(9142) Rhesus
This object has a more recent orbit available here
Object
Object | (9142) Rhesus |
Diameter(1) | 45 km |
Dynamic class(1) | trojan |
Absolute magnitude | 10.60 |
G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
Epoch (Julian date) | 2458600.5 |
Semi major axis | 5.168449 ± 0.000000 au |
Eccentricity | 0.130088186 ± 0.000000075 |
Inclination | 12.804473188 ± 0.000004549 ° |
Longitude of ascending node | 141.187314 ± 0.000028 ° |
Argument of perihelia | 173.167065 ± 0.000068 ° |
Mean anomaly | 232.843591 ± 0.000051 ° |
Orbital period | 11.75 yr |
Ephemeris & Observations
Ephemeris version | NIMAv3 |
Observation file |
omc_ast_NIMAv3.txt |
bsp file | 9142_Rhesus_nima_v3.bsp |
Date of first observation | 1954-12-22 |
Date of last observation | 2020-07-14 |
Number of observations used in the fit | 1754 |
Number of rejected observations | 13 |
Number of DES observations | 5 |
Number of MPC observations | 1760 |
Number of unpublished observations | 2 |
RMS of observations | 0.417 arcsec |
Residuals

Residuals in right ascension and declination compared to NIMAv3 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
date | σα (arcsec) | σδ (arcsec) |
2020-01 | 0.007 | 0.007 |
2020-07 | 0.008 | 0.010 |
2021-01 | 0.017 | 0.014 |
2021-07 | 0.027 | 0.024 |
2022-01 | 0.032 | 0.022 |
2022-07 | 0.061 | 0.036 |
2023-01 | 0.047 | 0.023 |
2023-07 | 0.078 | 0.031 |
2024-01 | 0.057 | 0.018 |
Ephemeris comparison

Difference between NIMAv3 and JPL26 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.