(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 8.19
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2458600.5
Semi major axis 5.215835 ± 0.000000 au
Eccentricity 0.138429535 ± 0.000000011
Inclination 22.048314939 ± 0.000000498 °
Longitude of ascending node 44.351819 ± 0.000005 °
Argument of perihelia 307.949112 ± 0.000004 °
Mean anomaly 203.758486 ± 0.000013 °
Orbital period 11.91 yr

Ephemeris & Observations

Ephemeris version NIMAv2
Observation file (documentation) omc_ast_NIMAv2.txt
bsp file 617_Patroclus_nima_v2.bsp
Date of first observation 1906-10-17
Date of last observation 2019-07-21
Number of observations used in the fit 2680
Number of rejected observations 56
Number of DES observations 0
Number of MPC observations 2697
Number of unpublished observations 0
RMS of observations 0.109 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv2 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2019-01 0.013 0.011
2019-07 0.013 0.012
2020-01 0.018 0.015
2020-07 0.021 0.020
2021-01 0.025 0.017
2021-07 0.034 0.026
2022-01 0.034 0.012
2022-07 0.055 0.013
2023-01 0.040 0.002

Ephemeris comparison

residual plot

Difference between NIMAv2 and JPL54 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.