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
2021-02-07 15:52:55 C 11 14 28.01 -19 25 58.8 V Q62
2021-02-07 15:56:38 C 11 14 27.54 -19 25 58.2 V Q62
2021-02-07 21:30:23 C 11 13 52.77 -19 24 58.2 V 221
2021-02-07 21:32:11 C 11 13 52.54 -19 24 58.0 V 221
2021-02-07 21:33:58 C 11 13 52.32 -19 24 57.9 V 221
2021-02-07 21:35:43 C 11 13 52.10 -19 24 57.7 V 221
2021-02-07 21:37:36 C 11 13 51.87 -19 24 57.4 V 221
2021-02-07 21:39:23 C 11 13 51.65 -19 24 57.1 V 221
2021-02-07 21:41:09 C 11 13 51.43 -19 24 56.9 V 221
2021-02-07 21:42:58 C 11 13 51.20 -19 24 56.6 V 221
2021-02-07 21:44:45 C 11 13 50.98 -19 24 56.4 V 221
2021-02-07 21:46:33 C 11 13 50.75 -19 24 56.2 V 221
2021-02-07 21:48:18 C 11 13 50.53 -19 24 56.0 V 221
2021-02-07 21:50:05 C 11 13 50.31 -19 24 55.8 V 221
2021-02-07 21:51:54 C 11 13 50.08 -19 24 55.5 V 221
2021-02-07 21:53:42 C 11 13 49.85 -19 24 55.3 V 221
2021-02-07 21:55:28 C 11 13 49.62 -19 24 55.0 V 221
2021-02-08 07:03:32 C 11 12 46.06 -19 23 57.9 o 691
2021-02-08 07:39:31 C 11 12 41.40 -19 23 51.7 o 691
2021-02-08 07:56:16 C 11 12 39.57 -19 23 49.4 q U71
2021-02-08 08:13:06 C 11 12 37.01 -19 23 45.4 o 691
2021-02-08 08:13:09 C 11 12 37.35 -19 23 46.0 q U71
2021-02-08 08:29:08 C 11 12 35.26 -19 23 42.9 q U71
2021-02-08 13:22:14 C 11 11 58.68 -19 22 28.9 V T05
2021-02-08 14:10:29 C 11 11 52.21 -19 22 16.5 V T05
2021-02-08 14:17:00 C 11 11 51.30 -19 22 14.4 V T05
2021-02-08 14:26:54 C 11 11 50.03 -19 22 12.0 V T05
2021-02-09 07:19:59 C 11 09 52.37 -19 18 06.6 o 691
2021-02-09 07:53:28 C 11 09 47.79 -19 17 58.8 o 691
2021-02-09 08:24:44 C 11 09 43.48 -19 17 50.9 o 691
2021-02-09 20:52:04 C 11 08 11.70 -19 14 18.8 V C40
2021-02-09 20:58:14 C 11 08 10.87 -19 14 17.1 V C40
2021-02-09 21:01:20 C 11 08 10.43 -19 14 16.2 V C40
2021-02-09 21:36:26 C 11 08 05.62 -19 14 06.7 V C40
2021-02-09 21:48:47 C 11 08 03.91 -19 14 03.0 V C40
2021-02-09 21:51:52 C 11 08 03.49 -19 14 02.3 V C40
2021-02-09 21:59:35 C 11 08 02.41 -19 14 00.2 V C40
2021-02-09 22:07:16 C 11 08 01.35 -19 13 57.8 V C40
2021-02-09 22:11:54 C 11 08 00.70 -19 13 56.6 V C40
2021-02-09 22:14:59 C 11 08 00.28 -19 13 55.6 V C40
2021-02-09 22:16:32 C 11 08 00.07 -19 13 55.0 V C40
2021-02-09 22:21:10 C 11 07 59.41 -19 13 53.8 V C40
2021-02-10 11:25:19 C 11 06 19.42 -19 09 19.4 V T08
2021-02-10 11:29:17 C 11 06 18.83 -19 09 18.1 V T08
2021-02-10 11:36:35 C 11 06 17.76 -19 09 15.8 V T08
2021-02-10 21:27:38 C 11 05 00.17 -19 06 04.5 q 168
2021-02-10 21:31:38 C 11 04 59.60 -19 06 03.5 q 168
2021-02-10 21:33:37 C 11 04 59.33 -19 06 03.1 q 168
2021-02-10 21:37:37 C 11 04 58.75 -19 06 01.0 q 168
2021-02-10 21:39:37 C 11 04 58.43 -19 06 00.8 q 168
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)