UPSA Object Registry
Registry · exoplanet

GJ 581 b

Exoplanet
harvesting The full record is being pulled from the archives right now — measurement tables, the Gaia row, catalogue photometry. This page will fill itself in.
Right ascension
15h 19m 25.55s
Declination
−07° 43′ 21.7″
Galactic l, b
354.07, 40.02
Magnitude V
10.57
Distance
6.2981 pc

Planet

NASA Exoplanet Archive, composite parameters
Host starGJ 581 · M3.0 V
DiscoveryRadial Velocity, 2005 · La Silla Observatory
Orbital period5.3686 d
Semi-major axis0.0399 au
Eccentricity0.0342
Radius4.79 R⊕ · 0.427 R♃
Mass20.5 M⊕ · 0.0645 M♃
Density1.02 g/cm³
Equilibrium temperature464.32 K
System distance6.2981 pc

Published measurements

4 quantities measured more than once
One object can carry a dozen published estimates of the same quantity. The register keeps them side by side rather than picking a winner — the citation is part of the value.

Mass 7 values

ValueUnitUncertainty Band / methodSourceReferenceYear
20.5 M_earth ± 6.2 Radial Velocity NASA Exoplanet Archive von Stauffenberg et al. 2024 2024
16.24103 M_earth ± 0.6039 Radial Velocity NASA Exoplanet Archive Rosenthal et al. 2021 2021
15.2 M_earth ± 0.22 Radial Velocity NASA Exoplanet Archive Trifonov et al. 2018 2018
15.8 M_earth ± 0.3 Radial Velocity NASA Exoplanet Archive Robertson et al. 2014 2014
15.6 M_earth ± 0.3 Radial Velocity NASA Exoplanet Archive Vogt et al. 2010 2010
15.65 M_earth Radial Velocity NASA Exoplanet Archive Mayor et al. 2009 2009
16.6 M_earth Radial Velocity NASA Exoplanet Archive Bonfils et al. 2005 2005

Orbital period 7 values

ValueUnitUncertainty Band / methodSourceReferenceYear
5.3686 d ± 0.0001 Radial Velocity NASA Exoplanet Archive von Stauffenberg et al. 2024 2024
5.36879 d ± 0.00015 Radial Velocity NASA Exoplanet Archive Rosenthal et al. 2021 2021
5.368 d ± 0.001 Radial Velocity NASA Exoplanet Archive Trifonov et al. 2018 2018
5.3686 d ± 0.0001 Radial Velocity NASA Exoplanet Archive Robertson et al. 2014 2014
5.36841 d ± 0.00026 Radial Velocity NASA Exoplanet Archive Vogt et al. 2010 2010
5.36874 d ± 0.00019 Radial Velocity NASA Exoplanet Archive Mayor et al. 2009 2009
5.366 d ± 0.001 Radial Velocity NASA Exoplanet Archive Bonfils et al. 2005 2005

Semi-major axis 7 values

ValueUnitUncertainty Band / methodSourceReferenceYear
0.0399 au ± 0.0005 Radial Velocity NASA Exoplanet Archive von Stauffenberg et al. 2024 2024
0.04099 au ± 0.00042 Radial Velocity NASA Exoplanet Archive Rosenthal et al. 2021 2021
0.041 au ± 0.001 Radial Velocity NASA Exoplanet Archive Trifonov et al. 2018 2018
0.04061 au ± 3.00e-05 Radial Velocity NASA Exoplanet Archive Robertson et al. 2014 2014
0.0406163 au ± 1.30e-06 Radial Velocity NASA Exoplanet Archive Vogt et al. 2010 2010
0.04 au Radial Velocity NASA Exoplanet Archive Mayor et al. 2009 2009
0.041 au Radial Velocity NASA Exoplanet Archive Bonfils et al. 2005 2005

Eccentricity 7 values

ValueUnitUncertainty Band / methodSourceReferenceYear
0.0342 ± 0.009 Radial Velocity NASA Exoplanet Archive von Stauffenberg et al. 2024 2024
0.02 ± 0.022 Radial Velocity NASA Exoplanet Archive Rosenthal et al. 2021 2021
0.022 ± 0.027 Radial Velocity NASA Exoplanet Archive Trifonov et al. 2018 2018
0 ± 0.03 Radial Velocity NASA Exoplanet Archive Robertson et al. 2014 2014
0 Radial Velocity NASA Exoplanet Archive Vogt et al. 2010 2010
0 Radial Velocity NASA Exoplanet Archive Mayor et al. 2009 2009
0 Radial Velocity NASA Exoplanet Archive Bonfils et al. 2005 2005

In the same field

within 9 arcmin · wider search
ObjectTypeSeparationV
GJ 581 e Exoplanet 0″ 10.57
GJ 581 Star 0″ —
GJ 581 c Exoplanet 0″ 10.57
BD-07 4003d Planet 18.99″ —
BD-07 4003e Planet 18.99″ —
BD-07 4003g Planet Candidate 18.99″ —
BD-07 4003f Planet Candidate 18.99″ —
BD-07 4003 BYDraV* 18.99″ 10.56
BD-07 4003b Planet 18.99″ —
BD-07 4003c Planet 18.99″ —
LP 682-27 HighPM* 349.5″ 13.24

Provenance

where this card came from
ArchiveRead at (UTC)Record
Seeded from the bulk archive load; no per-object fetch yet.

Machine-readable: /api/v1/object/gj-581-b · Registry entry updated 2026-08-14.