(1583) Antilochus


This object has a more recent orbit available here

Object

Object (1583) Antilochus
Diameter(1) 109 km
Dynamic class(1) trojan
Absolute magnitude 8.60
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2458600.5
Semi major axis 5.132436 ± 0.000000 au
Eccentricity 0.052111563 ± 0.000000058
Inclination 28.511855390 ± 0.000004105 °
Longitude of ascending node 221.376439 ± 0.000011 °
Argument of perihelia 186.805877 ± 0.000086 °
Mean anomaly 291.368262 ± 0.000090 °
Orbital period 11.63 yr

Ephemeris & Observations

Ephemeris version NIMAv1
Observation file (documentation) omc_ast_NIMAv1.txt
bsp file 1583_Antilochus_nima_v1.bsp
Date of first observation 1926-11-10
Date of last observation 2019-01-05
Number of observations used in the fit 2018
Number of rejected observations 20
Number of DES observations 0
Number of MPC observations 2038
Number of unpublished observations 0
RMS of observations 0.556 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv1 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2018-01 0.013 0.012
2018-07 0.019 0.018
2019-01 0.016 0.014
2019-07 0.024 0.018
2020-01 0.023 0.016
2020-07 0.031 0.017
2021-01 0.035 0.018
2021-07 0.036 0.017
2022-01 0.050 0.022

Ephemeris comparison

residual plot

Difference between NIMAv1 and JPL34 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.