(5145) Pholus
Object
Object |
(5145) Pholus |
Diameter(1) |
107 km |
Dynamic class(1) |
Centaur |
Absolute magnitude |
6.96 |
G slop |
0.15 |
Orbital elements
Epoch (Julian date) |
2460400.5 |
Semi major axis |
20.284180 ± 0.000025 au |
Eccentricity |
0.573579989 ± 0.000000270 |
Inclination |
24.711054849 ± 0.000015623 ° |
Longitude of ascending node |
119.334415 ± 0.000017 ° |
Argument of perihelia |
354.619372 ± 0.000089 ° |
Mean anomaly |
128.300316 ± 0.000257 ° |
Orbital period |
91.36 yr |
Ephemeris & Observations
Ephemeris version |
NIMAv2 |
Observation file (documentation) |
omc_ast_NIMAv2.txt |
bsp file |
5145_Pholus_nima_v2.bsp |
Date of first observation |
1977-07-22 |
Date of last observation |
2024-05-19 |
Number of observations used in the fit |
394 |
Number of rejected observations |
4 |
Number of DES observations |
0 |
Number of MPC observations |
396 |
Number of unpublished observations |
2 |
RMS of observations |
0.569 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) |
2024-01 |
0.008 |
0.007 |
2024-07 |
0.008 |
0.007 |
2025-01 |
0.007 |
0.007 |
2025-07 |
0.008 |
0.008 |
2026-01 |
0.009 |
0.009 |
2026-07 |
0.012 |
0.009 |
2027-01 |
0.014 |
0.010 |
2027-07 |
0.018 |
0.011 |
2028-01 |
0.020 |
0.012 |
Ephemeris comparison
Difference between NIMAv2 and JPL23 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