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
2021-03-04 20:04:05 S 09 32 23.688 -08 48 46.48 V C57
2021-03-04 20:04:05 s 1 -194626.08 2 +178948.88 3830.0 C57
2021-03-04 20:05:27 C 09 32 02.36 -08 34 08.3 V A84
2021-03-04 20:07:16 C 09 32 01.99 -08 34 04.9 V A84
2021-03-04 20:09:06 C 09 32 01.61 -08 34 01.3 V A84
2021-03-04 20:10:56 C 09 32 01.24 -08 33 57.9 V A84
2021-03-04 20:12:45 C 09 32 00.87 -08 33 54.3 V A84
2021-03-04 20:14:05 S 09 32 21.269 -08 48 26.75 V C57
2021-03-04 20:14:05 s 1 -194661.67 5 +178271.89 1290.0 C57
2021-03-04 20:14:34 C 09 32 00.49 -08 33 50.8 V A84
2021-03-04 20:16:25 C 09 32 00.11 -08 33 47.3 V A84
2021-03-04 20:24:05 S 09 32 18.910 -08 48 07.09 V C57
2021-03-04 20:24:05 s 1 -194695.79 1 +177593.56 6020.0 C57
2021-03-04 20:34:05 S 09 32 16.500 -08 47 46.54 V C57
2021-03-04 20:34:05 s 1 -194728.42 4 +176913.87 8020.0 C57
2021-03-04 20:44:05 S 09 32 14.167 -08 47 25.62 V C57
2021-03-04 20:44:05 s 1 -194759.56 5 +176232.84 7260.0 C57
2021-03-04 20:53:47 C 09 31 51.89 -08 32 42.2 V C40
2021-03-04 20:54:05 S 09 32 11.738 -08 47 06.00 V C57
2021-03-04 20:54:05 s 1 -194789.20 7 +175550.45 3730.0 C57
2021-03-04 20:55:20 C 09 31 51.58 -08 32 39.4 V C40
2021-03-04 20:56:53 C 09 31 51.26 -08 32 36.2 V C40
2021-03-04 21:04:05 S 09 32 09.398 -08 46 46.34 V C57
2021-03-04 21:04:05 s 1 -194817.34 2 +174866.70 7420.0 C57
2021-03-04 21:06:08 C 09 31 49.39 -08 32 18.5 V C40
2021-03-04 21:07:36 C 09 31 49.92 -08 32 15.4 V 073
2021-03-04 21:07:39 C 09 31 49.08 -08 32 15.3 V C40
2021-03-04 21:08:17 C 09 31 49.97 -08 32 15.2 V L54
2021-03-04 21:12:17 C 09 31 48.13 -08 32 06.4 V C40
2021-03-04 21:13:51 C 09 31 47.82 -08 32 03.5 V C40
2021-03-04 21:14:05 S 09 32 07.034 -08 46 26.04 V C57
2021-03-04 21:14:05 s 1 -194843.96 4 +174181.60 8310.0 C57
2021-03-04 21:15:22 C 09 31 47.52 -08 32 00.5 V C40
2021-03-04 21:19:08 C 09 31 47.59 -08 31 53.2 V 073
2021-03-04 21:23:44 C 09 31 46.84 -08 31 45.2 V L54
2021-03-04 21:24:05 S 09 32 04.663 -08 46 04.69 V C57
2021-03-04 21:24:05 s 1 -194869.06 4 +173495.15 6390.0 C57
2021-03-04 21:31:42 C 09 31 45.01 -08 31 28.9 V 073
2021-03-04 21:34:05 S 09 32 02.306 -08 45 45.32 V C57
2021-03-04 21:34:05 s 1 -194892.63 5 +172807.33 1650.0 C57
2021-03-04 21:35:01 C 09 31 44.55 -08 31 23.3 V L54
2021-03-04 21:39:10 C 09 31 43.72 -08 31 15.0 V L54
2021-03-04 21:44:05 S 09 31 59.947 -08 45 25.81 V C57
2021-03-04 21:44:05 s 1 -194914.66 8 +172118.15 4050.0 C57
2021-03-04 21:54:05 S 09 31 57.574 -08 45 05.29 V C57
2021-03-04 21:54:05 s 1 -194935.15 7 +171427.62 3610.0 C57
2021-03-04 21:54:37 C 09 31 40.58 -08 30 45.5 V L54
2021-03-04 22:04:05 S 09 31 55.183 -08 44 44.34 V C57
2021-03-04 22:04:05 s 1 -194954.09 3 +170735.72 290.0 C57
2021-03-04 22:10:03 C 09 31 37.44 -08 30 15.4 V L54
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)