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
2004-12-30 17:10:26 C 01 34 24.80 -23 51 26.2 c 434
2004-12-30 17:12:34 C 01 34 25.66 -23 51 20.0 c 587
2004-12-30 17:13:16 C 01 34 25.66 -23 51 18.5 c 434
2004-12-30 17:15:12 C 01 34 26.49 -23 51 11.6 c 587
2004-12-30 17:15:56 C 01 34 26.63 -23 51 09.6 c 434
2004-12-30 17:20:24 C 01 34 28.32 -23 50 56.4 c 587
2004-12-30 17:25:47 C 01 34 30.23 -23 50 39.5 c 587
2004-12-30 17:28:22 C 01 34 31.20 -23 50 32.6 c 587
2004-12-30 20:13:20 C 01 35 29.14 -23 42 03.5 r 176
2004-12-30 20:14:07 C 01 35 29.44 -23 42 01.0 r 176
2004-12-30 20:14:53 C 01 35 29.71 -23 41 58.7 r 176
2004-12-30 20:15:39 C 01 35 29.97 -23 41 56.3 r 176
2004-12-30 20:16:26 C 01 35 30.25 -23 41 54.0 r 176
2004-12-31 01:05:08 C 01 37 13.30 -23 25 54.5 r I77
2004-12-31 01:05:41 C 01 37 13.46 -23 25 53.1 r I77
2004-12-31 01:06:15 C 01 37 13.76 -23 25 50.9 r I77
2004-12-31 01:19:15 C 01 37 23.60 -23 26 24.7 r 715
2004-12-31 01:35:53 C 01 37 29.28 -23 25 34.1 r 715
2004-12-31 01:44:13 C 01 37 32.11 -23 25 09.0 r 715
2004-12-31 01:48:27 C 01 37 32.66 -23 25 01.2 r 734
2004-12-31 01:51:47 C 01 37 33.80 -23 24 50.2 r 734
2004-12-31 01:52:52 C 01 37 35.06 -23 24 42.5 r 715
2004-12-31 01:55:05 C 01 37 34.91 -23 24 40.2 r 734
2004-12-31 11:17:38 C 01 40 54.73 -22 54 32.7 r 423
2004-12-31 11:28:38 C 01 40 58.45 -22 53 58.7 r 423
2004-12-31 11:41:38 C 01 41 02.85 -22 53 17.9 r 423
2004-12-31 11:51:38 C 01 41 06.25 -22 52 46.3 r 423
2004-12-31 17:48:34 C 01 43 16.29 -22 36 20.4 c 104
2004-12-31 17:52:23 C 01 43 17.59 -22 36 08.4 c 104
2004-12-31 17:55:37 C 01 43 18.68 -22 35 58.6 c 104
2005-01-01 04:13:22 C 01 46 50.00 -22 04 36.4 o H06
2005-01-01 04:23:53 C 01 46 53.44 -22 04 04.0 o H06
2005-01-01 04:39:17 C 01 46 58.44 -22 03 16.5 o H06
2005-01-01 17:04:44 C 01 51 15.59 -21 26 04.8 o 185
2005-01-01 17:14:00 C 01 51 18.53 -21 25 37.9 o 185
2005-01-01 17:44:57 C 01 51 28.22 -21 24 02.7 c 434
2005-01-01 17:48:24 C 01 51 29.34 -21 23 53.5 c 434
2005-01-01 17:51:13 C 01 51 30.09 -21 23 46.3 c 434
2005-01-01 17:54:38 C 01 51 31.20 -21 23 35.0 c 434
2005-01-01 18:06:36 C 01 51 35.92 -21 22 54.4 c 952
2005-01-01 18:17:28 C 01 51 39.38 -21 22 22.0 c 952
2005-01-01 18:33:49 C 01 51 44.49 -21 21 33.2 c 952
2005-01-01 18:47:49 C 01 51 48.05 -21 20 55.3 r A30
2005-01-01 18:49:30 C 01 51 48.57 -21 20 50.4 r A30
2005-01-01 19:01:02 C 01 51 53.02 -21 20 11.9 c 952
2005-01-01 19:02:09 C 01 51 52.55 -21 20 12.6 r A30
2005-01-01 19:08:33 C 01 51 54.58 -21 19 53.6 r A30
2005-01-01 19:17:23 C 01 51 58.15 -21 19 22.8 c 952
2005-01-01 19:45:18 C 01 52 06.94 -21 17 59.1 r 941
2005-01-01 19:47:34 C 01 52 07.66 -21 17 52.2 r 941
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)