Kepler-441 b
Kepler-441 b is a confirmed “Super-Earth” located approximately 926 light-years away in the constellation Lyra. It orbits a red dwarf star that is significantly smaller and cooler than our Sun.
Key Physical Characteristics
- Planet Type: Terrestrial (rocky) Super-Earth.
- Size: It is about 1.6 times the radius of Earth.
- Orbit: It completes one orbit around its star every 137 Earth days.
- The Star: Kepler-441 is a K-type or late M-type star. Because it is dimmer than the Sun, the planet’s 137-day orbit puts it in a temperate zone similar to Earth’s 365-day orbit.
Habitability & Environment
In Lisa Kaltenegger’s research, Kepler-441 b is used to test the “outer limits” of the habitable zone:
- Location: It sits near the outer edge of its star’s habitable zone.
- Energy Intake: It receives about 20% to 25% of the starlight that Earth gets from the Sun. This makes it a very cold world, likely similar to a “warm” version of Mars.
- Atmosphere: Because the planet is 1.6 times larger than Earth, it has the gravity required to hold onto a very thick atmosphere. If this atmosphere is rich in greenhouse gases like carbon dioxide, it could trap enough heat to allow for liquid water on the surface despite the low starlight.
Scientific Significance
- The Radius Limit: At 1.6 times Earth’s radius, Kepler-441 b is at the absolute limit of what scientists consider a “rocky” world. Any larger, and it would likely be a “Mini-Neptune” made mostly of gas.
- Atmospheric Resilience: Because it orbits further away from its star than many other red dwarf planets, it is safer from the violent solar flares that often strip atmospheres away from closer worlds.
- Discovery: It was discovered by the Kepler Space Telescope using the transit method. Its large size and clear orbital signal made it a highly reliable candidate for the 2026 top-45 list.
Published @ March 24, 2026 9:39 am