(65489) Ceto


This object has a more recent orbit available here

Object

Object (65489) Ceto
Diameter(1) 223 km
Dynamic class(1) Centaur?
Absolute magnitude 6.40
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2458600.5
Semi major axis 101.650555 ± 0.008350 au
Eccentricity 0.823660987 ± 0.000013444
Inclination 22.293618513 ± 0.000166491 °
Longitude of ascending node 171.986772 ± 0.000301 °
Argument of perihelia 320.096555 ± 0.000941 °
Mean anomaly 10.450945 ± 0.001323 °
Orbital period 1024.88 yr

Ephemeris & Observations

Ephemeris version NIMAv2
Observation file (documentation) omc_ast_NIMAv2.txt
bsp file 65489_Ceto_nima_v2.bsp
Date of first observation 1987-01-31
Date of last observation 2020-05-12
Number of observations used in the fit 225
Number of rejected observations 6
Number of DES observations 0
Number of MPC observations 231
Number of unpublished observations 0
RMS of observations 0.268 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv2 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2021-01 0.114 0.065
2021-07 0.098 0.065
2022-01 0.132 0.068
2022-07 0.115 0.068
2023-01 0.150 0.071
2023-07 0.133 0.071
2024-01 0.169 0.074
2024-07 0.152 0.073
2025-01 0.189 0.077

Ephemeris comparison

residual plot

Difference between NIMAv2 and JPL9 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.