(1871) Astyanax
This object has a more recent orbit available here
Object
| Object | (1871) Astyanax |
| Diameter(1) | 34 km |
| Dynamic class(1) | trojan |
| Absolute magnitude | 11.29 |
| G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
| Epoch (Julian date) | 2456550.165910663 |
| Semi major axis | 5.260894 ± 0.000001 au |
| Eccentricity | 0.032887317 ± 0.000000093 |
| Inclination | 8.596592352 ± 0.000006164 ° |
| Longitude of ascending node | 145.766400 ± 0.000046 ° |
| Argument of perihelia | 166.476499 ± 0.000176 ° |
| Mean anomaly | 47.652295 ± 0.000194 ° |
| Orbital period | 12.07 yr |
Ephemeris & Observations
| Ephemeris version | NIMAv3 |
| Observation file |
omc_ast_NIMAv3.txt |
| bsp file | 1871_Astyanax_nima_v3.bsp |
| Date of first observation | 1971-03-24 |
| Date of last observation | 2020-07-18 |
| Number of observations used in the fit | 1519 |
| Number of rejected observations | 6 |
| Number of DES observations | 40 |
| Number of MPC observations | 1457 |
| Number of unpublished observations | 28 |
| RMS of observations | 0.494 arcsec |
Residuals
Residuals in right ascension and declination compared to NIMAv3 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
| date | σα (arcsec) | σδ (arcsec) |
| 2021-01 | 0.042 | 0.021 |
| 2021-07 | 0.053 | 0.028 |
| 2022-01 | 0.047 | 0.023 |
| 2022-07 | 0.070 | 0.035 |
| 2023-01 | 0.050 | 0.024 |
| 2023-07 | 0.074 | 0.036 |
| 2024-01 | 0.050 | 0.024 |
| 2024-07 | 0.063 | 0.031 |
| 2025-01 | 0.047 | 0.022 |
Ephemeris comparison
Difference between NIMAv3 and JPL37 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.