(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 | 11.20 |
| G slop | 0.15 |
(1) Data from the johnston archive list.
Orbital elements
| Epoch (Julian date) | 2458600.5 |
| Semi major axis | 5.242393 ± 0.000001 au |
| Eccentricity | 0.034240430 ± 0.000000081 |
| Inclination | 8.603378482 ± 0.000007359 ° |
| Longitude of ascending node | 145.762789 ± 0.000052 ° |
| Argument of perihelia | 162.799003 ± 0.000218 ° |
| Mean anomaly | 219.347869 ± 0.000191 ° |
| Orbital period | 12.00 yr |
Ephemeris & Observations
| Ephemeris version | NIMAv1 |
| Observation file |
omc_ast_NIMAv1.txt |
| bsp file | 1871_Astyanax_nima_v1.bsp |
| Date of first observation | 1971-03-24 |
| Date of last observation | 2018-04-05 |
| Number of observations used in the fit | 1148 |
| Number of rejected observations | 3 |
| Number of DES observations | 40 |
| Number of MPC observations | 1083 |
| Number of unpublished observations | 28 |
| RMS of observations | 0.531 arcsec |
Residuals
Residuals in right ascension and declination compared to NIMAv1 ephemeris.
Colours indicate the estimated precision in arcsec used as weights in the fitting process.
Orbit quality
| date | σα (arcsec) | σδ (arcsec) |
| 2018-01 | 0.044 | 0.033 |
| 2018-07 | 0.034 | 0.023 |
| 2019-01 | 0.049 | 0.028 |
| 2019-07 | 0.043 | 0.021 |
| 2020-01 | 0.056 | 0.025 |
| 2020-07 | 0.057 | 0.025 |
| 2021-01 | 0.062 | 0.024 |
| 2021-07 | 0.076 | 0.031 |
| 2022-01 | 0.065 | 0.024 |
Ephemeris comparison
Difference between NIMAv1 and JPL22 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.