Astronomical evidence
55 Cnc e orbits 55 Cnc. The saved catalog gives an orbital period of 0.7365474 (+1.3e-06/−1.4e-06) days. Its discovery method is recorded as radial velocity. These quantities describe the real astronomical setting behind the illustration. 55 Cnc e completes an orbit in less than an Earth day. Its measured size and mass distinguish it from a Jupiter-scale gas giant, while the close orbit makes stellar heating a central part of any physical interpretation. Orbital period, rotation period and atmospheric circulation describe different processes and should not be treated as interchangeable. The catalog radius is 1.875 ± 0.029 Earth radii. The mass entry is 7.99 (+0.32/−0.33) Earth masses. The source papers and full table retain the provenance of each parameter.
The illustrated viewpoint
The enclosed orbital viewpoint is invented. Visible surface texture, molten regions and the spectrum transmitted by a protective window are not determined by the catalog’s bulk parameters.
The enclosed orbital viewpoint is invented. Visible surface texture, molten regions and the spectrum transmitted by a protective window are not determined by the catalog’s bulk parameters. All depicted life and technology are fictional.
Catalog measurements & sources
Host: 55 Cnc. Snapshot: 25 September 2026. Errors, limits and source provenance are retained. Calculated values and model estimates are not direct measurements. Unknown is not zero; equilibrium temperature is not surface temperature.
| Quantity / unit | Value / reported errors | Source |
|---|---|---|
| Radius · Earth radii | 1.875 (+0.029 / -0.029) | Bourrier et al. 2018 |
| Mass · Earth masses | 7.99 (+0.32 / -0.33) | Bourrier et al. 2018 |
| Density · g/cm³ | 6.66 (+0.43 / -0.4) | Bourrier et al. 2018 |
| Orbital period · days | 0.736547 (+1.3e-06 / -1.4e-06) | Bourrier et al. 2018 |
| Orbital semimajor axis · AU | 0.01544 (+5e-05 / -5e-05) | Bourrier et al. 2018 |
| Eccentricity | 0.05 (+0.03 / -0.03) | Bourrier et al. 2018 |
| Inclination · degrees | 83.59 (+0.47 / -0.44) | Bourrier et al. 2018 |
| Irradiation · Earth flux | 2657.83 | ExoFOP |
| Equilibrium temperature · K | 1958 (+15 / -15) | Demory et al. 2011 |
| Stellar effective temperature · K | 5172 (+18 / -18) | Bourrier et al. 2018 |
| Stellar radius · Solar | 0.943 (+0.01 / -0.01) | Bourrier et al. 2018 |
| Stellar mass · Solar | 0.905 (+0.015 / -0.015) | Bourrier et al. 2018 |
| Stellar luminosity · log Solar | -0.19695 (+0.0125 / -0.01039) | Knapp et al. 2020 |
| Stellar age · Gyr | 5.5 (+2.5 / -2.5) | Marcy et al. 2002 |
| Stellar metallicity · dex | 0.35 (+0.1 / -0.1) | Bourrier et al. 2018 |
| Distance · pc | 12.5855 (+0.0124 / -0.0123) | TICv8 |