(884) Priamus


Object

Object (884) Priamus
Diameter(1) 101 km
Dynamic class(1) trojan
Absolute magnitude 8.74
G slop 0.15
(1) Data from the johnston archive list.

Orbital elements

Epoch (Julian date) 2460600.5
Semi major axis 5.207680 ± 0.000000 au
Eccentricity 0.124572235 ± 0.000000031
Inclination 8.895517409 ± 0.000001977 °
Longitude of ascending node 301.458262 ± 0.000011 °
Argument of perihelia 337.472192 ± 0.000022 °
Mean anomaly 96.384859 ± 0.000014 °
Orbital period 11.88 yr

Ephemeris & Observations

Ephemeris version NIMAv8
Observation file (documentation) omc_ast_NIMAv8.txt
bsp file 884_Priamus_nima_v8.bsp
Date of first observation 1917-09-22
Date of last observation 2024-07-13
Number of observations used in the fit 4616
Number of rejected observations 39
Number of DES observations 0
Number of MPC observations 4650
Number of unpublished observations 5
RMS of observations 3.304 arcsec

Residuals

residual plot

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)
2024-01 0.022 0.014
2024-07 0.028 0.013
2025-01 0.031 0.015
2025-07 0.030 0.008
2026-01 0.039 0.011
2026-07 0.030 0.005
2027-01 0.041 0.007
2027-07 0.028 0.008
2028-01 0.036 0.014

Ephemeris comparison

residual plot

Difference between NIMAv8 and JPL63 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