9856 (1991 EE)

NEO PHA MOID ⇩ IMP ⇩ COV ★ EPH ⇩ OBS ⇩ Radar
Orbital Elements
Epoch (TDB)2025-11-21 (JD 2461000.5)
Eccentricity (e)0.6257509426 ± 7.34e-09
Semi-major axis (a)2.2428520810 AU ± 9.38e-10
Inclination (i)9.82869445° ± 3.18e-06
Long. of Asc. Node (Ω)168.09783490° ± 1.15e-05
Arg. of Perihelion (ω)116.19754724° ± 1.16e-05
Mean Anomaly (M)72.00292090° ± 1.73e-06
Mean Motion (n)0.2934346040°/day ± 1.84e-10
Perihelion dist (q)0.83938528 AU ± 1.65e-08
Aphelion dist (Q)3.64631888 AU ± 1.65e-08
Orbital Period3.35892996 yr ± 2.11e-09
Physical Parameters
H (abs. magnitude)17.08
G (slope)0.15
Orbit Solution
SourceIAA
Solution Date2026-05-31
RMS Residual0.450″
Uncertainty0
Orbit TypeApollo
MOID0.021767 AU
Observations Used1349
Radar Obs Used4
Oppositions1
Arc Total1991-2026
First Observation Used1991-03-13
Last Observation Used2026-02-04
Observations (1824)
Date Type RA Dec Mag Band Observatory
2018-10-21 05:32:33 C 02 28 00.63 -02 37 18.5 V 703
2018-10-21 05:44:40 S 02 27 48.262 -02 41 14.86 V C57
2018-10-21 05:44:40 s 1 +136877.73 3 +203185.69 0.837 C57
2018-10-21 06:14:40 S 02 27 45.830 -02 41 27.67 V C57
2018-10-21 06:14:40 s 1 +136205.45 0 +205166.29 0.427 C57
2018-10-21 07:44:40 S 02 27 38.138 -02 42 05.36 V C57
2018-10-21 07:44:40 s 1 +134134.30 5 +211025.11 0.097 C57
2018-10-21 08:14:40 S 02 27 35.580 -02 42 20.30 V C57
2018-10-21 08:14:40 s 1 +133426.34 7 +212950.52 0.935 C57
2018-10-21 12:14:40 S 02 27 15.394 -02 44 05.28 V C57
2018-10-21 12:14:40 s 1 +127467.49 8 +227864.41 0.563 C57
2018-10-21 12:44:40 S 02 27 13.140 -02 44 16.19 V C57
2018-10-21 12:44:40 s 1 +126687.82 2 +229668.10 0.148 C57
2018-10-21 13:14:40 S 02 27 10.433 -02 44 31.88 V C57
2018-10-21 13:14:40 s 1 +125900.84 7 +231458.47 0.781 C57
2018-10-21 15:14:40 S 02 27 00.413 -02 45 23.22 V C57
2018-10-21 15:14:40 s 1 +122682.43 2 +238487.70 0.313 C57
2018-10-21 15:44:40 S 02 26 57.876 -02 45 35.42 V C57
2018-10-21 15:44:40 s 1 +121860.79 9 +240212.15 0.314 C57
2018-10-21 16:44:40 S 02 26 52.800 -02 46 01.99 V C57
2018-10-21 16:44:40 s 1 +120197.90 5 +243621.92 0.86 C57
2018-10-21 17:14:40 S 02 26 50.537 -02 46 14.77 V C57
2018-10-21 17:14:40 s 1 +119356.86 8 +245307.32 0.543 C57
2018-10-21 18:44:40 S 02 26 42.953 -02 46 52.72 V C57
2018-10-21 18:44:40 s 1 +116796.70 0 +250286.11 380.0 C57
2018-10-21 19:14:40 S 02 26 40.327 -02 47 06.32 V C57
2018-10-21 19:14:40 s 1 +115931.30 9 +251920.04 9030.0 C57
2018-10-21 19:44:40 S 02 26 38.016 -02 47 17.99 V C57
2018-10-21 19:44:40 s 1 +115060.08 8 +253541.20 7260.0 C57
2018-10-21 20:14:40 S 02 26 35.534 -02 47 30.19 V C57
2018-10-21 20:14:40 s 1 +114183.13 8 +255149.64 5680.0 C57
2018-10-21 20:44:40 S 02 26 33.036 -02 47 45.13 V C57
2018-10-21 20:44:40 s 1 +113300.55 7 +256745.39 4900.0 C57
2018-10-21 21:14:40 S 02 26 30.499 -02 47 56.62 V C57
2018-10-21 21:14:40 s 1 +112412.44 1 +258328.51 5540.0 C57
2018-10-21 21:44:40 S 02 26 28.186 -02 48 11.02 V C57
2018-10-21 21:44:40 s 1 +111518.88 7 +259899.02 8200.0 C57
2018-10-21 22:14:40 S 02 26 25.795 -02 48 20.92 V C57
2018-10-21 22:14:40 s 1 +110619.98 8 +261456.97 3450.0 C57
2018-10-22 01:44:40 S 02 26 08.074 -02 49 51.74 V C57
2018-10-22 01:44:40 s 1 +104185.60 7 +272014.29 610.0 C57
2018-10-22 02:44:40 S 02 26 03.082 -02 50 13.74 V C57
2018-10-22 02:44:40 s 1 +102304.13 5 +274919.88 540.0 C57
2018-10-22 03:14:40 S 02 26 00.876 -02 50 24.79 V C57
2018-10-22 03:14:40 s 1 +101356.63 3 +276354.40 2290.0 C57
2018-10-22 03:44:40 S 02 25 58.375 -02 50 38.62 V C57
2018-10-22 03:44:40 s 1 +100404.72 7 +277776.79 2570.0 C57
2018-10-22 04:14:40 S 02 25 55.846 -02 50 49.74 V C57
2018-10-22 04:14:40 s 1 +99448.495 0 +279187.09 1870.0 C57
2018-10-22 04:44:40 S 02 25 53.410 -02 51 02.41 V C57
Radar Observations (8)
Epoch (UTC)ValueSigmaUnitsFreq (MHz)ReceiverTransmitter
1991-09-04 21:43:00 108192.3 1 Hz 2380 -1 -1
1991-09-04 22:36:00 59429989.3 2 us 2380 -1 -1
1991-09-04 22:50:00 59392933.7 0.4 us 2380 -1 -1
1991-09-04.904861 10819230 100 Hz 2380 251 251
1991-09-04.941667 5942998930 2000 us 2380 251 251
1991-09-04.951389 5939293370 400 us 2380 251 251
1991-09-05 22:08:00 56320461 4 us 2380 -1 -1
1991-09-05.922222 5632046100 4000 us 2380 251 251
Station codes
-1 Arecibo (305-m, 1963–2020)