(588) Achilles
Object
| Object |
(588) Achilles |
| Diameter(1) |
130 km |
| Dynamic class(1) |
trojan |
| Absolute magnitude |
8.32 |
| G slop |
0.15 |
Orbital elements
| Epoch (Julian date) |
2460600.5 |
| Semi major axis |
5.212198 ± 0.000000 au |
| Eccentricity |
0.148450053 ± 0.000000041 |
| Inclination |
10.317503932 ± 0.000003969 ° |
| Longitude of ascending node |
316.539333 ± 0.000018 ° |
| Argument of perihelia |
133.984316 ± 0.000027 ° |
| Mean anomaly |
43.908675 ± 0.000016 ° |
| Orbital period |
11.90 yr |
Ephemeris & Observations
| Ephemeris version |
NIMAv8 |
| Observation file (documentation) |
omc_ast_NIMAv8.txt |
| bsp file |
588_Achilles_nima_v8.bsp |
| Date of first observation |
1906-02-22 |
| Date of last observation |
2024-06-06 |
| Number of observations used in the fit |
4343 |
| Number of rejected observations |
44 |
| Number of DES observations |
0 |
| Number of MPC observations |
4323 |
| Number of unpublished observations |
64 |
| RMS of observations |
3.604 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) |
| 2024-01 |
0.030 |
0.021 |
| 2024-07 |
0.022 |
0.014 |
| 2025-01 |
0.032 |
0.021 |
| 2025-07 |
0.027 |
0.018 |
| 2026-01 |
0.034 |
0.019 |
| 2026-07 |
0.034 |
0.021 |
| 2027-01 |
0.035 |
0.016 |
| 2027-07 |
0.041 |
0.021 |
| 2028-01 |
0.034 |
0.015 |
Ephemeris comparison
Difference between NIMAv8 and JPL109 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