Nearby Super-Earth GJ 251 c Becomes Key Focus in Search for Life

A team of astronomers at the University of California, Irvine, has identified a new super-Earth located within the habitable zone of an M-dwarf star, just 18 light-years from Earth. This discovery positions the exoplanet, named GJ 251 c, as a promising candidate in the ongoing search for extraterrestrial life, primarily due to its potential to support liquid water—a critical component for life as we know it.

Significance of GJ 251 c’s Discovery

Researchers reported their findings in a paper published in The Astronomical Journal. Co-author Paul Robertson, an associate professor of physics and astronomy at UC Irvine, emphasized the importance of the planet’s proximity. “Cosmically speaking, it’s practically next door,” he said, highlighting the advantages of studying a planet so close to our solar system.

GJ 251 c is classified as a super-Earth due to its mass being several times greater than that of our planet. It orbits an M-dwarf star—one of the most common and oldest types of stars in the Milky Way. These stars often exhibit significant activity, such as starspots and flares, which can complicate the detection of orbiting planets. Nevertheless, the relatively close distance of GJ 251 c makes it a prime target for future observations using advanced telescopes.

Advanced Instruments and Future Observations

The planet was detected using data from two high-precision instruments, the Habitable-zone Planet Finder and NEID. These tools measure the gravitational influence of the planet on its star, resulting in subtle shifts in the star’s light known as radial velocity signatures. The research team utilized these signatures to confirm the existence of GJ 251 c. The instruments are designed to minimize the interference caused by the star’s activity, particularly by observing in the infrared, where disruptive signals are weaker.

According to Corey Beard, lead author of the study and former graduate student in Robertson’s group, the Thirty Meter Telescope (TMT), currently under development, will have the capability to directly image faint exoplanets like GJ 251 c. “TMT will be the only telescope with sufficient resolution to image exoplanets like this one,” Beard stated, underscoring the limitations of smaller telescopes.

The findings raise hopes for further exploration of GJ 251 c, as the TMT could provide crucial insights into the planet’s atmosphere and potential for liquid water. “We are at the cutting edge of technology and analysis methods with this system,” Beard noted, while also emphasizing the need for community investment in upcoming research initiatives.

Collaboration has been a key aspect of this research, with contributions from scientists including Jack Lubin from UCLA, Eric Ford and Suvrath Mahadevan of Pennsylvania State University, Gudmundur Stefansson from the University of the Netherlands, and Eric Wolf from the University of Colorado, Boulder. The study received support from NSF grant AST-2108493 for the HPF exoplanet survey, alongside funding from NASA and NSF for the NN-EXPLORE program.

As the astronomical community looks forward to the operational readiness of the TMT and other next-generation telescopes, the discovery of GJ 251 c stands as a significant milestone in the quest to uncover life beyond our planet.