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
1991-03-13 04:19:00 C 11 02 36.93 +05 53 41.8 a 691
1991-03-13 04:49:28 C 11 02 34.90 +05 54 03.4 a 691
1991-03-13 05:19:57 C 11 02 32.84 +05 54 25.3 a 691
1991-03-13 09:17:18 C 11 02 16.94 +05 57 16.0 a 691
1991-03-13 09:32:02 A 11 02 15.95 +05 57 25.7 D 691
1991-03-13 09:47:24 C 11 02 14.95 +05 57 37.1 a 691
1991-03-13 09:54:52 C 11 02 14.47 +05 57 42.8 a 691
1991-03-14 06:23:59 A 11 00 54.89 +06 12 33.1 D 691
1991-03-14 06:42:00 A 11 00 53.63 +06 12 45.8 D 691
1991-03-14 07:25:49 C 11 00 50.71 +06 13 18.4 a 691
1991-03-14 07:35:01 C 11 00 50.07 +06 13 25.6 a 691
1991-03-14 07:45:41 C 11 00 49.36 +06 13 33.2 a 691
1991-03-15 09:52:33 C 10 59 06.04 +06 32 39.8 a 691
1991-03-15 09:58:56 C 10 59 05.60 +06 32 44.4 a 691
1991-03-15 10:16:57 C 10 59 04.39 +06 32 57.7 a 691
1991-03-17 06:41:23 A 10 56 07.56 +07 05 54.3 D 691
1991-03-17 06:48:11 A 10 56 07.08 +07 05 59.7 D 691
1991-03-17 07:06:27 A 10 56 05.81 +07 06 13.1 D 691
1991-03-20 06:48:56 A 10 51 16.02 +08 00 15.9 D 691
1991-03-20 06:58:50 A 10 51 15.36 +08 00 23.9 D 691
1991-03-20 07:14:56 A 10 51 14.23 +08 00 35.8 D 691
1991-04-05 06:17:37 C 10 26 39.84 +12 44 45.3 a 691
1991-04-05 06:28:15 C 10 26 39.21 +12 44 52.6 a 691
1991-04-05 06:46:51 C 10 26 38.11 +12 45 05.4 a 691
1991-04-18 04:18:00 C 10 12 23.35 +15 55 18.0 a 691
1991-04-18 04:24:38 C 10 12 23.09 +15 55 21.4 a 691
1991-04-18 04:40:16 C 10 12 22.50 +15 55 29.7 a 691
1991-05-10 03:34:18 C 10 07 01.91 +19 14 53.4 a 691
1991-05-10 03:54:31 C 10 07 02.11 +19 14 58.0 a 691
1991-05-10 04:16:15 C 10 07 02.30 +19 15 03.9 a 691
1991-05-19 03:21:15 A 10 11 49.14 +19 55 32.7 D 691
1991-05-19 03:36:37 A 10 11 49.60 +19 55 35.4 D 691
1991-05-19 04:24:41 A 10 11 50.89 +19 55 42.1 D 691
1991-06-05 04:21:19 C 10 30 23.78 +20 23 13.7 a 691
1991-06-05 04:28:26 C 10 30 24.16 +20 23 13.8 a 691
1991-06-05 04:53:30 C 10 30 25.61 +20 23 13.1 a 691
1991-08-27 09:26:15 A 14 10 03.91 +17 08 03.8 413
1991-08-29 09:35:24 A 14 31 13.01 +16 24 26.2 413
1991-09-01 04:41:03 A 15 13 22.03 +14 29 08.3 i 691
1991-09-01 05:04:14 A 15 13 39.65 +14 28 11.1 i 691
1991-09-02 19:41:02 A 15 48 05.52 +12 31 09.6 046
1991-09-02 19:47:33 A 15 48 11.37 +12 30 47.1 046
1991-09-03 09:03:00 A 16 02 12.07 +11 40 48.8 474
1991-09-03 09:13:31 A 16 02 23.31 +11 40 02.7 474
1991-09-03 09:31:01 A 16 02 42.37 +11 38 45.9 474
1991-09-03 19:29:02 A 16 14 04.76 +10 50 24.3 046
1991-09-03 19:34:02 A 16 14 10.66 +10 50 01.8 046
1991-09-04 03:43:04 A 16 23 59.89 +10 09 53.8 14.0 675
1991-09-04 04:21:59 A 16 24 47.47 +10 06 25.5 675
1991-09-04 07:53:30 A 16 29 14.84 +09 50 40.5 474
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)