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
2021-03-06 18:26:40 C 09 23 30.76 -07 03 17.8 V A84
2021-03-06 18:28:29 C 09 23 30.39 -07 03 14.2 V A84
2021-03-06 18:30:28 C 09 23 30.83 -07 03 15.2 V K83
2021-03-06 18:36:55 C 09 23 29.59 -07 03 02.6 V K83
2021-03-06 18:40:30 C 09 23 26.02 -07 03 07.5 q 168
2021-03-06 18:44:40 C 09 23 28.06 -07 02 47.3 V G17
2021-03-06 18:46:45 C 09 23 27.65 -07 02 42.7 V G17
2021-03-06 18:48:48 C 09 23 27.26 -07 02 39.0 V G17
2021-03-06 18:52:30 C 09 23 23.70 -07 02 43.4 q 168
2021-03-06 19:00:30 C 09 23 22.14 -07 02 27.3 q 168
2021-03-06 19:41:09 C 09 23 16.74 -07 01 00.4 V 246
2021-03-06 19:41:52 C 09 23 16.60 -07 00 59.1 V 246
2021-03-06 19:42:06 C 09 23 16.56 -07 00 58.6 V 246
2021-03-06 19:42:21 C 09 23 16.51 -07 00 58.1 V 246
2021-03-06 19:42:38 C 09 23 16.45 -07 00 57.7 V 246
2021-03-06 19:42:59 C 09 23 16.39 -07 00 56.9 V 246
2021-03-06 19:49:59 C 09 23 14.61 -07 00 40.8 V L54
2021-03-06 20:10:58 C 09 23 11.26 -07 00 03.0 V B72
2021-03-06 20:12:59 C 09 23 10.86 -06 59 58.5 V B72
2021-03-06 20:13:08 C 09 23 10.90 -06 59 57.1 q L47
2021-03-06 20:15:01 C 09 23 10.45 -06 59 54.6 V B72
2021-03-06 20:17:02 C 09 23 10.09 -06 59 50.7 V B72
2021-03-06 20:19:05 C 09 23 09.67 -06 59 46.6 V B72
2021-03-06 20:21:07 C 09 23 09.27 -06 59 42.6 V B72
2021-03-06 20:23:09 C 09 23 08.86 -06 59 38.4 V B72
2021-03-06 20:25:09 C 09 23 08.48 -06 59 34.6 V B72
2021-03-06 20:25:47 C 09 23 08.22 -06 59 27.5 q L47
2021-03-06 20:27:10 C 09 23 08.08 -06 59 30.6 V B72
2021-03-06 20:29:12 C 09 23 07.69 -06 59 26.5 V B72
2021-03-06 20:30:32 C 09 23 06.70 -06 59 22.5 q 056
2021-03-06 20:32:25 C 09 23 07.02 -06 59 19.6 V B72
2021-03-06 20:32:26 C 09 23 07.04 -06 59 20.0 V B72
2021-03-06 20:34:27 C 09 23 06.69 -06 59 16.2 V B72
2021-03-06 20:35:46 C 09 23 05.73 -06 59 12.3 q 056
2021-03-06 20:36:29 C 09 23 06.29 -06 59 12.2 V B72
2021-03-06 20:38:30 C 09 23 05.87 -06 59 08.2 V B72
2021-03-06 20:41:02 C 09 23 04.69 -06 59 02.0 q 056
2021-03-06 20:45:44 C 09 23 04.36 -06 58 53.4 V K74
2021-03-06 20:46:16 C 09 23 03.69 -06 58 51.7 q 056
2021-03-06 20:47:46 C 09 23 03.24 -06 58 46.0 V L54
2021-03-06 20:49:05 C 09 23 03.69 -06 58 46.6 V K74
2021-03-06 20:51:31 C 09 23 02.64 -06 58 41.3 q 056
2021-03-06 20:52:26 C 09 23 03.05 -06 58 40.0 V K74
2021-03-06 20:55:45 C 09 23 02.42 -06 58 33.4 V K74
2021-03-06 20:59:04 C 09 23 01.74 -06 58 26.7 V K74
2021-03-06 21:34:43 C 09 22 54.51 -06 57 12.9 q L47
2021-03-06 21:35:58 C 09 22 54.18 -06 57 07.9 q L47
2021-03-06 21:37:16 C 09 22 54.09 -06 57 07.5 q L47
2021-03-06 21:38:26 C 09 22 53.73 -06 57 03.5 q L47
2021-03-06 21:39:33 C 09 22 53.58 -06 57 02.9 q L47
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)