Gliese 251 is an early red dwarf star, ranking as the 74th closest star system to our Sun.
An artistic interpretation of the Gliese 251 system. Featuring Gliese 251c (left), its host star (right), and the already discovered planet Gliese 251b (center). Image credit: Michael Marcheschi / m2design.
You can find Gliese 251 as a bright M dwarf star, located at a distance of 5.58 parsecs (18 light years) in the constellation of Gemini.
Also known as GJ 251, HD 265866, or Wolf 294, this star is believed to host at least two super-Earths, Gliese 251b and Gliese 251c.
Initially discovered in 2020, Gliese 251b has a mass of 3.85 Earth masses and completes an orbit in 14.2 days.
The newly identified exoplanet, Gliese 251c, boasts a mass of 3.84 times that of Earth and has an orbital period of 53.6 days.
“With so many exoplanets now known, discovering new ones may not seem significant,” remarked Paul Robertson, an astronomer at the University of California, Irvine.
“The exceptional aspect is that its host star is nearby, roughly 18 light-years distant. From a cosmic perspective, it’s essentially in our neighborhood.”
Gliese 251c was detected using the Habitable Zone Planet Finder (HPF), a state-of-the-art near-infrared spectrometer mounted on the Hobby-Eberly Telescope at McDonald Observatory in Texas.
This planetary signal was subsequently validated using the NEID spectrometer at Kitt Peak National Observatory in Arizona.
Corey Beard, Data Scientist at Design West Technologies, states:
“While the discovery is statistically significant, we are still assessing the state of the planet due to instrument and methodological uncertainties.”
“Direct imaging of this candidate will rely on the next generation of telescopes and community investment.”
Given Gliese 251c’s closeness to Earth, it stands out as a prime candidate for future direct imaging studies utilizing the Thirty Meter Telescope (TMT).
The TMT, with its large mirror, could potentially directly image dim exoplanets like Gliese 251c and verify the presence of water.
“TMT is anticipated to be the only telescope capable of capturing such details. These images will pertain to exoplanets,” Dr. Beard added.
“Such imaging isn’t feasible with smaller telescopes.”
The results from the research team were published in Astronomy Magazine.
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Corey Beard et al. 2025. Discovery of a nearby super-Earth candidate located in the habitable zone, suitable for direct imaging. A.J. 170, 279; doi: 10.3847/1538-3881/ae0e20
Source: www.sci.news
