Spanish astronomers have confirmed a new exoplanet, TOI-1752 c, within the habitable zone of a red dwarf star 337 light-years from Earth, alongside a world of lava planet in the same system, according to the Andalusian Institute of Astrophysics (IAA).
The discovery, made using NASA’s TESS satellite, reveals a two-planet system orbiting a red dwarf star. One planet, TOI-1752 c, is described as potentially habitable
due to its size, temperature, and possible atmospheric composition, while the other, TOI-1752 b, is a world of lava with extreme surface conditions. Both were identified through the telltale small, periodic dips in a star’s brightness caused by planetary transits, a method detailed by the IAA.
A Dual-Planet System
TOI-1752 c, larger than Mars but smaller than Neptune, lies within the optimistic habitable zone,
where liquid water could exist under certain conditions. Its temperature of 18°C (291K), 32-day orbital period, and potential for a gas-dominated atmosphere make it a twin of the previously discovered exoplanet K2-18 b, which contains carbon molecules. The IAA noted that TOI-1752 c may retain a larger proportion of its atmosphere following composition analysis, a factor that could influence its habitability [source].
The second planet, TOI-1752 b, orbits closer to its star, completing an orbit in less than a day. Its extreme heat, likely keeping its surface molten on the star-facing side, suggests a lava-world environment. Researchers speculate that its intense radiation could generate a secondary atmosphere from surface materials, though this remains unconfirmed [source].
Comparing TOI-1752 c to K2-18 b
Both TOI-1752 c and K2-18 b orbit red dwarf stars, have orbital periods of over 30 days, and reside in their respective stars’ habitable zones. However, TOI-1752 c’s moderate temperature and potential for atmospheric retention distinguish it as a promising candidate for further study. Scientists expect it to prove just as scientifically compelling as K2-18 b in the coming years, despite ongoing debates about its habitability [source].
While K2-18 b’s carbon molecules have made it a most promising target for Earth-like life, TOI-1752 c’s similarities to it—such as size and orbital characteristics—could offer new insights into the diversity of potentially habitable worlds. The Spanish-led team, which confirmed the discovery, emphasized that both planets are large enough to likely harbour atmospheres,
a key factor in assessing habitability [source].
The next steps for researchers involve deeper atmospheric analysis of TOI-1752 c to determine if it truly supports liquid water or complex chemistry. While the planet’s optimistic habitable zone status is encouraging, scientists caution that the presence of liquid water does not guarantee habitability. The discovery also raises questions about the prevalence of such systems in the galaxy and the conditions required for life to emerge [source].
For now, the dual-planet system remains a focal point for exoplanet research, offering a rare opportunity to study both a potentially habitable world and an extreme lava planet in the same stellar system. As technology advances, future missions may provide clearer answers about TOI-1752 c’s ability to support life—or at least, the conditions that could make it so.
