(28978) Ixion
This object has a more recent orbit available here
Object
| Object | (28978) Ixion | 
| Diameter(1) | 617 km | 
| Dynamic class(1) | plutino | 
| Absolute magnitude | 3.60 | 
| G slop | 0.15 | 
(1) Data from the johnston archive list.
Orbital elements
| Epoch (Julian date) | 2458200.5 | 
| Semi major axis | 39.713214 ± 0.000984 au | 
| Eccentricity | 0.242209267 ± 0.000007235 | 
| Inclination | 19.580706130 ± 0.000244282 ° | 
| Longitude of ascending node | 70.991081 ± 0.000368 ° | 
| Argument of perihelia | 298.576718 ± 0.003977 ° | 
| Mean anomaly | 284.990480 ± 0.003992 ° | 
| Orbital period | 250.27 yr | 
Ephemeris & Observations
| Ephemeris version | NIMAv8 | 
| Observation file  | 
omc_ast_NIMAv8.txt | 
| bsp file | 28978_Ixion_nima_v8.bsp | 
| Date of first observation | 1982-07-17 | 
| Date of last observation | 2019-09-28 | 
| Number of observations used in the fit | 430 | 
| Number of rejected observations | 18 | 
| Number of DES observations | 0 | 
| Number of MPC observations | 174 | 
| Number of unpublished observations | 274 | 
| RMS of observations | 0.204 arcsec | 
Residuals
Residuals in right ascension and declination compared to NIMAv8 ephemeris.
 Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
| date | σα (arcsec) | σδ (arcsec) | 
| 2019-01 | 0.062 | 0.024 | 
| 2019-07 | 0.058 | 0.030 | 
| 2020-01 | 0.079 | 0.029 | 
| 2020-07 | 0.077 | 0.036 | 
| 2021-01 | 0.098 | 0.034 | 
| 2021-07 | 0.099 | 0.043 | 
| 2022-01 | 0.120 | 0.040 | 
| 2022-07 | 0.124 | 0.050 | 
| 2023-01 | 0.145 | 0.046 | 
Ephemeris comparison
Difference between NIMAv8 and JPL15 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.