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
2021-03-03 20:54:05 S 09 37 53.760 -09 33 59.22 V C57
2021-03-03 20:54:05 s 1 -178003.60 2 +260537.63 8740.0 C57
2021-03-03 20:56:04 C 09 36 23.69 -09 18 28.0 V C73
2021-03-03 21:00:00 C 09 36 22.94 -09 18 20.5 V C73
2021-03-03 21:03:57 C 09 36 22.13 -09 18 12.7 V C73
2021-03-03 21:04:05 S 09 37 51.343 -09 33 40.61 V C57
2021-03-03 21:04:05 s 1 -178190.78 9 +260035.23 1940.0 C57
2021-03-03 21:07:54 C 09 36 21.30 -09 18 05.7 V C73
2021-03-03 21:11:51 C 09 36 20.46 -09 17 58.3 V C73
2021-03-03 21:14:05 S 09 37 48.998 -09 33 22.36 V C57
2021-03-03 21:14:05 s 1 -178377.17 3 +259531.65 3710.0 C57
2021-03-03 21:15:47 C 09 36 19.64 -09 17 51.4 V C73
2021-03-03 21:19:44 C 09 36 18.82 -09 17 43.5 V C73
2021-03-03 21:23:41 C 09 36 18.02 -09 17 36.5 V C73
2021-03-03 21:24:05 S 09 37 46.608 -09 33 03.46 V C57
2021-03-03 21:24:05 s 1 -178562.74 9 +259026.91 4040.0 C57
2021-03-03 21:31:00 C 09 36 17.24 -09 17 17.8 q K73
2021-03-03 21:33:45 C 09 36 16.71 -09 17 13.3 q K73
2021-03-03 21:34:05 S 09 37 44.251 -09 32 43.58 V C57
2021-03-03 21:34:05 s 1 -178747.51 5 +258520.99 2920.0 C57
2021-03-03 21:36:29 C 09 36 16.09 -09 17 09.7 q K73
2021-03-03 21:37:27 C 09 36 15.58 -09 17 10.2 V L54
2021-03-03 21:39:14 C 09 36 15.63 -09 17 03.3 q K73
2021-03-03 21:42:00 C 09 36 15.01 -09 16 56.1 q K73
2021-03-03 21:44:05 S 09 37 41.849 -09 32 24.54 V C57
2021-03-03 21:44:05 s 1 -178931.46 6 +258013.90 350.0 C57
2021-03-03 21:44:45 C 09 36 14.45 -09 16 52.4 q K73
2021-03-03 21:47:28 C 09 36 13.88 -09 16 47.2 q K73
2021-03-03 21:54:05 S 09 37 39.458 -09 32 06.25 V C57
2021-03-03 21:54:05 s 1 -179114.60 1 +257505.63 6320.0 C57
2021-03-03 22:04:05 S 09 37 37.126 -09 31 47.78 V C57
2021-03-03 22:04:05 s 1 -179296.91 6 +256996.19 820.0 C57
2021-03-03 22:14:05 S 09 37 34.778 -09 31 28.38 V C57
2021-03-03 22:14:05 s 1 -179478.40 7 +256485.57 3840.0 C57
2021-03-03 22:24:05 S 09 37 32.443 -09 31 08.00 V C57
2021-03-03 22:24:05 s 1 -179659.07 2 +255973.77 5390.0 C57
2021-03-03 22:34:05 S 09 37 30.062 -09 30 49.57 V C57
2021-03-03 22:34:05 s 1 -179838.90 7 +255460.79 5460.0 C57
2021-03-03 22:44:05 S 09 37 27.710 -09 30 31.68 V C57
2021-03-03 22:44:05 s 1 -180017.90 8 +254946.63 4030.0 C57
2021-03-03 22:54:05 S 09 37 25.291 -09 30 12.67 V C57
2021-03-03 22:54:05 s 1 -180196.07 3 +254431.29 1110.0 C57
2021-03-03 23:04:05 S 09 37 22.932 -09 29 52.48 V C57
2021-03-03 23:04:05 s 1 -180373.39 9 +253914.76 6680.0 C57
2021-03-03 23:14:05 S 09 37 20.539 -09 29 32.89 V C57
2021-03-03 23:14:05 s 1 -180549.88 1 +253397.05 740.0 C57
2021-03-03 23:20:17 C 09 35 54.48 -09 13 54.4 V L54
2021-03-03 23:27:26 C 09 35 55.58 -09 13 25.8 t Z21
2021-03-03 23:31:58 C 09 35 54.63 -09 13 17.2 t Z21
2021-03-03 23:32:25 C 09 35 54.52 -09 13 16.5 t Z17
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)