(28978) Ixion


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 39.711945 ± 0.000151 au
Eccentricity 0.242212349 ± 0.000002405
Inclination 19.580712312 ± 0.000053700 °
Longitude of ascending node 70.991072 ± 0.000083 °
Argument of perihelia 298.582441 ± 0.000542 °
Mean anomaly 284.984987 ± 0.000797 °
Orbital period 250.26 yr

Ephemeris & Observations

Ephemeris version NIMAv11
Observation file (documentation) omc_ast_NIMAv11.txt
bsp file 28978_Ixion_nima_v11.bsp
Date of first observation 1982-07-17
Date of last observation 2021-04-28
Number of observations used in the fit 447
Number of rejected observations 23
Number of DES observations 0
Number of MPC observations 194
Number of unpublished observations 276
RMS of observations 0.199 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv11 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2020-01 0.004 0.003
2020-07 0.003 0.003
2021-01 0.003 0.003
2021-07 0.004 0.004
2022-01 0.005 0.004
2022-07 0.007 0.005
2023-01 0.008 0.006
2023-07 0.010 0.007
2024-01 0.012 0.008

Ephemeris comparison

residual plot

Difference between NIMAv11 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.

Previous NIMA versions