Gliese 436

Gliese 436

system

Gliese 436 is a red dwarf 31.9 light-years away in Leo, host to one of the best-studied warm Neptunes known. Its single planet transits, so its size and density are measured directly, and it moves on an oddly tilted, eccentric orbit while shedding an enormous cloud of hydrogen that streams behind it like a comet's tail.

Open in 3D viewSee Gliese 436 in the live, interactive 3D map

Key facts

Type
Red dwarf + 1 planet
Distance
31.9 light-years
Confirmed planets
1
Planet
Transiting warm Neptune

Science

Classification

Type
Single red-dwarf system
Central star
Gliese 436 — M2.5V red dwarf (~3586 K, 0.47 M☉)

Planets

Confirmed planets
1 · Gliese 436 b, a transiting warm Neptune
Measured
Real size + density (it transits)

Distance

Distance
31.9 light-years · in Leo

How we know

Note
One confirmed planet (NASA Exoplanet Archive, checked 2026-07-05). Because it transits, its radius and density are genuinely measured — unusual for a nearby planet. Map distance is symbolic; the real gap is 31.9 light-years.

Discovery & history

Name
A catalogue designation (Gliese 436); the star has no proper name.

Its planet was found by radial velocity in 2004 and caught transiting in 2007 — the first confirmed Neptune-sized transiting world.

Images

Where to find it — in Leo, the Lion (IAU constellation chart). To the eye it is a single point of light; no telescope has imaged its surface.
IAU / Sky & Telescope, R. Sinnott & R. Fienberg (CC BY 3.0) · Wikimedia Commons

Images from open archives · credit shown per image