99942 Apophis (2004 MN4)

NEO PHA MOID ⇩ IMP ⇩ COV ★ EPH ⇩ OBS ⇩ Radar
Orbital Elements
Epoch (TDB)2025-11-21 (JD 2461000.5)
Eccentricity (e)0.1911663196 ± 2.00e+00
Semi-major axis (a)0.9223804710 AU ± 3.00e+00
Inclination (i)3.34095673° ± 4.00e+00
Long. of Asc. Node (Ω)203.89962943° ± 5.00e+00
Arg. of Perihelion (ω)126.67282559° ± 6.00e+00
Mean Anomaly (M)312.80548085° ± 2.46e-06
Mean Motion (n)1.1126206784°/day ± 5.43e+00
Perihelion dist (q)0.74605239 AU ± 3.05e+00
Aphelion dist (Q)1.09870855 AU ± 4.02e+00
Orbital Period0.88586012 yr ± 4.32e+00
NGA Modelr2
A1-3.03172826e-03 AU/d²
A2-2.37461812e-06 AU/d²
Physical Parameters
H (abs. magnitude)19.00
G (slope)0.15
Orbit Solution
SourceIAA
Solution Date2026-04-29
RMS Residual0.213″
Uncertainty0
Orbit TypeAten
MOID0.000007 AU
Observations Used8720
Oppositions2
Arc Total2004-2021
First Observation Used2004-03-15
Last Observation Used2021-05-20
Observations (10797)
Date Type RA Dec Mag Band Observatory
2021-03-03 17:54:05 s 1 -174500.19 7 +269381.79 2170.0 C57
2021-03-03 17:55:20 C 09 37 00.15 -09 24 07.2 V C40
2021-03-03 17:56:53 C 09 36 59.84 -09 24 04.3 V C40
2021-03-03 17:58:25 C 09 36 59.52 -09 24 01.4 V C40
2021-03-03 18:04:05 S 09 38 33.907 -09 39 21.28 V C57
2021-03-03 18:04:05 s 1 -174701.34 0 +268900.29 230.0 C57
2021-03-03 18:08:36 C 09 36 57.46 -09 23 42.8 V C40
2021-03-03 18:14:05 S 09 38 31.498 -09 39 02.38 V C57
2021-03-03 18:14:05 s 1 -174901.73 3 +268417.63 6950.0 C57
2021-03-03 18:24:05 S 09 38 29.138 -09 38 43.58 V C57
2021-03-03 18:24:05 s 1 -175101.37 2 +267933.82 2340.0 C57
2021-03-03 18:34:05 S 09 38 26.825 -09 38 24.47 V C57
2021-03-03 18:34:05 s 1 -175300.25 6 +267448.86 6380.0 C57
2021-03-03 18:44:05 S 09 38 24.454 -09 38 05.42 V C57
2021-03-03 18:44:05 s 1 -175498.38 1 +266962.75 9080.0 C57
2021-03-03 18:54:05 S 09 38 22.085 -09 37 47.35 V C57
2021-03-03 18:54:05 s 1 -175695.74 4 +266475.47 420.0 C57
2021-03-03 19:04:05 S 09 38 19.721 -09 37 28.56 V C57
2021-03-03 19:04:05 s 1 -175892.34 3 +265987.04 400.0 C57
2021-03-03 19:14:05 S 09 38 17.330 -09 37 09.44 V C57
2021-03-03 19:14:05 s 1 -176088.17 4 +265497.45 9010.0 C57
2021-03-03 19:24:05 S 09 38 15.005 -09 36 49.64 V C57
2021-03-03 19:24:05 s 1 -176283.23 4 +265006.71 6250.0 C57
2021-03-03 19:34:05 S 09 38 12.593 -09 36 31.50 V C57
2021-03-03 19:34:05 s 1 -176477.52 0 +264514.80 2110.0 C57
2021-03-03 19:44:05 S 09 38 10.298 -09 36 13.07 V C57
2021-03-03 19:44:05 s 1 -176671.03 0 +264021.73 6590.0 C57
2021-03-03 19:54:05 S 09 38 07.891 -09 35 53.74 V C57
2021-03-03 19:54:05 s 1 -176863.76 1 +263527.49 9680.0 C57
2021-03-03 19:58:15 C 09 36 35.96 -09 20 16.8 V L54
2021-03-03 20:04:05 S 09 38 05.537 -09 35 34.51 V C57
2021-03-03 20:04:05 s 1 -177055.70 9 +263032.10 1380.0 C57
2021-03-03 20:14:05 S 09 38 03.163 -09 35 15.18 V C57
2021-03-03 20:14:05 s 1 -177246.87 1 +262535.54 1680.0 C57
2021-03-03 20:16:36 C 09 36 31.90 -09 19 42.5 V C73
2021-03-03 20:20:33 C 09 36 31.01 -09 19 34.9 V C73
2021-03-03 20:24:05 S 09 38 00.780 -09 34 56.57 V C57
2021-03-03 20:24:05 s 1 -177437.24 4 +262037.81 570.0 C57
2021-03-03 20:24:30 C 09 36 30.20 -09 19 27.9 V C73
2021-03-03 20:28:26 C 09 36 29.40 -09 19 19.8 V C73
