Discovery Method
Radial Velocity
Consistent across records
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ExoplanetDetail
55 Cnc e
Host star 55 Cnc • 1.88 R⊕ • 0.74 d orbit
Records
21
archive rows
Discovery
2004
Radial Velocity
Radius
1.88 R⊕
default parameter set
Mass
7.99 M⊕
default parameter set
55 Cnc
temperature unconstrained
Canonical Summary
Adopted planet values from the default parameter set
Values come from the archive's default parameter set. Missing values stay missing. Ranges and counts describe all source rows.
Selected source: Bourrier et al. 2018
Host Star
55 Cnc
Stable across source rows
Discovery Year
2004
Stable across source rows
Orbital Period
0.74 day
0.74 to 2.81
Semi-Major Axis
0.02 au
0.01 to 0.04
Radius
1.88 Rearth
1.86 to 2.17
Mass
7.99 Mearth
7.47 to 14.30
Density
6.66 g/cm**3
4.50 to 6.66
Scale Comparison
Radius against familiar reference worlds
Current adopted radius: 1.88 R⊕ • circles scaled linearly by radius
Earth
1.0 R⊕ baseline
55 Cnc e
1.88 R⊕
Jupiter
11.2 R⊕ reference
Provenance
Underlying measurements and references
Evidence Summary
Rows
21
Refs
21
Methods
1
Discoverystable
Facilitystable
Perioddisputed
Radiusdisputed
Massdisputed
Eq. Tempdisputed
| Year | Method | Facility | Telescope | Period | Radius | Mass | Eq. Temp | Reference |
|---|---|---|---|---|---|---|---|---|
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 2 Rearth | 8.63 Mearth | — | Winn et al. 2011 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 2.08 Rearth | 7.81 Mearth | 1958 K | Demory et al. 2011 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | — | 1.92 Rearth | 8.08 Mearth | — | Demory et al. 2016 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 2.17 Rearth | 8.37 Mearth | — | Endl et al. 2012 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 2.80 day | — | 7.47 Mearth | — | Wright et al. 2009 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 2.81 day | — | 14.30 Mearth | — | McArthur et al. 2004 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | 8.09 Mearth | — | Nelson et al. 2014 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | 8.14 Mearth | — | Baluev 2015 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | — | — | Bourrier & Hébrard 2014 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 1.90 Rearth | 7.74 Mearth | — | Dai et al. 2019 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | — | — | — | — | Knapp et al. 2020 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 2.02 Rearth | — | 1831.3 K | ExoFOP |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 1.86 Rearth | — | — | Zhao et al. 2023 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | 9.35 Mearth | — | Moutou et al. 2026 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | 7.95 Mearth | — | Harada et al. 2025 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 1.91 Rearth | 8.08 Mearth | — | Demory et al. 2016 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 1.88 Rearth | 7.99 Mearth | — | Bourrier et al. 2018 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | 9.38 Mearth | — | Rosenthal et al. 2021 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | 1.95 Rearth | 8.59 Mearth | — | Crida et al. 2018 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | — | — | Zhang et al. 2021 |
| 2004 | Radial Velocity | McDonald Observatory | 9.2 m Hobby-Eberly Telescope | 0.74 day | — | — | — | Kokori et al. 2023 |