Astronomical evidence
HD 80606 b follows an extremely eccentric orbit, spending most of its long year far from its star before making a rapid close passage. Its orbital period is about 111 days. Orbital eccentricity changes the distance to the star and therefore the incident energy; the planet does not receive a nearly constant stellar input throughout its orbit. [1] Spitzer followed the system for about thirty hours around a close approach in November 2007, measuring infrared light at a wavelength of eight micrometres. Just before closest approach, the planet passed behind the star from Earth’s viewpoint. That eclipse helped separate the planetary contribution from the much brighter stellar signal. [2] The measurements showed rapid heating as the planet approached its host. Interpreting the changing brightness requires an atmospheric response model: heat can be absorbed, transported and emitted on different timescales. The observations did not resolve individual storm fronts. Here the sweep of warm color translates a time-dependent energy response into a single interpretive image. [2]
The illustrated viewpoint
Humanoid / eyeless silver-shelled sovereign. An invented orbital shelter near HD 80606 b during a conceptual periastron passage. Spitzer measured a rapid change in infrared brightness near closest approach. The glowing atmospheric sweep visualizes that response rather than a mapped weather front or literal fire. The close stellar vista, colors, timing and thermal pattern are illustrative. The shelter and humanoid are fictional.
Spitzer measured a rapid change in infrared brightness near closest approach. The glowing atmospheric sweep visualizes that response rather than a mapped weather front or literal fire. The close stellar vista, colors, timing and thermal pattern are illustrative. The shelter and humanoid are fictional. All beings, civilizations and technology are fictional. No motives, moral alignment or character history is asserted.
Catalog measurements & sources
Host: HD 80606. 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 | 11.5677 (+0.168135 / -0.168135) | Pearson et al. 2022 |
| Mass · Earth masses | 1323.47 (+1.49379 / -1.49379) | Pearson et al. 2022 |
| Density · g/cm³ | 5.08 (+0.32 / -0.32) | Southworth 2011 |
| Orbital period · days | 111.437 (+7.4e-05 / -7.4e-05) | Pearson et al. 2022 |
| Orbital semimajor axis · AU | 0.4603 (+0.0021 / -0.0021) | Pearson et al. 2022 |
| Eccentricity | 0.93183 (+0.00014 / -0.00014) | Pearson et al. 2022 |
| Inclination · degrees | 89.24 (+0.01 / -0.01) | Pearson et al. 2022 |
| Irradiation · Earth flux | 4.6941 (+0.1147 / -0.1147) | Calculated Value |
| Equilibrium temperature · K | 405 (+7 / -7) | Southworth 2011 |
| Stellar effective temperature · K | 5565 | Pearson et al. 2022 |
| Stellar radius · Solar | 1.05 (+0.01 / -0.01) | Pearson et al. 2022 |
| Stellar mass · Solar | 1.05 | Pearson et al. 2022 |
| Stellar luminosity · log Solar | -0.00237 (+0.00874 / -0.01095) | Wittenmyer et al. 2007 |
| Stellar age · Gyr | 5.9 (+1.6 / -2) | Bonomo et al. 2017 |
| Stellar metallicity · dex | 0.35 | Pearson et al. 2022 |
| Distance · pc | 66.4711 (+0.1612 / -0.1604) | TICv8 |