UPSA Object Registry
Registry · exoplanet

Kepler-18 b

Exoplanet 84 papers
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
19h 52m 19.07s
Declination
+44° 44′ 46.5″
Galactic l, b
79.007, 8.92
Magnitude V
13.77
Distance
433.05 pc

Also known as

1 identifiers

Kepler-18b

Planet

NASA Exoplanet Archive, composite parameters
Host starKepler-18
DiscoveryTransit, 2011 · Kepler
Orbital period3.50473 d
Semi-major axis0.0447 au
Eccentricity0
Radius2 R⊕ · 0.178 R♃
Mass6.9 M⊕ · 0.022 M♃
Density4.9 g/cm³
Equilibrium temperature1,165 K
System distance433.05 pc

Published measurements

6 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 4 values

ValueUnitUncertainty Band / methodSourceReferenceYear
140.397 M_earth Transit NASA Exoplanet Archive Ofir et al. 2025 2025
30.4165 M_earth Transit NASA Exoplanet Archive Ofir et al. 2025 2025
12.7511 M_earth ± 3.906 Transit NASA Exoplanet Archive Weiss et al. 2024 2024
6.9 M_earth ± 3.4 Transit NASA Exoplanet Archive Cochran et al. 2011 2011

Radius 10 values

ValueUnitUncertainty Band / methodSourceReferenceYear
1.809 R_earth ± 0.208 Transit NASA Exoplanet Archive Weiss et al. 2024 2024
1.778 R_earth ± 0.186 Transit NASA Exoplanet Archive Berger et al. 2018 2018
1.809 R_earth ± 0.208 Transit NASA Exoplanet Archive Fulton & Petigura 2018 2018
2.09 R_earth ± 0.31 Transit NASA Exoplanet Archive Morton et al. 2016 2016
2.11 R_earth ± 0.14 Transit NASA Exoplanet Archive Q1-Q16 KOI Table 2011
2.11 R_earth ± 0.14 Transit NASA Exoplanet Archive Q1-Q12 KOI Table 2011
2 R_earth ± 0.1 Transit NASA Exoplanet Archive Cochran et al. 2011 2011
2.03 R_earth ± 0.13 Transit NASA Exoplanet Archive Q1-Q17 DR25 KOI Table 2011
1.82 R_earth ± 0.17 Transit NASA Exoplanet Archive Q1-Q8 KOI Table 2011
2.11 R_earth ± 0.14 Transit NASA Exoplanet Archive Q1-Q17 DR24 KOI Table 2011

Orbital period 13 values

ValueUnitUncertainty Band / methodSourceReferenceYear
3.504691 d ± 3.10e-06 Transit NASA Exoplanet Archive Ofir et al. 2025 2025
3.504688 d Transit NASA Exoplanet Archive Weiss et al. 2024 2024
3.504727 d ± 3.78e-06 Transit NASA Exoplanet Archive Gajdoš et al. 2019 2019
3.504688 d ± 3.58e-06 Transit NASA Exoplanet Archive Fulton & Petigura 2018 2018
3.504688 d ± 3.58e-06 Transit NASA Exoplanet Archive Morton et al. 2016 2016
3.504713 d ± 1.39e-06 Transit NASA Exoplanet Archive Holczer et al. 2016 2016
3.504691 d ± 3.09e-06 Transit NASA Exoplanet Archive Q1-Q17 DR25 Supplemental KOI Table 2011
3.504688 d ± 3.58e-06 Transit NASA Exoplanet Archive Q1-Q16 KOI Table 2011
3.504688 d ± 3.58e-06 Transit NASA Exoplanet Archive Q1-Q12 KOI Table 2011
3.504725 d ± 2.80e-05 Transit NASA Exoplanet Archive Cochran et al. 2011 2011
3.504691 d ± 3.09e-06 Transit NASA Exoplanet Archive Q1-Q17 DR25 KOI Table 2011
3.504761 d ± 1.70e-05 Transit NASA Exoplanet Archive Q1-Q8 KOI Table 2011
Show the remaining 1
ValueUnitUncertainty Band / methodSourceReferenceYear
3.504688 d ± 3.58e-06 Transit NASA Exoplanet Archive Q1-Q17 DR24 KOI Table 2011

Semi-major axis 8 values

ValueUnitUncertainty Band / methodSourceReferenceYear
0.04489768 au Transit NASA Exoplanet Archive Weiss et al. 2024 2024
0.04492 au ± 0.00039 Transit NASA Exoplanet Archive Fulton & Petigura 2018 2018
0.0434 au Transit NASA Exoplanet Archive Q1-Q16 KOI Table 2011
0.0434 au Transit NASA Exoplanet Archive Q1-Q12 KOI Table 2011
0.0447 au ± 0.0006 Transit NASA Exoplanet Archive Cochran et al. 2011 2011
0.0434 au Transit NASA Exoplanet Archive Q1-Q17 DR25 KOI Table 2011
0.044 au Transit NASA Exoplanet Archive Q1-Q8 KOI Table 2011
0.0434 au Transit NASA Exoplanet Archive Q1-Q17 DR24 KOI Table 2011

Eccentricity 7 values

ValueUnitUncertainty Band / methodSourceReferenceYear
0 Transit NASA Exoplanet Archive Weiss et al. 2024 2024
0 Transit NASA Exoplanet Archive Q1-Q16 KOI Table 2011
0 Transit NASA Exoplanet Archive Q1-Q12 KOI Table 2011
0 Transit NASA Exoplanet Archive Cochran et al. 2011 2011
0 Transit NASA Exoplanet Archive Q1-Q17 DR25 KOI Table 2011
0 Transit NASA Exoplanet Archive Q1-Q8 KOI Table 2011
0 Transit NASA Exoplanet Archive Q1-Q17 DR24 KOI Table 2011

Equilibrium temperature 5 values

ValueUnitUncertainty Band / methodSourceReferenceYear
1,165 K Transit NASA Exoplanet Archive Q1-Q16 KOI Table 2011
1,165 K Transit NASA Exoplanet Archive Q1-Q12 KOI Table 2011
1,165 K Transit NASA Exoplanet Archive Q1-Q17 DR25 KOI Table 2011
1,120 K Transit NASA Exoplanet Archive Q1-Q8 KOI Table 2011
1,165 K Transit NASA Exoplanet Archive Q1-Q17 DR24 KOI Table 2011

In the same field

within 9 arcmin · wider search
ObjectTypeSeparationV
Kepler-18 c Exoplanet 0.003074″ 13.77
Kepler-18 d Exoplanet 0.003074″ 13.77
Kepler-18 Eruptive* 0.3159″ 13.77
KOI-3384.01 Planet Candidate 52.52″ —
Kepler-1485 Star 52.52″ —
Kepler-1485 b Exoplanet 52.6″ 13.41
KOI-5552.01 Planet Candidate 151.4″ —
KOI-5552 ** 151.4″ 13.61
2MASS J19522062+4447386 Star 173″ —
2MASS J19520975+4447101 Star 174.7″ —
2MASS J19523597+4444521 Star 180.2″ —

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/kepler-18-b · Registry entry updated 2026-08-14.