(617) Patroclus


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 0.139533380 ± 0.000000026
Inclination 22.064856386 ± 0.000002683 °
Longitude of ascending node 44.349939 ± 0.000003 °
Argument of perihelia 308.672200 ± 0.000013 °
Mean anomaly 25.589971 ± 0.000012 °
Orbital period 11.88 yr

Ephemeris & Observations

Ephemeris version NIMAv10
Observation file (documentation) omc_ast_NIMAv10.txt
bsp file 617_Patroclus_nima_v10.bsp
Date of first observation 1906-10-17
Date of last observation 2025-10-05
Number of observations used in the fit 6433
Number of rejected observations 40
Number of DES observations 0
Number of MPC observations 6447
Number of unpublished observations 26
RMS of observations 1.370 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv10 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2024-01 0.012 0.010
2024-07 0.015 0.014
2025-01 0.015 0.014
2025-07 0.017 0.014
2026-01 0.020 0.019
2026-07 0.020 0.011
2027-01 0.030 0.015
2027-07 0.023 0.007
2028-01 0.033 0.011

Ephemeris comparison

residual plot

Difference between NIMAv10 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.

Previous NIMA versions