the stars in our Milky Way galaxy and occur in large numbers near the solar system, making them an excellent target for searching for exoplanets near us.
Three quarters of the stars in the Milky Way are red dwarfs, smaller than the Sun and abundant in the vicinity of the Sun. They are therefore a prime target in the hunt for nearby extrasolar planets and extraterrestrial life. Red dwarfs are cooler than other types of stars and produce less visible light, making them difficult to study.
Bun’ei Sato, professor at Tokyo Institute of Technology (Japan) and principal investigator of this search, noted: “It’s been 14 years since IRD started developing. We have continued to develop it. developed and studied in hopes of finding a planet exactly like Ross 508. Our discovery shows that searching for near-infrared RVs can play an important role in finding a low-mass planet around cool M dwarfs like Ross 508”.
With such a promising initial discovery, we can expect the Subaru telescope to find more, perhaps even better, candidates for habitable planets near the red dwarf future.
The term “super-Earth” refers to planets with a mass greater than Earth, but no greater than the mass of Neptune. While the term “super-Earth” refers only to the mass of the planet, it is also used by astronomers to describe planets larger than Earth, but smaller than the so-called “mini-Neptune”. (with a radius of two to four Earths).
Source: Scitechdaily, NASA/Exoplanets
