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
2021-01-28 21:01:01 C 11 34 11.28 -19 15 54.6 V 217
2021-01-28 21:02:07 C 11 34 11.20 -19 15 54.9 V 217
2021-01-28 21:03:15 C 11 34 11.13 -19 15 55.1 V 217
2021-01-28 21:04:21 C 11 34 11.05 -19 15 55.4 V 217
2021-01-28 21:05:29 C 11 34 10.97 -19 15 55.7 V 217
2021-01-28 21:06:35 C 11 34 10.90 -19 15 55.9 V 217
2021-01-28 21:07:43 C 11 34 10.81 -19 15 56.2 V 217
2021-01-28 21:08:49 C 11 34 10.74 -19 15 56.5 V 217
2021-01-28 21:09:57 C 11 34 10.66 -19 15 56.8 V 217
2021-01-28 21:11:05 C 11 34 10.58 -19 15 57.1 V 217
2021-01-28 21:12:11 C 11 34 10.50 -19 15 57.3 V 217
2021-01-28 21:13:19 C 11 34 10.42 -19 15 57.6 V 217
2021-01-28 21:14:25 C 11 34 10.36 -19 15 57.8 V 217
2021-01-28 21:15:33 C 11 34 10.27 -19 15 58.1 V 217
2021-01-28 21:16:39 C 11 34 10.19 -19 15 58.4 V 217
2021-01-28 21:17:47 C 11 34 10.11 -19 15 58.6 V 217
2021-01-28 21:18:53 C 11 34 10.04 -19 15 59.0 V 217
2021-01-28 21:20:00 C 11 34 09.96 -19 15 59.1 V 217
2021-01-28 21:21:08 C 11 34 09.88 -19 15 59.4 V 217
2021-01-28 21:22:14 C 11 34 09.80 -19 15 59.7 V 217
2021-01-28 21:23:22 C 11 34 09.73 -19 16 00.0 V 217
2021-01-28 21:24:28 C 11 34 09.66 -19 16 00.2 V 217
2021-01-28 21:29:53 C 11 34 09.28 -19 16 01.5 V 217
2021-01-28 21:31:01 C 11 34 09.19 -19 16 01.7 V 217
2021-01-28 21:32:09 C 11 34 09.11 -19 16 02.0 V 217
2021-01-28 21:33:15 C 11 34 09.03 -19 16 02.3 V 217
2021-01-28 21:34:23 C 11 34 08.96 -19 16 02.5 V 217
2021-01-28 21:35:29 C 11 34 08.89 -19 16 02.8 V 217
2021-01-28 21:36:37 C 11 34 08.80 -19 16 03.0 V 217
2021-01-28 21:37:43 C 11 34 08.72 -19 16 03.2 V 217
2021-01-28 21:38:51 C 11 34 08.64 -19 16 03.5 V 217
2021-01-28 21:39:59 C 11 34 08.57 -19 16 03.8 V 217
2021-01-28 21:41:05 C 11 34 08.50 -19 16 04.0 V 217
2021-01-28 21:42:13 C 11 34 08.41 -19 16 04.2 V 217
2021-01-28 21:43:19 C 11 34 08.34 -19 16 04.5 V 217
2021-01-28 21:44:27 C 11 34 08.26 -19 16 04.8 V 217
2021-01-28 21:45:33 C 11 34 08.18 -19 16 05.1 V 217
2021-01-28 21:46:41 C 11 34 08.11 -19 16 05.3 V 217
2021-01-28 21:47:47 C 11 34 08.03 -19 16 05.6 V 217
2021-01-28 21:48:55 C 11 34 07.95 -19 16 05.8 V 217
2021-01-28 21:50:03 C 11 34 07.86 -19 16 06.1 V 217
2021-01-28 21:51:09 C 11 34 07.79 -19 16 06.3 V 217
2021-01-28 21:52:17 C 11 34 07.72 -19 16 06.5 V 217
2021-01-28 21:53:23 C 11 34 07.63 -19 16 06.8 V 217
2021-01-28 21:54:31 C 11 34 07.56 -19 16 07.1 V 217
2021-01-28 21:55:37 C 11 34 07.48 -19 16 07.3 V 217
2021-01-28 21:56:45 C 11 34 07.40 -19 16 07.6 V 217
2021-01-28 21:57:52 C 11 34 07.32 -19 16 07.9 V 217
2021-01-28 21:58:58 C 11 34 07.25 -19 16 08.1 V 217
2021-01-28 22:00:07 C 11 34 07.17 -19 16 08.4 V 217
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)