Kepler-1649 c

Kepler-1649 c is often called one of the most “Earth-like” planets ever found in terms of size and temperature. It is located approximately 300 light-years away in the constellation Cygnus.

Key Physical Characteristics

Planet Type: Terrestrial (rocky) world.
Size: It is almost a perfect twin to Earth, with a radius about 1.06 times that of our planet.
Orbit: It orbits its small red dwarf star very closely, completing a full “year” in just 19.5 Earth days.
The Star: Kepler-1649 is a low-mass red dwarf. Because the star is much cooler than our Sun, its habitable zone is located much closer to the stellar surface.

Habitability & Environment

In Lisa Kaltenegger’s research, Kepler-1649 c is a “top-tier” candidate for an Earth-like climate:

Energy Intake: It receives about 75% of the starlight that Earth gets from the Sun. This puts it in a temperature range very similar to Earth’s—somewhere between the climate of Earth and Mars.
Temperature: If it has an atmosphere similar to ours, its equilibrium temperature could allow for liquid water to exist on the surface.
Tidal Locking: Like most planets orbiting red dwarfs, it is likely tidally locked. However, because its size is so close to Earth’s, it is a primary subject for climate models to see if its atmosphere can distribute heat effectively.

Scientific Significance

The “Hidden” Discovery: This planet was originally missed by computer algorithms and was only discovered years later when scientists re-analyzed the Kepler Space Telescope’s observations by hand.
System Resonance: It has an inner sibling (planet “b”) which is too hot for life. The two planets orbit in a stable pattern, which is a good sign for long-term climate consistency.
Earth-Size Benchmark: Because it is not a “Super-Earth” but almost exactly Earth-sized, it is one of the most important benchmarks for understanding how rocky planets form and maintain habitability around red dwarfs.

Published @ March 24, 2026 9:34 am