GJ 1061 d is the outer sibling of GJ 1061 c, located in the same star system just 12 light-years away. While planet “c” sits at the hot inner edge of the habitable zone, planet “d” is situated much more comfortably within it.

Key Physical Characteristics

• Planet Type: Terrestrial (rocky) Super-Earth.
• Mass: It is approximately 1.64 times the mass of Earth.
• Orbit: It takes about 13 Earth days to complete one orbit around its red dwarf star.
• Energy Intake: It receives only about 60% of the starlight that Earth gets from the Sun. This makes it a “colder” version of Earth, similar to the solar energy levels received by Mars.

Habitability & Environment

In Lisa Kaltenegger’s research, GJ 1061 d is often considered a “safer” bet for life than its inner neighbor because of its position:

• Temperature: Without an atmosphere, it would be a frozen world. However, with a thick greenhouse atmosphere (like CO2), it could maintain liquid water on its surface.
• The “Quiet” Star: Because the host star (Gliese 1061) is an older, quieter red dwarf, planet “d” has a high chance of having kept its atmosphere over billions of years, protected from the violent solar flares that plague planets like Proxima b.
• Liquid Water Potential: Its distance from the star suggests it could be a “cold habitable” world, potentially covered in ice with open oceans near the equator or under a thick insulating atmosphere.

Scientific Importance

GJ 1061 d is a high-priority target for the James Webb Space Telescope (JWST) because:

• Atmospheric Testing: It allows scientists to compare two planets in the same system (c and d) to see how distance from the star affects the evolution of an atmosphere.
• Life Search: It is one of the few nearby planets where we can realistically search for oxygen, methane, or water vapor in the coming years.

---

Published @ March 24, 2026 9:07 am