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
2018-10-23 09:14:40 s 1 +38774.047 0 +341440.30 5560.0 C57
2018-10-23 09:44:40 S 02 23 34.286 -03 02 15.18 V C57
2018-10-23 09:44:40 s 1 +37669.378 0 +342194.01 1310.0 C57
2018-10-23 10:14:40 S 02 23 32.011 -03 02 24.76 V C57
2018-10-23 10:14:40 s 1 +36563.615 0 +342937.39 6840.0 C57
2018-10-23 10:44:40 S 02 23 29.419 -03 02 37.61 V C57
2018-10-23 10:44:40 s 1 +35456.797 0 +343670.46 2400.0 C57
2018-10-23 11:14:40 S 02 23 27.271 -03 02 49.09 V C57
2018-10-23 11:14:40 s 1 +34348.962 0 +344393.25 8250.0 C57
2018-10-23 11:44:40 S 02 23 24.977 -03 02 59.17 V C57
2018-10-23 11:44:40 s 1 +33240.147 0 +345105.78 4610.0 C57
2018-10-23 12:14:40 S 02 23 22.625 -03 03 09.94 V C57
2018-10-23 12:14:40 s 1 +32130.390 0 +345808.07 1730.0 C57
2018-10-23 12:44:40 S 02 23 20.273 -03 03 23.90 V C57
2018-10-23 12:44:40 s 1 +31019.726 0 +346500.14 9840.0 C57
2018-10-23 13:14:40 S 02 23 17.897 -03 03 30.96 V C57
2018-10-23 13:14:40 s 1 +29908.193 0 +347182.00 9190.0 C57
2018-10-23 13:44:40 S 02 23 15.547 -03 03 43.20 V C57
2018-10-23 13:44:40 s 1 +28795.827 0 +347853.69 0.0 C57
2018-10-23 14:14:40 S 02 23 13.426 -03 03 52.02 V C57
2018-10-23 14:14:40 s 1 +27682.663 0 +348515.22 2500.0 C57
2018-10-23 14:44:40 S 02 23 10.831 -03 04 04.04 V C57
2018-10-23 14:44:40 s 1 +26568.738 0 +349166.61 6920.0 C57
2018-10-23 15:14:40 S 02 23 08.503 -03 04 14.88 V C57
2018-10-23 15:14:40 s 1 +25454.086 0 +349807.87 3500.0 C57
2018-10-23 15:44:40 S 02 23 06.348 -03 04 25.00 V C57
2018-10-23 15:44:40 s 1 +24338.742 0 +350439.04 2450.0 C57
2018-10-23 16:14:40 S 02 23 03.845 -03 04 37.78 V C57
2018-10-23 16:14:40 s 1 +23222.742 0 +351060.13 3990.0 C57
2018-10-23 16:44:40 S 02 23 01.843 -03 04 49.80 V C57
2018-10-23 16:44:40 s 1 +22106.120 0 +351671.15 8360.0 C57
2018-10-23 17:14:40 S 02 22 59.230 -03 05 00.38 V C57
2018-10-23 17:14:40 s 1 +20988.910 0 +352272.13 5770.0 C57
2018-10-23 18:14:40 S 02 22 54.614 -03 05 18.71 V C57
2018-10-23 18:14:40 s 1 +18752.862 0 +353444.03 580.0 C57
2018-10-23 18:44:40 S 02 22 52.380 -03 05 31.16 V C57
2018-10-23 18:44:40 s 1 +17634.091 0 +354014.99 8420.0 C57
2018-10-23 19:14:40 S 02 22 50.030 -03 05 44.70 V C57
2018-10-23 19:14:40 s 1 +16514.867 0 +354575.98 150.0 C57
2018-10-23 19:44:40 S 02 22 47.839 -03 05 54.28 V C57
2018-10-23 19:44:40 s 1 +15395.223 0 +355127.01 6010.0 C57
2018-10-23 20:14:40 S 02 22 45.797 -03 06 03.71 V C57
2018-10-23 20:14:40 s 1 +14275.192 0 +355668.11 6190.0 C57
2018-10-23 20:44:40 S 02 22 43.294 -03 06 14.98 V C57
2018-10-23 20:44:40 s 1 +13154.806 0 +356199.29 900.0 C57
2018-10-23 21:14:40 S 02 22 40.949 -03 06 25.31 V C57
2018-10-23 21:14:40 s 1 +12034.097 0 +356720.57 350.0 C57
2018-10-23 21:44:40 S 02 22 38.614 -03 06 34.31 V C57
2018-10-23 21:44:40 s 1 +10913.099 0 +357231.96 4760.0 C57
2018-10-23 22:14:40 S 02 22 36.538 -03 06 47.95 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)