The exoplanet in question orbits the red dwarf star K2-155, which can be found approximately 200 light-years from Earth.
New research has confirmed the presence of 15 exoplanets orbiting smaller, cooler red dwarf stars.These include three so-called “super-Earths,” with one of them believed to have a key ingredient for life – liquid water.
In two studies recently published in the Astronomical Journal, the researchers on data from the Kepler space telescope’s K2 mission, which were combined with findings made using ground-based telescopes such as Spain’s Nordic Optical Telescope and Hawaii’s Subaru Telescope. This allowed them to confirm the 15 new exoplanets and their host stars, including K2-155, which is located around 200 light-years from Earth. Three super-Earths were found to be orbiting that bright red dwarf, but it was the outermost planet, K2-155d, that stood out as possibly being within K2-155’s habitable zone.
As noted by Phys.org, suggested that there is a chance that K2-155d, which has a radius about 1.6 times greater than our planet’s, might have liquid water on its surface. But while the researchers’ simulations further hinted at the exoplanet having an “Earth-like” atmosphere and other features, study lead author Teruyuki Hirano of the Tokyo Institute of Technology stressed that it isn’t 100 percent sure whether K2-155d is indeed a habitable super-Earth with at least some of the necessary ingredients for life.
With this important disclaimer in mind, the researchers added that more information needs to be gathered to truly confirm whether the super-Earth called K2-155d could support life or not. This includes more specific estimates of host star K2-155’s radius and temperature, which can only be determined through follow-up research, which, according to Phys.org, may require the use of interferometric techniques. But the two new studies still yielded substantial takeaways, including the observation that planets orbiting red dwarfs might be similar to those that orbit stars with similar characteristics to the sun, though they may be smaller in number than those that orbit “solar-type stars.”
“Red dwarf systems, especially coolest red dwarfs, are just beginning to be investigated, so they are very exciting targets for future exoplanet research,” said Hirano.
The research team found that the star K2-155d could potentially have liquid water on its surface based on three-dimensional global climate simulations.https://t.co/YDJsauNNCQ
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Hirano further commented on the finding that planets that orbit red dwarfs have a similar radius gap to planets orbiting solar-type stars, saying that his team’s discovery was “unique,” and that astronomers are currently trying to figure out the reason behind the radius gap. Furthermore, he speculated that photoevaporation, a phenomenon where electromagnetic radiation strips away a planet’s atmosphere, might be the reason why aren’t too many large planets close to their host stars, and that the metallic content of a host star could be linked to the size of the planets that orbit it.
Going forward, Hirano is optimistic that NASA’s Transiting Exoplanet Survey Satellite (TESS) would yield more information on potentially habitable super-Earths such as K2-155d. According to NASA’s overview page for the satellite, TESS will observe over 200,000 stars for their , or instances when a planet passes right in front of its host. The space agency also hopes to document over 1,500 transiting exoplanet candidates with TESS, including about 500 which could be classified as Earth-sized or super-Earth planets.