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
2005-01-14 21:07:48 C 03 10 22.59 -07 51 01.5 r 176
2005-01-14 21:09:05 C 03 10 22.81 -07 50 58.6 r 176
2005-01-14 21:10:21 C 03 10 23.05 -07 50 56.2 r 176
2005-01-14 21:11:38 C 03 10 23.28 -07 50 53.2 r 176
2005-01-14 21:12:54 C 03 10 23.50 -07 50 50.6 r 176
2005-01-14 21:30:14 C 03 10 26.46 -07 50 17.4 c 587
2005-01-14 21:32:49 C 03 10 26.91 -07 50 12.2 c 587
2005-01-14 21:35:26 C 03 10 27.38 -07 50 06.3 c 587
2005-01-15 02:56:51 C 03 11 28.83 -07 38 48.9 r H36
2005-01-15 03:02:52 C 03 11 29.86 -07 38 36.2 r H36
2005-01-15 03:08:53 C 03 11 30.89 -07 38 23.7 r H36
2005-01-15 03:21:50 C 03 11 34.46 -07 37 53.4 c 670
2005-01-15 03:51:59 C 03 11 39.66 -07 36 50.0 c 670
2005-01-15 04:03:58 C 03 11 41.73 -07 36 25.4 c 670
2005-01-15 18:05:13 C 03 14 18.32 -07 07 35.8 c 246
2005-01-15 18:06:23 C 03 14 18.52 -07 07 33.6 c 246
2005-01-15 18:07:12 C 03 14 18.66 -07 07 31.9 c 246
2005-01-15 18:08:04 C 03 14 18.81 -07 07 30.3 c 246
2005-01-15 18:09:07 C 03 14 18.98 -07 07 28.1 c 246
2005-01-15 18:10:11 C 03 14 19.16 -07 07 25.8 c 246
2005-01-15 18:16:23 C 03 14 20.47 -07 07 12.8 c A62
2005-01-15 18:17:12 C 03 14 20.60 -07 07 11.3 c A62
2005-01-15 18:18:01 C 03 14 20.74 -07 07 09.4 c A62
2005-01-15 18:18:51 C 03 14 20.90 -07 07 07.5 c A62
2005-01-15 18:19:41 C 03 14 21.05 -07 07 05.8 c A62
2005-01-15 18:20:31 C 03 14 21.18 -07 07 04.2 c A62
2005-01-15 18:21:20 C 03 14 21.31 -07 07 02.7 c A62
2005-01-15 18:22:09 C 03 14 21.46 -07 07 00.7 c A62
2005-01-15 18:23:29 C 03 14 21.68 -07 06 58.1 c A62
2005-01-15 18:24:48 C 03 14 21.91 -07 06 55.4 c A62
2005-01-15 18:26:08 C 03 14 22.15 -07 06 52.6 c A62
2005-01-15 18:26:57 C 03 14 22.27 -07 06 50.9 c A62
2005-01-15 18:27:45 C 03 14 22.40 -07 06 49.9 c A62
2005-01-15 18:28:35 C 03 14 22.56 -07 06 47.9 c A62
2005-01-15 18:29:24 C 03 14 22.70 -07 06 46.1 c A62
2005-01-15 18:30:13 C 03 14 22.85 -07 06 44.6 c A62
2005-01-15 18:31:02 C 03 14 22.96 -07 06 43.1 c A62
2005-01-15 18:31:52 C 03 14 23.11 -07 06 41.5 c A62
2005-01-15 18:34:31 C 03 14 23.56 -07 06 35.5 c A62
2005-01-15 18:35:25 C 03 14 23.72 -07 06 33.6 c A62
2005-01-15 18:41:17 C 03 14 24.74 -07 06 21.9 c A62
2005-01-15 18:41:18 C 03 14 24.76 -07 06 22.3 o 198
2005-01-15 18:42:06 C 03 14 24.88 -07 06 20.2 c A62
2005-01-15 18:42:53 C 03 14 25.03 -07 06 18.7 c A62
2005-01-15 18:43:42 C 03 14 25.15 -07 06 17.2 c A62
2005-01-15 18:44:29 C 03 14 25.28 -07 06 15.5 c A62
2005-01-15 18:45:18 C 03 14 25.42 -07 06 14.1 c A62
2005-01-15 18:46:05 C 03 14 25.55 -07 06 12.3 c A62
2005-01-15 18:46:33 C 03 14 25.66 -07 06 11.4 o 198
2005-01-15 18:46:54 C 03 14 25.69 -07 06 10.6 c A62
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)