Kepler-452 b is famously known as “Earth’s Older Cousin.” Located approximately 1,400 light-years away in the constellation Cygnus, it was the first Earth-sized planet found orbiting a star very similar to our own Sun.

Key Physical Characteristics

• Planet Type: Terrestrial (rocky) Super-Earth.
• Size: It is about 1.6 times the radius of Earth.
• Orbit: Its “year” is very familiar, completing one orbit in 385 Earth days.
• The Star: Kepler-452 is a G-type star, the same class as our Sun. It has almost the same temperature, though it is about 1.5 billion years older than our Sun.

Habitability & Environment

In Lisa Kaltenegger’s research, Kepler-452 b provides a fascinating look at the potential future of a habitable world:

• Energy Intake: It receives about 10% more starlight than Earth gets. This puts it in a very similar climate category to our own planet.
• Temperature: If it has an atmosphere like Earth’s, its surface temperature would be around -8 °C. However, with a natural greenhouse effect, it would be comfortably warm enough for liquid water.
• An Aging World: Because its sun is older than ours, it has become slightly brighter and hotter over time. This means Kepler-452 b might be undergoing a gradual warming process, showing us what might happen to Earth in a billion years.

Scientific Significance

• Sun-Like System: While most planets on the “top 45” list orbit small red dwarfs, Kepler-452 b is rare because it orbits a Sun-like star. This means it does not face the extreme radiation flares or tidal locking issues common to red dwarf systems.
• High Gravity: Due to its mass, the surface gravity is likely twice as strong as Earth’s. You would feel much heavier, and the planet would have no trouble holding onto a very thick, protective atmosphere.
• Solid Surface: Its size suggests a high probability of having a rocky, solid surface with the potential for volcanic activity and oceans.

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Published @ March 24, 2026 9:44 am