GJ 1214 b
ILLUSTRATION FROM EQUILIBRIUM TEMPERATURE 567 K · RADIUS 2.73 EARTH RADII · HOST STAR 3100 K
OVERVIEW
] EXOPLANETGJ 1214 b is a Neptune-like planet in the constellation Ophiuchus, 47.76 from Earth. It orbits GJ 1214 at a mean distance of 0.01505 . It has a mass of 8.41 and a radius of 2.73 · 17 431 . It was discovered in 2009.
The archetypal sub-Neptune: a class of planet with no Solar System counterpart, wrapped in a haze thick enough to have defeated a decade of attempts to see through it.
- WHAT IT IS
- Neptune-like planet
- HOW FAR
- 47.76
- HOW BIG
- 2.73 · 17 431
- ONE ORBIT TAKES
- 37.9
The light arriving now left it that long ago.
Its radius: half the width across.
One trip round GJ 1214.
THE MODEL
] CATALOGUED RADIUSCALCULATED · NOT AN OBSERVATION · CATALOGUED RADIUS · EQUILIBRIUM TEMPERATURE 567 K · RADIUS 2.73 EARTH RADII · HOST STAR 3100 K
Drawn from the catalogued radius and from the same properties the picture at the top of this page uses, at the distance a flight to it would stop. Drag it, or use the arrow keys, to look from another direction. The stars behind are the 498,631 this catalogue holds real distances for, at their real positions and drawn from where the camera actually is — so the constellations are wrong, and that is the point. This is the sky from there, not the sky from here.
OBSERVING
] FROM WHERE YOU AREWhat it takes to see GJ 1214 b for yourself. Everything in this part of the page is worked out for a real horizon, a real night and the equipment you say you have.
Say where you are, and this line says when GJ 1214 b is worth going out for.
APPARENT PLACE
] EQUINOX J2026.7Where a telescope has to be pointed today, which is not quite where the catalogue records the object: the coordinate grid itself has turned since the year 2000 the catalogue is referred to.
- RIGHT ASCENSION
- DECLINATION
- GRID TURNED SINCE
- 19.9
- PROPER MOTION SINCE
- none published
Computed for 2026-08-27 00:00 UT. No proper motion is published for GJ 1214 b, so nothing here moves the object; what separates this from the catalogued position above is the coordinate grid turning under it — about fifty arcseconds a year of precession since 2000, and the small nodding of the Earth’s axis on top of that. Aberration and refraction are not included, and neither is parallax; each is under an arcminute, which is also about as well as the catalogued position is known. The same figure for any date.
CATALOG DATA
] 17 FIELDSThe raw catalogue values, as the source published them, with the error bars where one was published — sorted by what each set of figures is about rather than by the order they happened to be stored in.
WHAT IT IS MADE OF
What the object is in itself, rather than how it happens to look from here.
- Equilibrium temperature
- 567
- Host star spectral type
- Host star temperature
- 3101 ±43
- Host star mass
- 0.182 +0.0042 / −0.0041
- Host star radius
- 0.2162 +0.0025 / −0.0024
HOW BRIGHT IT IS
What the light adds up to, measured through one filter at a time. A magnitude is a brightness on a backwards scale — the smaller the number, the brighter the object.
- Host star apparent magnitude ()
THE ORBIT
The shape of the path, where the object sits on it, and the instant those figures were true of. An orbit is a fit to observations and drifts away from the real one either side of its epoch.
- Host star
- GJ 1214
- Orbital period
- 1.5804 +1.8×10⁻⁸ / −1.7×10⁻⁸
- Eccentricity
- +0.0079 / −0.0044
- Inclination
- 88.98 +0.094 / −0.085
- Argument of periastron
- 77 +7.5 / −61
- Periastron epoch
- 2459639.7250
- Transit midpoint
- 2459639.7813
- Stars in system
- 1
- Planets in system
- 1
WHEN IT WAS FOUND
Who first saw it, from where, and by what method.
- Discovery method
- Transit
- Discovered at
- MEarth Project
ALSO KNOWN AS
] 2 DESIGNATIONS- Exoplanet GJ 1214 b
- Host star GJ 1214
LOOK IT UP ELSEWHERE
] 4 SERVICESEach link carries the identifier printed beside it. Nothing on this page is a measurement of our own, so a number that disagrees with one of these is worth reporting — and a service that has never catalogued this object under this name will say so plainly.
- NASA Exoplanet ArchiveGJ 1214 b
Every published parameter set for this planet side by side, with the paper each one came from.
- SIMBADGJ 1214
Cross-identifications, measured values and the reference behind each of them. Keyed on the host star.
- ADSobject:"GJ 1214"
Papers indexed against this object rather than against the string, newest first. Keyed on the host star.
- VizieR5″ around 258.8314 +4.9607
Every published table with a row at this position, searched by coordinates rather than by name.
CITE THIS PAGE
] DR1This page is live and its numbers move when an upstream refreshes, so the citation names the release the rows belong to rather than the day you read them. The release itself is frozen, republished as a bundle, and is what a data-availability statement should point at.
SpaceCatalog. GJ 1214 b [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/gj-1214-b
@misc{spacecatalog_gj-1214-b,
author = {{SpaceCatalog}},
title = {{GJ 1214 b}},
howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
year = {2026},
url = {https://spacecatalog.org/object/gj-1214-b},
note = {Catalogue entry, data release DR1 (2026-08-21). Values from NASA Exoplanet Archive (Planetary Systems Composite Parameters).}
}The values above were taken from NASA Exoplanet Archive (Planetary Systems Composite Parameters) — Public domain (NASA). Citing this page does not replace citing that catalogue.
RECENT ACTIVITY
] 3 ITEMS- Impact of Clouds on the Atmosphere-Mantle Interface of Sub-Neptunes2026-05-26 · arXiv · PAPER · Sagnick Mukherjee, Matthew C. Nixon, Luis Welbanks, James Mang, Nicholas F. Wogan, Natasha E. Batalha
- Cloudy with a chance of metals: Indications of CO$_2$ in the atmosphere of GJ 1214 b from high-resolution K-band spectroscopy2026-04-16 · arXiv · PAPER · L. Nortmann, D. Cont, F. Lesjak, A. D. Rains, A. Lavail, L. Boldt-Christmas
- Atmospheric constraints on GJ 1214 b from CRIRES+ and prospects for characterisation with ANDES2026-02-15 · arXiv · PAPER · A. Peláez-Torres, A. Sánchez-López, C. Jiang, E. Pallé, J. Orell-Miquel, M. López-Puertas
arXiv · UPDATED DAILY