(90377) Sedna


Object

Object (90377) Sedna
Diameter(1) 995 km
Dynamic class(1) Sednoid
Absolute magnitude 1.54
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2460600.5
Semi major axis 552.175903 ± 0.306260 au
Eccentricity 0.861812959 ± 0.000076652
Inclination 11.927724262 ± 0.000003010 °
Longitude of ascending node 144.394633 ± 0.000555 °
Argument of perihelia 310.875575 ± 0.002615 °
Mean anomaly 358.594474 ± 0.001171 °
Orbital period 12975.51 yr

Ephemeris & Observations

Ephemeris version NIMAv13
Observation file (documentation) omc_ast_NIMAv13.txt
bsp file 90377_Sedna_nima_v13.bsp
Date of first observation 1990-09-25
Date of last observation 2024-03-18
Number of observations used in the fit 565
Number of rejected observations 40
Number of DES observations 0
Number of MPC observations 499
Number of unpublished observations 106
RMS of observations 0.250 arcsec

Residuals

residual plot

Residuals in right ascension and declination compared to NIMAv13 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.

Orbit quality

date σα (arcsec) σδ (arcsec)
2024-01 0.077 0.049
2024-07 0.080 0.051
2025-01 0.092 0.054
2025-07 0.095 0.056
2026-01 0.108 0.059
2026-07 0.113 0.061
2027-01 0.126 0.065
2027-07 0.132 0.067
2028-01 0.145 0.070

Ephemeris comparison

residual plot

Difference between NIMAv13 and JPL42 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