Study Halves GJ 3378b Mass to 2.3 Earths, Boosting Liquid Water Odds
Updated
Updated · Forbes · Jun 30
Study Halves GJ 3378b Mass to 2.3 Earths, Boosting Liquid Water Odds
1 articles · Updated · Forbes · Jun 30
Summary
A new Astrophysical Journal study puts GJ 3378b at about 2.3 times Earth’s mass, down from roughly 5 Earth masses and making the nearby world a stronger candidate for liquid water.
That lower mass suggests the planet is more likely rocky and less likely to have a crushing atmosphere that would rule out surface water, while its 21-day orbit leaves it getting nearly the same starlight as Earth.
Scientists still see a major caveat: GJ 3378b circles a red dwarf closely enough that intense radiation could strip away any atmosphere, a key unknown for habitability.
Located 25 light-years away, the planet was identified in 2024 and sits in the star’s habitable zone; upcoming observatories including the Giant Magellan Telescope and Extremely Large Telescope could probe it for atmospheric or life signs.
Will new telescopes find signs of life on this nearby planet within the next decade?
Is this promising 'Super-Earth' actually a radiation-blasted wasteland?
GJ 3378b’s Revised Mass and Orbit: A Nearby Super-Earth on the Edge of Habitability
Overview
GJ 3378b is an exoplanet orbiting a small, dim red dwarf star about 25 light-years away. Red dwarf stars are prime targets in the search for habitable planets because their habitable zones are close to the star, making it easier to detect Earth-sized worlds. GJ 3378b’s host star is much smaller and dimmer than our Sun, which allows the planet to maintain temperate conditions even while orbiting nearby. Although GJ 3378b has been detected, its exact size, composition, and atmosphere are still largely unknown, making it an intriguing subject for future exploration.