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
2018-09-25 10:53:27 C 03 16 57.71 +04 43 08.5 U T05
2018-10-01 13:56:47 C 03 05 58.62 +02 34 54.9 U T08
2018-10-01 13:59:38 C 03 05 58.40 +02 34 52.4 U T08
2018-10-01 14:11:19 C 03 05 57.45 +02 34 43.0 U T08
2018-10-01 14:14:02 C 03 05 57.20 +02 34 40.2 U T08
2018-10-01 14:25:47 C 03 05 56.25 +02 34 30.3 U T08
2018-10-03 13:35:18 C 03 02 12.43 +01 55 42.2 U T05
2018-10-03 13:38:14 C 03 02 12.17 +01 55 39.7 U T05
2018-10-03 13:49:47 C 03 02 11.20 +01 55 30.5 U T05
2018-10-03 13:52:34 C 03 02 10.99 +01 55 28.2 U T05
2018-10-03 14:04:13 C 03 02 10.00 +01 55 18.8 U T05
2018-10-03 14:07:00 C 03 02 09.77 +01 55 16.5 U T05
2018-10-03 14:18:48 C 03 02 08.78 +01 55 07.3 U T05
2018-10-03 14:21:33 C 03 02 08.55 +01 55 04.8 U T05
2018-10-04 02:28:41 C 03 01 10.82 +01 45 17.4 o Z22
2018-10-04 02:31:57 C 03 01 10.59 +01 45 14.1 o Z22
2018-10-04 03:31:39 C 03 01 05.53 +01 44 27.6 o Z22
2018-10-04 03:33:21 C 03 01 05.39 +01 44 25.7 o Z22
2018-10-04 03:35:02 C 03 01 05.24 +01 44 24.5 o Z22
2018-10-05 13:28:47 C 02 58 20.50 +01 17 42.0 U T08
2018-10-05 13:43:14 C 02 58 19.26 +01 17 31.5 U T08
2018-10-05 13:57:50 C 02 58 18.06 +01 17 20.0 U T08
2018-10-05 14:12:32 C 02 58 16.80 +01 17 08.3 U T08
2018-10-06 08:25:21 C 02 56 48.31 +01 03 02.6 V 703
2018-10-06 08:33:01 C 02 56 47.66 +01 02 56.5 V 703
2018-10-06 08:40:41 C 02 56 47.01 +01 02 50.9 V 703
2018-10-06 08:48:21 C 02 56 46.33 +01 02 44.4 V 703
2018-10-10 12:31:37 C 02 48 33.563 -00 09 43.39 U F52
2018-10-10 12:50:39 C 02 48 31.915 -00 09 56.53 U F52
2018-10-10 13:09:38 C 02 48 30.278 -00 10 09.57 U F52
2018-10-10 13:28:37 C 02 48 28.637 -00 10 22.64 U F52
2018-10-11 13:01:50 C 02 46 32.12 -00 26 20.1 U T05
2018-10-11 13:17:18 C 02 46 30.79 -00 26 30.5 U T05
2018-10-11 13:32:15 C 02 46 29.52 -00 26 40.5 U T05
2018-10-11 13:47:43 C 02 46 28.18 -00 26 50.7 U T05
2018-10-18 05:16:48 C 02 33 34.91 -02 01 58.9 V 703
2018-10-18 05:24:48 C 02 33 34.24 -02 02 03.0 V 703
2018-10-18 05:32:48 C 02 33 33.61 -02 02 07.6 V 703
2018-10-18 05:40:48 C 02 33 32.96 -02 02 11.8 V 703
2018-10-18 08:30:50 C 02 33 19.06 -02 03 40.5 V G96
2018-10-18 08:38:11 C 02 33 18.46 -02 03 44.3 V G96
2018-10-18 08:45:34 C 02 33 17.86 -02 03 48.1 V G96
2018-10-18 08:52:55 C 02 33 17.26 -02 03 51.9 V G96
2018-10-19 10:14:40 S 02 31 32.148 -02 19 14.23 V C57
2018-10-19 10:14:40 s 1 +128737.74 8 -20807.722 1200.0 C57
2018-10-19 11:14:40 S 02 31 27.000 -02 19 48.90 V C57
2018-10-19 11:14:40 s 1 +131515.88 6 -14916.921 4040.0 C57
2018-10-19 11:44:40 S 02 31 24.444 -02 20 02.51 V C57
2018-10-19 11:44:40 s 1 +132830.35 2 -11962.466 9550.0 C57
2018-10-19 11:58:24 C 02 31 10.52 -02 17 33.1 U T05
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)