Astronomers Confirm GJ 887 d 10.7 Light-Years Away as Second-Closest Habitable-Zone Planet
Updated
Updated · spacedaily.com · Jul 26
Astronomers Confirm GJ 887 d 10.7 Light-Years Away as Second-Closest Habitable-Zone Planet
1 articles · Updated · spacedaily.com · Jul 26
Summary
GJ 887 d has been confirmed after six years of doubt, making it the second-closest known habitable-zone planet after Proxima Centauri b and placing it 10.7 light-years from Earth.
101 new HARPS measurements, 12 from ESPRESSO and a denser observing cadence let the RedDots team separate the planet’s 50.77-day signal from the red dwarf’s roughly 38.7-day rotation, yielding about a 4.6-sigma detection.
The planet orbits at 0.212 AU and receives about 81% of Earth’s sunlight, but astronomers stress that habitable-zone status does not show it is habitable, inhabited or even rocky.
Radial-velocity data give only a minimum mass of about 6 Earth masses, leaving GJ 887 d potentially a super-Earth, water-rich world or small Neptune with no measured radius or atmosphere.
Its proximity makes the system a prime follow-up target for future direct-imaging missions, even though the planet does not transit and remains difficult for current atmospheric studies.