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
2021-02-06 22:51:36 C 11 16 22.17 -19 28 44.8 V 221
2021-02-06 22:53:22 C 11 16 21.96 -19 28 44.6 V 221
2021-02-06 22:55:05 C 11 16 21.75 -19 28 44.7 V 221
2021-02-06 22:56:51 C 11 16 21.52 -19 28 44.4 V 221
2021-02-06 22:58:35 C 11 16 21.32 -19 28 44.4 V 221
2021-02-06 23:00:21 C 11 16 21.11 -19 28 44.1 V 221
2021-02-06 23:02:06 C 11 16 20.89 -19 28 43.8 V 221
2021-02-06 23:03:51 C 11 16 20.67 -19 28 43.7 V 221
2021-02-06 23:05:34 C 11 16 20.47 -19 28 43.5 V 221
2021-02-06 23:07:18 C 11 16 20.24 -19 28 43.3 V 221
2021-02-06 23:08:59 C 11 16 20.05 -19 28 43.3 V 221
2021-02-06 23:10:39 C 11 16 19.83 -19 28 43.0 V 221
2021-02-06 23:12:23 C 11 16 19.63 -19 28 42.7 V 221
2021-02-06 23:14:03 C 11 16 19.42 -19 28 42.7 V 221
2021-02-06 23:15:51 C 11 16 19.19 -19 28 42.4 V 221
2021-02-06 23:17:36 C 11 16 18.99 -19 28 42.3 V 221
2021-02-06 23:19:15 C 11 16 18.79 -19 28 42.2 V 221
2021-02-06 23:20:55 C 11 16 18.58 -19 28 41.9 V 221
2021-02-06 23:22:39 C 11 16 18.35 -19 28 41.8 V 221
2021-02-06 23:24:20 C 11 16 18.17 -19 28 41.6 V 221
2021-02-06 23:26:00 C 11 16 17.96 -19 28 41.4 V 221
2021-02-06 23:27:43 C 11 16 17.74 -19 28 41.2 V 221
2021-02-06 23:39:33 C 11 16 16.27 -19 28 39.7 V 221
2021-02-06 23:41:14 C 11 16 16.07 -19 28 39.6 V 221
2021-02-06 23:42:54 C 11 16 15.86 -19 28 39.6 V 221
2021-02-06 23:44:33 C 11 16 15.66 -19 28 39.4 V 221
2021-02-07 08:23:50 C 11 15 18.71 -19 28 12.8 V 703
2021-02-07 08:31:34 C 11 15 17.75 -19 28 11.4 V 703
2021-02-07 08:39:17 C 11 15 16.82 -19 28 10.0 V 703
2021-02-07 08:47:00 C 11 15 15.81 -19 28 09.2 V 703
2021-02-07 10:26:09 C 11 15 03.26 -19 27 53.1 o 290
2021-02-07 10:27:07 C 11 15 03.15 -19 27 52.9 o 290
2021-02-07 10:28:05 C 11 15 03.02 -19 27 52.8 o 290
2021-02-07 10:29:03 C 11 15 02.90 -19 27 52.6 o 290
2021-02-07 10:30:01 C 11 15 02.78 -19 27 52.4 o 290
2021-02-07 10:30:59 C 11 15 02.67 -19 27 52.3 o 290
2021-02-07 10:49:48 C 11 15 00.30 -19 27 48.6 o 290
2021-02-07 10:50:46 C 11 15 00.18 -19 27 48.5 o 290
2021-02-07 10:51:44 C 11 15 00.05 -19 27 48.4 o 290
2021-02-07 10:52:43 C 11 14 59.93 -19 27 48.3 o 290
2021-02-07 10:53:41 C 11 14 59.81 -19 27 48.0 o 290
2021-02-07 10:54:40 C 11 14 59.69 -19 27 47.7 o 290
2021-02-07 12:34:17 C 11 14 49.84 -19 27 22.8 V T08
2021-02-07 12:38:56 C 11 14 49.24 -19 27 21.8 V T08
2021-02-07 12:47:24 C 11 14 48.16 -19 27 20.5 V T08
2021-02-07 13:06:13 C 11 14 45.802 -19 27 17.90 U F51
2021-02-07 13:06:41 C 11 14 45.68 -19 27 16.9 V T08
2021-02-07 13:35:54 C 11 14 41.973 -19 27 12.43 U F51
2021-02-07 13:50:49 C 11 14 40.065 -19 27 09.46 U F51
2021-02-07 15:50:25 C 11 14 28.33 -19 25 59.2 V Q62
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)