(911) Agamemnon
This object has a more recent orbit available here
Object
Object | (911) Agamemnon |
Diameter(1) | 131 km |
Dynamic class(1) | trojan |
Absolute magnitude | 8.04 |
G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
Epoch (Julian date) | 2459800.5 |
Semi major axis | 5.281169 ± 0.000000 au |
Eccentricity | 0.067427699 ± 0.000000058 |
Inclination | 21.762045660 ± 0.000007050 ° |
Longitude of ascending node | 338.004799 ± 0.000015 ° |
Argument of perihelia | 81.243785 ± 0.000057 ° |
Mean anomaly | 5.934737 ± 0.000052 ° |
Orbital period | 12.14 yr |
Ephemeris & Observations
Ephemeris version | NIMAv4 |
Observation file |
omc_ast_NIMAv4.txt |
bsp file | 911_Agamemnon_nima_v4.bsp |
Date of first observation | 1919-03-19 |
Date of last observation | 2022-07-16 |
Number of observations used in the fit | 3446 |
Number of rejected observations | 20 |
Number of DES observations | 0 |
Number of MPC observations | 3399 |
Number of unpublished observations | 67 |
RMS of observations | 3.538 arcsec |
Residuals

Residuals in right ascension and declination compared to NIMAv4 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
date | σα (arcsec) | σδ (arcsec) |
2022-01 | 0.025 | 0.025 |
2022-07 | 0.026 | 0.021 |
2023-01 | 0.040 | 0.032 |
2023-07 | 0.032 | 0.024 |
2024-01 | 0.047 | 0.038 |
2024-07 | 0.033 | 0.027 |
2025-01 | 0.042 | 0.041 |
2025-07 | 0.032 | 0.031 |
2026-01 | 0.038 | 0.037 |
Ephemeris comparison

Difference between NIMAv4 and JPL83 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.