(9142) Rhesus


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 0.130088175 ± 0.000000073
Inclination 12.804471492 ± 0.000004295 °
Longitude of ascending node 141.187317 ± 0.000029 °
Argument of perihelia 173.167061 ± 0.000069 °
Mean anomaly 232.843594 ± 0.000051 °
Orbital period 11.75 yr

Ephemeris & Observations

Ephemeris version NIMAv4
Observation file (documentation) omc_ast_NIMAv4.txt
bsp file 9142_Rhesus_nima_v4.bsp
Date of first observation 1954-12-22
Date of last observation 2020-08-13
Number of observations used in the fit 1762
Number of rejected observations 14
Number of DES observations 5
Number of MPC observations 1768
Number of unpublished observations 3
RMS of observations 0.417 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv4 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2021-01 0.016 0.013
2021-07 0.026 0.023
2022-01 0.031 0.021
2022-07 0.059 0.036
2023-01 0.046 0.023
2023-07 0.077 0.032
2024-01 0.056 0.019
2024-07 0.066 0.021
2025-01 0.060 0.017

Ephemeris comparison

residual plot

Difference between NIMAv4 and JPL38 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