2021-03-03 20:32:23 C 09 36 28.61 -09 19 12.7 V C73
2021-03-03 20:34:05 S 09 37 58.421 -09 34 38.35 V C57
2021-03-03 20:34:05 s 1 -177626.82 6 +261538.92 8040.0 C57
2021-03-03 20:36:20 C 09 36 27.80 -09 19 05.5 V C73
2021-03-03 20:40:16 C 09 36 26.98 -09 18 58.0 V C73
2021-03-03 20:44:05 S 09 37 56.090 -09 34 19.16 V C57
2021-03-03 20:44:05 s 1 -177815.61 3 +261038.86 4100.0 C57
2021-03-03 20:44:13 C 09 36 26.21 -09 18 49.8 V C73
2021-03-03 20:48:10 C 09 36 25.37 -09 18 42.8 V C73
2021-03-03 20:52:07 C 09 36 24.55 -09 18 36.4 V C73
Radar Observations (50)
Epoch (UTC)ValueSigmaUnitsFreq (MHz)ReceiverTransmitter
2005-01-27 23:31:00 -100849.1434 0.25 Hz 2380 -1 -1
2005-01-29 00:00:00 192028507.13 4 us 2380 -1 -1
2005-01-29 00:00:00 -102512.9059 0.25 Hz 2380 -1 -1
2005-01-30 00:18:00 195808170.79 4.5 us 2380 -1 -1
2005-01-30 00:18:00 -103799.8178 0.15 Hz 2380 -1 -1
2005-08-07 17:07:00 8186.8 0.2 Hz 2380 -1 -1
2006-05-06 12:49:00 -118256.8 0.1 Hz 2380 -1 -1
2012-12-21 11:10:00 57992.443 0.25 Hz 8560 -14 -14
2012-12-22 11:00:00 102682986.05 0.25 us 8560 -14 -14
2012-12-22 11:00:00 57880.25 0.1 Hz 8560 -14 -14
2013-01-03 09:20:00 97449107.61 0.25 us 8560 -14 -14
2013-01-03 09:20:00 36629.285 0.1 Hz 8560 -14 -14
2013-01-03 10:00:00 97439308.71 3 us 8560 -14 -14
2013-01-03 10:50:00 97428425.46 0.25 us 8560 -14 -14
2013-01-05 08:40:00 30404.009 0.2 Hz 8560 -14 -14
2013-01-05 10:40:00 96911591.52 0.25 us 8560 -14 -14
2013-01-05 10:40:00 20031.16 0.1 Hz 8560 -14 -14
2013-01-05 10:50:00 96910218.03 3 us 8560 -14 -14
2013-01-06 08:20:00 26660.815 0.1 Hz 8560 -14 -14
2013-01-06 09:30:00 20775.144 0.1 Hz 8560 -14 -14
2013-01-08 08:10:00 15496.441 0.1 Hz 8560 -14 -14
2013-01-09 08:00:00 96451449.73 0.2 us 8560 -14 -14
2013-01-09 08:00:00 9670.119 0.1 Hz 8560 -14 -14
2013-01-09 09:20:00 2690.401 0.1 Hz 8560 -14 -14
2013-01-10 08:00:00 96472652.72 0.2 us 8560 -14 -14
2013-01-10 08:00:00 2590.857 0.1 Hz 8560 -14 -14
2013-01-10 09:40:00 96473924.8 0.2 us 8560 -14 -14
2013-01-11 07:20:00 -1589.599 0.2 Hz 8560 -14 -14
2013-01-14 08:10:00 97258343.56 0.2 us 8560 -14 -14
2013-01-14 08:10:00 -30561.776 0.1 Hz 8560 -14 -14
2013-01-14 09:50:00 97283037.17 0.2 us 8560 -14 -14
2013-01-15 06:30:00 -30666.291 0.1 Hz 8560 -14 -14
2013-01-16 06:30:00 98086754 1 us 8560 -14 -14
2013-01-16 06:30:00 -39582.277 0.2 Hz 8560 -14 -14
2013-01-16 07:50:00 -46641.384 0.1 Hz 8560 -14 -14
2013-01-17 06:20:00 -47875.142 0.1 Hz 8560 -14 -14
2013-02-18 00:56:00 -76760.475 0.2 Hz 2380 -1 -1
2013-02-18 01:37:00 157906444.15 0.25 us 2380 -1 -1
2013-02-18 01:37:00 -78041.365 0.2 Hz 2380 -1 -1
2013-02-19 01:08:00 -78105.657 0.2 Hz 2380 -1 -1
2013-02-20 00:38:00 -78070.341 0.2 Hz 2380 -1 -1
2013-02-20 01:26:00 163578875.87 0.25 us 2380 -1 -1
2013-02-20 01:26:00 -79560.965 0.2 Hz 2380 -1 -1
2013-02-21 01:04:00 -79697.13 0.2 Hz 2380 -1 -1
2013-03-15 23:59:00 235220855.07 2 us 2380 -1 -1
2013-03-15 23:59:00 -80977.5254 0.238 Hz 2380 -1 -1
2021-03-03 06:40:00 29329.8 0.4 Hz 8560 -14 -14
2021-03-05 07:00:00 112426746.52 1 us 8560 -14 -14
2021-03-08 02:50:00 112625015.08 1 us 8560 -14 -14
2021-03-11 08:20:00 113796393.86 1 us 8560 -14 -14
Station codes
-14 DSS-14 Goldstone (70-m) -1 Arecibo (305-m, 1963–2020)