(5638) Deikoon
This object has a more recent orbit available here
Object
Object | (5638) Deikoon |
Diameter(1) | 47 km |
Dynamic class(1) | trojan |
Absolute magnitude | 10.50 |
G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
Epoch (Julian date) | 2458200.5 |
Semi major axis | 5.248985 ± 0.000001 au |
Eccentricity | 0.107235528 ± 0.000000070 |
Inclination | 10.908380976 ± 0.000007755 ° |
Longitude of ascending node | 156.019745 ± 0.000042 ° |
Argument of perihelia | 91.816592 ± 0.000094 ° |
Mean anomaly | 260.334578 ± 0.000079 ° |
Orbital period | 12.03 yr |
Ephemeris & Observations
Ephemeris version | NIMAv2 |
Observation file |
omc_ast_NIMAv2.txt |
bsp file | 5638_Deikoon_nima_v2.bsp |
Date of first observation | 1988-08-18 |
Date of last observation | 2019-02-12 |
Number of observations used in the fit | 1453 |
Number of rejected observations | 4 |
Number of DES observations | 10 |
Number of MPC observations | 1447 |
Number of unpublished observations | 0 |
RMS of observations | 0.510 arcsec |
Residuals

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) |
2018-01 | 0.041 | 0.033 |
2018-07 | 0.032 | 0.023 |
2019-01 | 0.048 | 0.029 |
2019-07 | 0.043 | 0.023 |
2020-01 | 0.059 | 0.027 |
2020-07 | 0.065 | 0.030 |
2021-01 | 0.069 | 0.027 |
2021-07 | 0.096 | 0.038 |
2022-01 | 0.073 | 0.026 |
Ephemeris comparison

Difference between NIMAv2 and JPL21 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.