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
2021-02-14 21:27:46 C 10 51 11.61 -18 16 50.7 N42
2021-02-14 21:30:04 C 10 51 11.19 -18 16 48.9 N42
2021-02-14 21:32:21 C 10 51 10.81 -18 16 47.3 N42
2021-02-14 21:34:38 C 10 51 10.42 -18 16 45.9 N42
2021-02-14 21:36:57 C 10 51 10.04 -18 16 44.3 N42
2021-02-14 21:59:30 C 10 51 06.24 -18 16 28.4 N42
2021-02-14 22:01:24 C 10 51 10.64 -18 16 18.5 V J37
2021-02-14 22:01:48 C 10 51 05.82 -18 16 26.9 N42
2021-02-14 22:04:05 C 10 51 05.46 -18 16 25.5 N42
2021-02-14 22:06:23 C 10 51 05.04 -18 16 23.7 N42
2021-02-14 22:08:12 C 10 51 09.52 -18 16 14.3 V J37
2021-02-14 22:08:40 C 10 51 04.65 -18 16 22.2 N42
2021-02-14 22:10:56 C 10 51 04.28 -18 16 20.6 N42
2021-02-14 22:13:14 C 10 51 03.90 -18 16 19.1 N42
2021-02-14 22:15:31 C 10 51 03.50 -18 16 17.5 N42
2021-02-14 22:17:48 C 10 51 03.62 -18 16 14.8 V 186
2021-02-14 22:17:49 C 10 51 03.15 -18 16 16.0 N42
2021-02-14 22:20:06 C 10 51 02.74 -18 16 14.3 N42
2021-02-14 22:22:23 C 10 51 02.34 -18 16 12.7 N42
2021-02-14 22:24:42 C 10 51 02.02 -18 16 11.3 N42
2021-02-14 22:26:59 C 10 51 01.62 -18 16 09.6 N42
2021-02-14 22:29:16 C 10 51 01.20 -18 16 07.8 N42
2021-02-14 22:31:34 C 10 51 00.82 -18 16 06.2 N42
2021-02-14 22:38:24 C 10 51 04.50 -18 15 56.3 V J37
2021-02-14 22:52:01 C 10 51 02.21 -18 15 47.3 V J37
2021-02-14 23:01:57 C 10 51 00.56 -18 15 41.4 V J37
2021-02-14 23:29:02 C 10 50 51.62 -18 15 25.0 V 186
2021-02-15 14:26:01 C 10 48 34.30 -18 05 07.7 q Q21
2021-02-15 14:32:04 C 10 48 33.27 -18 05 04.2 q Q21
2021-02-15 14:39:40 C 10 48 31.99 -18 04 59.0 q Q21
2021-02-15 17:47:46 C 10 48 02.71 -18 02 45.7 N42
2021-02-15 17:49:03 C 10 48 02.49 -18 02 44.9 N42
2021-02-15 17:50:21 C 10 48 02.29 -18 02 44.0 N42
2021-02-15 17:51:38 C 10 48 02.05 -18 02 43.1 N42
2021-02-15 17:52:55 C 10 48 01.82 -18 02 42.1 N42
2021-02-15 17:54:12 C 10 48 01.61 -18 02 41.3 N42
2021-02-15 17:55:30 C 10 48 01.39 -18 02 40.4 N42
2021-02-15 17:56:48 C 10 48 01.16 -18 02 39.6 N42
2021-02-15 17:59:22 C 10 48 00.71 -18 02 37.8 N42
2021-02-15 18:00:39 C 10 48 00.51 -18 02 37.0 N42
2021-02-15 18:01:57 C 10 48 00.27 -18 02 36.1 N42
2021-02-15 18:03:14 C 10 48 00.06 -18 02 35.2 N42
2021-02-15 18:04:32 C 10 47 59.83 -18 02 34.3 N42
2021-02-15 18:05:49 C 10 47 59.62 -18 02 33.4 N42
2021-02-15 18:07:06 C 10 47 59.39 -18 02 32.6 N42
2021-02-15 18:08:23 C 10 47 59.17 -18 02 31.5 N42
2021-02-15 18:09:41 C 10 47 58.91 -18 02 30.5 N42
2021-02-15 18:10:58 C 10 47 58.71 -18 02 29.7 N42
2021-02-15 18:12:16 C 10 47 58.47 -18 02 28.9 N42
2021-02-15 18:13:33 C 10 47 58.27 -18 02 28.1 N42
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)