Key parameters at a glance

A radius of 1.19 Earth radii
A mass of 1.84 Earth masses
Surface gravity around 1.29 g
An orbital period of 1.629 days
Semi-major axis 0.0157 AU
Equilibrium temperature 584 K (311 °C)
Distance from Earth 41.14 light-years
Earth Similarity Index 0.537
Travel time at Voyager 1 speed 725,470 years
Almost certainly tidally locked to its host star given the close orbit

Context from the literature

GJ 1132 b is an exoplanet orbiting GJ 1132, a red dwarf star 41 light-years from Earth, in the constellation Vela. The planet is considered uninhabitable but was thought to be cool enough to possess an atmosphere. GJ 1132 b was discovered by the MEarth-South array in Chile.

Excerpted from Wikipedia · full article

1 sibling around GJ 1132

GJ 1132 b shares its host star with 1 other confirmed planet. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
GJ 1132 b this	Rocky Terrestrial	1.19	1.84	1.629	584	2015
GJ 1132 c	Super-Earth	1.43	2.64	8.929	300	2018

GJ 1132 b Planet Profile

Physical Specs

Radius

1.19 R⊕

Radius (Jupiter)

0.106 R♃

Mass

1.84 M⊕

Mass (Jupiter)

0.006 M♃

Density

5.97 g/cm³

Surface Gravity

1.29 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.537

HZ Position Inner

Controversial No

Discovery

Year 2015

Method Transit

Facility Cerro Tololo Inter-American Observatory

Telescope MEarth-South telescope array

Size rank in cohort

Rank by radius

#99of 570

top 17.2%

This planet

1.19R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

K2-384 c 1.19 R⊕ GJ 1252 b 1.19 R⊕ Kepler-953 c 1.19 R⊕

Metric	Earth	GJ 1132 b	Jupiter
Radius (R⊕)	1.00	1.19	11.21
Mass (M⊕)	1.00	1.84	317.83
Density (g/cm³)	5.51	5.97	1.33
Surface Gravity (g)	1.00	1.29	2.53
Insolation (S⊕)	1.00	19.30	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	1.837 M⊕	Direct mass measurement (not derived).
Minimum mass (M sin i)	1.837 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

TIC

TIC 101955023

Gaia DR2

Gaia DR2 5413438219396893568

Gaia DR3

Gaia DR3 5413438219396893568

System

GJ 1132

Percentile among Rocky Terrestrial cohort

Radius 1.192 R⊕ · percentile 83 / cohort 570

Mass 1.837 M⊕ · percentile 76 / cohort 570

Orbital period 1.63 d · percentile 18 / cohort 567

Distance 12.61 pc · percentile 7 / cohort 566

ESI 0.537 · percentile 73 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

1.629 days

Semi-major axis

0.0157 AU

Eccentricity

0.012

Inclination

88.16 °

Year Length

A year here lasts approximately 1.63 Earth days (0.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0157 AU.

Transit Fingerprint

Depth

0.244 %

Duration

0.766 h

Impact parameter b

0.504

Rp / R★

0.049430

Transit midpoint (BJD)

2,459,280.9899

Photometric dip

Transit produces a flux drop of 2,443 ppm lasting ≈ 0.77 h.

Extended Orbital Architecture

Planet / star radius ratio

0.049430

Semi-major axis / stellar radius

15.260

Impact parameter (b)

0.504

RV semi-amplitude (K)

2.980 m/s

Transit mid-time (BJD)

2,459,280.9899

Long. of periastron (ω)

-95.80°

Angular separation (arcsec)

1.24000

Eq. Temperature

584K

(311 °C)

Insolation (S⊕)

19.30

Earth = 1.00

Earth Similarity (ESI)

0.537

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Discovery Paper

Primary reference

Berta Thompson et al. 2015

Instrument

Apogee CCD Sensor

Publication

2015-11

Observation locale

Ground

Host System: GJ 1132

Spectral Class

M-type red dwarf

Effective Temperature

3,229 K — cooler than the Sun (5,778 K)

Estimated Age

5.00 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.221 R☉

Stellar Mass

0.195 M☉

Metallicity [Fe/H]

-0.17

Extended Stellar Properties

Surface gravity (log g)

5.037 dex

Stellar density

25.300 g/cm³

Systemic radial velocity

35.08 km/s

Rotational v·sin i

2.00 km/s

Rotation period

122.30 days

Metallicity ratio

[Fe/H]

Distance

12.61 parsec

Light-years 41.14 ly

V-band magnitude

13.68 mag

Voyager-speed travel 725,470 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

79.254 mas

Total Proper Motion

1,132.483 mas/yr

PM Right Ascension

-1,053.98 mas/yr

PM Declination

414.30 mas/yr

Galactic Cartesian (pc)

x = -0.610 · y = 0.301 · z = -0.733

Equatorial (J2000)

RA 153.70907° · Dec -47.15494°

Galactic ℓ, b

277.255° · 7.759°

Ecliptic λ, β

181.434° · -52.420°

HTM-20 index

-2025276557

Observation Record

Transmission spectra

Emission spectra

Archive notes

Wikipedia → Image: Wikimedia Commons · Aldaron, a.k.a. Aldaron · CC BY-SA 3.0