Scientists have discovered a possible “super-Earth” less than 20 light-years away, offering new promise in the search for habitable worlds. The planet, named GJ 251 c, appears to be about four times as massive as Earth and is likely rocky. According to Penn State astronomer Suvrath Mahadevan, a co-author of the discovery paper published in The Astronomical Journal, the planet orbits within its star’s “habitable zone,” where liquid water – and possibly life –  could exist if suitable atmospheric conditions are present.

The finding is based on over two decades of observations and data analysis. Using the Habitable-Zone Planet Finder (HPF) – a high-precision, near-infrared spectrograph developed at Penn State and mounted on the Hobby-Eberly Telescope in Texas – researchers detected subtle “wobbles” in the star GJ 251’s light caused by orbiting planets. They first refined data on a known inner planet, GJ 251 b, then uncovered a second signal corresponding to a more massive planet with a 54-day orbit. The result was confirmed using Penn State’s NEID spectrometer at Arizona’s Kitt Peak National Observatory.

Detecting such faint planetary signatures requires advanced technology and data modeling to separate real planetary effects from stellar activity, such as starspots, which can mimic planetary motion. “It’s a difficult challenge, teasing out subtle signals from a turbulent star,” Mahadevan explained.

The discovery showcases the power of interdisciplinary collaboration combining astrophysics, engineering, and data science. Eric Ford, director of research at Penn State’s Institute for Computational & Data Sciences, emphasized that advanced statistical tools were key to distinguishing genuine planetary signals.

While GJ 251 c cannot yet be imaged directly, Mahadevan said upcoming 30-meter-class telescopes will likely be able to study its atmosphere for chemical signs of life.

For more details, read the full article by Penn State University.