(60558) Echeclus


Object

Object (60558) Echeclus
Diameter(1) 64 km
Dynamic class(1) Centaur
Absolute magnitude 9.18
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2459800.5
Semi major axis 10.736711 ± 0.000001 au
Eccentricity 0.457248066 ± 0.000000078
Inclination 4.343841522 ± 0.000000789 °
Longitude of ascending node 173.190430 ± 0.000048 °
Argument of perihelia 163.315390 ± 0.000048 °
Mean anomaly 74.560110 ± 0.000017 °
Orbital period 35.18 yr

Ephemeris & Observations

Ephemeris version NIMAv9
Observation file (documentation) omc_ast_NIMAv9.txt
bsp file 60558_Echeclus_nima_v9.bsp
Date of first observation 1979-09-23
Date of last observation 2021-12-31
Number of observations used in the fit 4403
Number of rejected observations 180
Number of DES observations 0
Number of MPC observations 4401
Number of unpublished observations 182
RMS of observations 0.465 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv9 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2022-01 0.007 0.005
2022-07 0.007 0.005
2023-01 0.010 0.006
2023-07 0.010 0.006
2024-01 0.014 0.008
2024-07 0.013 0.007
2025-01 0.017 0.009
2025-07 0.016 0.008
2026-01 0.021 0.010

Ephemeris comparison

residual plot

Difference between NIMAv9 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.

Previous NIMA versions