Record-holder
GJ 1132
A Venus analog 41 ly away — terrestrial world losing its atmosphere.
- Planets
- 2
- Distance
- 41.1 ly
- Host
- M-type
About GJ 1132
Discovery
GJ 1132 b was discovered in 2015 by the MEarth-South project (Berta-Thompson et al., Nature) — a rocky 1.2 R⊕ planet transiting a nearby M4.5 dwarf 41 light-years away, often described as a Venus analog.
Why it matters
GJ 1132 b is one of the closest rocky planets transiting an M-dwarf, making it a key laboratory for whether terrestrial worlds around red dwarfs can hold on to atmospheres against intense XUV radiation.
Current research
Early Hubble work suggested a thin atmosphere, but recent JWST transmission spectra (Xue et al. 2024) returned a featureless spectrum — consistent with a bare rock or only a tenuous atmosphere.
Comparable to
A scorched Venus-cousin slightly larger than Earth — close enough to study, hot enough that any atmosphere is fighting for survival.
System geometry
At a glance
- Hostname
- GJ 1132
- Spectral type
- M4.5 V
- Distance
- 41.1 ly · 12.61 pc
- Stellar mass
- 0.20 M☉
- Stellar radius
- 0.23 R☉
- Luminosity
- 4.77e-3 L☉
- Effective temp
- 3090 K
- Confirmed planets
- 2
- Habitable zone
- 0.066 – 0.095 AU
Top-down orbital diagram
Orbits to scale within this system. Dashed green = habitable-zone edges.
Planet positions are illustrative (evenly spaced in phase). For live motion see the 3D scene.
The planets
2 confirmed.
Rocky world
GJ 1132 b
- Orbit
- 0.016 AU
- Period
- 1.63 days
- Radius
- 1.22 R⊕
- Mass
- 1.69 M⊕
- Eq. temperature
- 591 K
- Eccentricity
- 0.000
- Discovered
- 2015 · Transit
Rocky world
GJ 1132 c
- Orbit
- 0.048 AU
- Period
- 8.93 days
- Radius
- 1.43 R⊕
- Mass
- 2.64 M⊕
- Eq. temperature
- 300 K
- Eccentricity
- 0.270
- Discovered
- 2018 · Radial Velocity
Compared to our Solar System
Each row shows the closest Solar-System analog by radius (log-space). Earth is pinned at the bottom as the constant frame of reference.
| Planet | Radius (R⊕) | Mass (M⊕) | Orbit (AU) | Period (days) | Eq temp (K) | Solar analog |
|---|---|---|---|---|---|---|
| GJ 1132 b | 1.22 | 1.69 | 0.016 | 1.63 | 591 | Earth |
| GJ 1132 c | 1.43 | 2.64 | 0.048 | 8.93 | 300 | Earth |
| Earth (reference) | 1.00 | 1.00 | 1.000 | 365.25 | 255 | — |
Research status
◇ JWST observation status
1 planet has confirmed JWST observation time across Cycles 1–3.
- GJ 1132 b
JWST programs include transit spectroscopy, thermal phase curves, and direct imaging coronagraph observations depending on planet class.
Discovery timeline
- 2015
GJ 1132 b
via Transit
- 2018
GJ 1132 c
via Radial Velocity
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Experience it
See GJ 1132 in interactive 3D
Fly through the system, click any planet, watch orbits play out at 100× speed.
▶ Launch 3D scene