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
2004-12-25 03:00:44 C 00 37 38.48 -30 33 38.5 m 683
2004-12-25 03:04:17 C 00 37 40.07 -30 33 28.4 m 683
2004-12-25 03:07:00 C 00 37 41.29 -30 33 20.0 m 683
2004-12-25 03:13:40 C 00 37 44.26 -30 33 02.1 m 683
2004-12-25 03:19:08 C 00 37 46.83 -30 32 45.8 m 683
2004-12-25 04:25:13 C 00 38 16.55 -30 29 31.1 r 448
2004-12-25 04:28:25 C 00 38 18.02 -30 29 21.7 r 448
2004-12-25 04:32:17 C 00 38 19.78 -30 29 10.3 r 448
2004-12-26 00:01:55 C 00 47 32.86 -29 33 26.1 r H36
2004-12-26 00:06:38 C 00 47 34.97 -29 33 12.2 r H36
2004-12-26 00:25:57 C 00 47 43.38 -29 32 17.8 r H36
2004-12-26 00:37:48 C 00 47 48.57 -29 31 43.1 r H36
2004-12-26 00:55:06 C 00 47 56.21 -29 30 52.8 r H36
2004-12-26 01:06:55 C 00 48 01.35 -29 30 17.8 r H36
2004-12-26 01:09:56 C 00 48 03.52 -29 30 05.8 o H06
2004-12-26 01:13:34 C 00 48 05.27 -29 29 54.7 r 715
2004-12-26 01:16:42 C 00 48 06.48 -29 29 46.0 o H06
2004-12-26 01:17:58 C 00 48 07.01 -29 29 41.3 o H06
2004-12-26 01:18:08 C 00 48 06.18 -29 29 45.6 r H36
2004-12-26 01:19:17 C 00 48 07.74 -29 29 38.0 r 715
2004-12-26 01:20:01 C 00 48 07.97 -29 29 35.4 o H06
2004-12-26 01:22:03 C 00 48 08.82 -29 29 30.0 o H06
2004-12-26 01:23:07 C 00 48 09.27 -29 29 27.2 o H06
2004-12-26 01:24:56 C 00 48 10.20 -29 29 21.8 r 715
2004-12-26 01:30:31 C 00 48 12.62 -29 29 05.6 r 715
2004-12-26 01:38:13 C 00 48 15.83 -29 28 43.1 o H06
2004-12-26 01:50:15 C 00 48 21.63 -29 28 07.8 m 683
2004-12-26 01:53:30 C 00 48 23.03 -29 27 58.6 m 683
2004-12-26 01:54:09 C 00 48 22.72 -29 27 55.8 o H06
2004-12-26 01:57:59 C 00 48 24.90 -29 27 44.9 m 683
2004-12-26 02:02:51 C 00 48 27.09 -29 27 30.8 m 683
2004-12-26 02:03:40 C 00 48 26.89 -29 27 28.9 o H06
2004-12-26 02:05:37 C 00 48 28.26 -29 27 23.1 m 683
2004-12-26 02:09:10 C 00 48 29.90 -29 27 13.2 m 683
2004-12-26 02:10:43 C 00 48 29.87 -29 27 07.1 o H06
2004-12-26 02:11:50 C 00 48 30.98 -29 27 05.2 m 683
2004-12-26 02:14:08 C 00 48 31.38 -29 26 57.4 o H06
2004-12-26 02:14:59 C 00 48 31.77 -29 26 56.1 o H06
2004-12-26 02:16:38 C 00 48 33.07 -29 26 50.9 m 683
2004-12-26 02:17:28 C 00 48 32.89 -29 26 47.6 o H06
2004-12-26 02:19:19 C 00 48 34.19 -29 26 42.9 m 683
2004-12-26 02:21:55 C 00 48 35.47 -29 26 37.7 o 699
2004-12-26 02:22:22 C 00 48 35.60 -29 26 35.7 m 683
2004-12-26 02:22:36 C 00 48 35.72 -29 26 35.1 o 699
2004-12-26 02:23:15 C 00 48 36.05 -29 26 34.3 o 699
2004-12-26 02:23:54 C 00 48 36.28 -29 26 31.7 o 699
2004-12-26 02:25:02 C 00 48 36.66 -29 26 26.7 m 683
2004-12-26 02:27:57 C 00 48 37.94 -29 26 17.1 c 651
2004-12-26 02:28:07 C 00 48 38.05 -29 26 16.5 m 683
2004-12-26 02:30:02 C 00 48 38.84 -29 26 10.9 c 651
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)