Ross 128

system

Ross 128 is a quiet red dwarf 11 light-years away in Virgo, unusually inactive for its type. It hosts one confirmed planet, Ross 128 b — the second-closest known temperate exoplanet after Proxima b.

Open in 3D viewSee Ross 128 in the live, interactive 3D map

Key facts

Type

Red dwarf + 1 planet

Distance

11.01 light-years

Confirmed planets

Science

Classification

Type: Single red-dwarf system
Central star: Ross 128 — M4V red dwarf (~3190 K, ~0.17 M☉)

Planets

Confirmed planets: 1 · Ross 128 b — temperate (equilibrium ~300 K)
Mass: Radial-velocity minimum mass ~1.4 Earth

Distance & nature

Distance: 11.01 light-years
Star activity: Quiet · flares far less than Proxima Centauri

How we know

Note: Ross 128 b is confirmed but was found by radial velocity, so its mass is a MINIMUM mass and its radius is a model estimate — it has not transited or been imaged, and whether it holds water or air is unknown. The map position is symbolic; the real distance is 11.01 light-years.

Discovery & history

Name: Named for the astronomer Frank Elmore Ross and its catalogue number.

Catalogued by Frank Elmore Ross in 1926; its temperate planet was found by ESO's HARPS in 2017.

Images

Where to find it — in Virgo, the Maiden (IAU constellation chart). It is an unresolved point of light; its surface has never been imaged. — IAU / Sky & Telescope, R. Sinnott & R. Fienberg (CC BY 3.0) · Wikimedia Commons

Images from open archives · credit shown per image