(60558) Echeclus


This object has a more recent orbit available here

Object

Object (60558) Echeclus
Diameter(1) 64 km
Dynamic class(1) Centaur
Absolute magnitude 9.50
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2458600.5
Semi major axis 10.690937 ± 0.000002 au
Eccentricity 0.456454677 ± 0.000000112
Inclination 4.343406390 ± 0.000002733 °
Longitude of ascending node 173.303520 ± 0.000122 °
Argument of perihelia 162.809124 ± 0.000122 °
Mean anomaly 41.343964 ± 0.000015 °
Orbital period 34.96 yr

Ephemeris & Observations

Ephemeris version NIMAv7
Observation file (documentation) omc_ast_NIMAv7.txt
bsp file 60558_Echeclus_nima_v7.bsp
Date of first observation 1979-09-23
Date of last observation 2020-03-21
Number of observations used in the fit 649
Number of rejected observations 3785
Number of DES observations 0
Number of MPC observations 4253
Number of unpublished observations 181
RMS of observations 0.545 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv7 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2020-01 0.005 0.004
2020-07 0.008 0.004
2021-01 0.013 0.007
2021-07 0.015 0.008
2022-01 0.022 0.013
2022-07 0.021 0.013
2023-01 0.029 0.017
2023-07 0.027 0.016
2024-01 0.036 0.021

Ephemeris comparison

residual plot

Difference between NIMAv7 and JPL90 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.