(617) Patroclus
This object has a more recent orbit available here
Object
| Object | (617) Patroclus |
| Diameter(1) | 140 km |
| Dynamic class(1) | trojan |
| Absolute magnitude | 8.33 |
| G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
| Epoch (Julian date) | 2460800.5 |
| Semi major axis | 5.206045 ± 0.000000 au |
| Eccentricity | 0.139533416 ± 0.000000052 |
| Inclination | 22.064852194 ± 0.000005132 ° |
| Longitude of ascending node | 44.349937 ± 0.000014 ° |
| Argument of perihelia | 308.672201 ± 0.000021 ° |
| Mean anomaly | 25.589967 ± 0.000018 ° |
| Orbital period | 11.88 yr |
Ephemeris & Observations
| Ephemeris version | NIMAv8 |
| Observation file |
omc_ast_NIMAv8.txt |
| bsp file | 617_Patroclus_nima_v8.bsp |
| Date of first observation | 1906-10-17 |
| Date of last observation | 2025-07-13 |
| Number of observations used in the fit | 6170 |
| Number of rejected observations | 28 |
| Number of DES observations | 0 |
| Number of MPC observations | 6198 |
| Number of unpublished observations | 0 |
| RMS of observations | 1.398 arcsec |
Residuals
Residuals in right ascension and declination compared to NIMAv8 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
| date | σα (arcsec) | σδ (arcsec) |
| 2024-01 | 0.025 | 0.018 |
| 2024-07 | 0.027 | 0.026 |
| 2025-01 | 0.027 | 0.025 |
| 2025-07 | 0.027 | 0.024 |
| 2026-01 | 0.033 | 0.031 |
| 2026-07 | 0.028 | 0.020 |
| 2027-01 | 0.040 | 0.028 |
| 2027-07 | 0.028 | 0.017 |
| 2028-01 | 0.038 | 0.023 |
Ephemeris comparison
Difference between NIMAv8 and JPL82 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.