(90377) Sedna
This object has a more recent orbit available here
Object
| Object | (90377) Sedna |
| Diameter(1) | 995 km |
| Dynamic class(1) | Sednoid |
| Absolute magnitude | 1.55 |
| G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
| Epoch (Julian date) | 2459800.5 |
| Semi major axis | 521.379210 ± 0.280551 au |
| Eccentricity | 0.853496054 ± 0.000078960 |
| Inclination | 11.930885325 ± 0.000002799 ° |
| Longitude of ascending node | 144.225783 ± 0.000570 ° |
| Argument of perihelia | 310.931951 ± 0.002703 ° |
| Mean anomaly | 358.401789 ± 0.001289 ° |
| Orbital period | 11905.26 yr |
Ephemeris & Observations
| Ephemeris version | NIMAv12 |
| Observation file |
omc_ast_NIMAv12.txt |
| bsp file | 90377_Sedna_nima_v12.bsp |
| Date of first observation | 1990-09-25 |
| Date of last observation | 2023-01-11 |
| Number of observations used in the fit | 509 |
| Number of rejected observations | 40 |
| Number of DES observations | 0 |
| Number of MPC observations | 443 |
| Number of unpublished observations | 106 |
| RMS of observations | 0.260 arcsec |
Residuals
Residuals in right ascension and declination compared to NIMAv12 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
| date | σα (arcsec) | σδ (arcsec) |
| 2023-01 | 0.069 | 0.045 |
| 2023-07 | 0.071 | 0.047 |
| 2024-01 | 0.083 | 0.050 |
| 2024-07 | 0.086 | 0.052 |
| 2025-01 | 0.098 | 0.056 |
| 2025-07 | 0.102 | 0.058 |
| 2026-01 | 0.116 | 0.061 |
| 2026-07 | 0.120 | 0.063 |
| 2027-01 | 0.134 | 0.067 |
Ephemeris comparison
Difference between NIMAv12 and JPL39 in right ascension (weighted by cos δ) and in declination.
Gray area represents the 1-σ uncertainty of NIMA ephemeris. Green dots represent the DES observations.