(624) Hektor


This object has a more recent orbit available here

Object

Object (624) Hektor
Diameter(1) 225 km
Dynamic class(1) trojan
Absolute magnitude 7.30
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2458600.5
Semi major axis 5.259580 ± 0.000000 au
Eccentricity 0.023280389 ± 0.000000057
Inclination 18.162463979 ± 0.000003343 °
Longitude of ascending node 342.793765 ± 0.000004 °
Argument of perihelia 185.152979 ± 0.000078 °
Mean anomaly 168.887613 ± 0.000083 °
Orbital period 12.06 yr

Ephemeris & Observations

Ephemeris version NIMAv4
Observation file (documentation) omc_ast_NIMAv4.txt
bsp file 624_Hektor_nima_v4.bsp
Date of first observation 1907-02-11
Date of last observation 2020-09-04
Number of observations used in the fit 2408
Number of rejected observations 72
Number of DES observations 0
Number of MPC observations 2473
Number of unpublished observations 7
RMS of observations 0.571 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)
2020-01 0.004 0.004
2020-07 0.006 0.006
2021-01 0.007 0.008
2021-07 0.010 0.009
2022-01 0.013 0.013
2022-07 0.013 0.011
2023-01 0.020 0.016
2023-07 0.016 0.011
2024-01 0.026 0.017

Ephemeris comparison

residual plot

Difference between NIMAv4 and JPL89 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.