GJ 1002 b is a recently discovered Earth-mass planet located just 15.8 light-years away in the constellation Cetus. It is part of a two-planet system orbiting a very quiet red dwarf star.

Key Physical Characteristics

• Planet Type: Terrestrial (rocky) world.
• Mass: It is remarkably similar to Earth, with a minimum mass of about 1.08 times that of our planet.
• Orbit: It orbits its star, GJ 1002, very closely, completing a full “year” in just 10.3 Earth days.
• The Star: GJ 1002 is a “faint” red dwarf. Because the star is so cool and small, the habitable zone is much closer to it than in our solar system.

Habitability & Environment

In Lisa Kaltenegger’s 2026 catalog, GJ 1002 b is highlighted as a “prime real estate” candidate for life:

• Location: It sits comfortably in the inner part of the habitable zone.
• Energy Intake: It receives a level of stellar radiation similar to what Earth gets from the Sun. This means if it has an atmosphere, surface temperatures could allow for liquid water.
• Quiet Star Advantage: Like GJ 1061, this star is not very active. It doesn’t bombard its planets with the frequent, violent flares seen in the Proxima Centauri system, giving any potential atmosphere a much better chance of surviving over billions of years. 

Scientific Significance

• Double Opportunity: GJ 1002 b has a “twin” in the same system, GJ 1002 c, which also orbits in the habitable zone (further out, with a 21-day orbit). This makes the system a high-priority laboratory for comparing how two similar planets evolve.
• Detection Method: It was discovered using the radial velocity method (detecting the “wobble” of the star) by high-precision instruments like ESPRESSO and CARMENES.
• Future Observation: Because it is so close to Earth, it is one of the few planets where we might be able to characterize the chemical composition of its atmosphere using the next generation of Extremely Large Telescopes (ELTs) currently under construction.

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Published @ March 24, 2026 9:12 am