(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 | 11.27 |
| G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
| Epoch (Julian date) | 2459800.5 |
| Semi major axis | 5.230045 ± 0.000000 au |
| Eccentricity | 0.034907105 ± 0.000000055 |
| Inclination | 8.606205565 ± 0.000005998 ° |
| Longitude of ascending node | 145.778031 ± 0.000046 ° |
| Argument of perihelia | 166.200103 ± 0.000117 ° |
| Mean anomaly | 314.702906 ± 0.000108 ° |
| Orbital period | 11.96 yr |
Ephemeris & Observations
| Ephemeris version | NIMAv5 |
| Observation file |
omc_ast_NIMAv5.txt |
| bsp file | 1871_Astyanax_nima_v5.bsp |
| Date of first observation | 1971-03-24 |
| Date of last observation | 2023-06-26 |
| Number of observations used in the fit | 2240 |
| Number of rejected observations | 166 |
| Number of DES observations | 20 |
| Number of MPC observations | 2358 |
| Number of unpublished observations | 28 |
| RMS of observations | 0.493 arcsec |
Residuals
Residuals in right ascension and declination compared to NIMAv5 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
| date | σα (arcsec) | σδ (arcsec) |
| 2023-01 | 0.033 | 0.022 |
| 2023-07 | 0.052 | 0.034 |
| 2024-01 | 0.037 | 0.023 |
| 2024-07 | 0.051 | 0.030 |
| 2025-01 | 0.040 | 0.022 |
| 2025-07 | 0.048 | 0.025 |
| 2026-01 | 0.045 | 0.022 |
| 2026-07 | 0.046 | 0.021 |
| 2027-01 | 0.054 | 0.026 |
Ephemeris comparison
Difference between NIMAv5 and JPL45 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.