Scientists at the University of Oxford have unveiled a new “super Earth” exoplanet named HD 20794 d—situated just 19.7 light-years away in the Eridanus constellation. With a mass six times that of Earth, this rocky giant orbits its host star in an elongated path, venturing across the star’s habitable zone. Researchers believe the planet could retain liquid water, sparking hope that it may someday reveal signs of life.
A triumph of precision astronomy
Astronomers used the highly sensitive HARPS and ESPRESSO spectrographs in Chile to confirm subtle “wobbles” in the star’s light output—an indicator of an orbiting planet. Although NASA’s TESS satellite offered supporting data, the discovery was far from certain at first; signals were faint, hovering at the instruments’ detection limits. Ultimately, the team’s rigorous analysis confirmed HD 20794 d’s existence.
Prospects for alien life
While finding a planet in a star’s habitable zone is an encouraging sign, scientists caution that much remains unknown. The exoplanet’s elliptical orbit means it swings from the zone’s outer edge to the inner boundary, raising questions about its climate stability. Future missions will seek to determine whether HD 20794 d hosts an atmosphere or has any surface water—crucial factors for sustaining life.
The long road ahead
Despite its relative closeness on a cosmic scale, 19.7 light-years is far beyond current interstellar travel capabilities. Researchers hope emerging space telescopes will soon take direct images of this super Earth, potentially revealing more details about its composition and habitability. For now, HD 20794 d stands out as one of the most promising candidates in the ongoing search for extraterrestrial life.
