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
2021-02-12 09:57:23 C 11 00 03.50 -18 50 13.7 V T05
2021-02-12 10:05:18 C 11 00 02.25 -18 50 10.2 V T05
2021-02-12 10:41:26 C 10 59 56.54 -18 49 54.2 V T05
2021-02-12 21:10:28 C 10 58 26.46 -18 44 48.9 q M47
2021-02-12 21:16:51 C 10 58 25.43 -18 44 44.2 q M47
2021-02-12 21:21:28 C 10 58 24.55 -18 44 41.7 q M47
2021-02-12 21:28:17 C 10 58 23.29 -18 44 39.7 q M47
2021-02-12 21:32:56 C 10 58 22.59 -18 44 36.2 q M47
2021-02-12 21:38:47 C 10 58 21.75 -18 44 33.2 q M47
2021-02-12 21:43:31 C 10 58 20.94 -18 44 30.9 q M47
2021-02-13 00:08:52 C 10 57 59.55 -18 43 29.5 V 073
2021-02-13 00:30:43 C 10 57 56.08 -18 43 17.3 V 073
2021-02-13 00:52:35 C 10 57 52.66 -18 43 05.9 V 073
2021-02-13 01:00:26 C 10 57 53.065 -18 42 58.32 V Z84
2021-02-13 01:01:29 C 10 57 52.70 -18 43 05.4 V Z80
2021-02-13 01:06:29 C 10 57 51.83 -18 43 02.6 V Z80
2021-02-13 01:11:28 C 10 57 51.12 -18 43 00.2 V Z80
2021-02-13 01:16:29 C 10 57 50.32 -18 42 57.3 V Z80
2021-02-13 01:47:17 C 10 57 45.538 -18 42 34.03 V Z84
2021-02-13 02:34:08 C 10 57 38.014 -18 42 08.99 V Z84
2021-02-13 02:56:54 C 10 57 37.82 -18 40 43.6 q 834
2021-02-13 03:21:00 C 10 57 30.513 -18 41 43.05 V Z84
2021-02-13 04:02:14 C 10 57 27.38 -18 40 10.7 q 834
2021-02-13 04:06:55 C 10 57 23.218 -18 41 16.99 V Z84
2021-02-13 21:14:43 C 10 54 53.64 -18 31 50.1 V 186
2021-02-13 21:19:54 C 10 54 52.81 -18 31 46.9 V 186
2021-02-13 21:24:58 C 10 54 51.96 -18 31 44.0 V 186
2021-02-13 21:30:13 C 10 54 51.08 -18 31 41.2 V 186
2021-02-14 11:48:40 C 10 52 41.72 -18 22 46.5 V T08
2021-02-14 12:38:56 C 10 52 33.07 -18 22 14.2 V T08
2021-02-14 12:43:34 C 10 52 32.28 -18 22 11.1 V T08
2021-02-14 12:53:31 C 10 52 30.57 -18 22 04.5 V T08
2021-02-14 13:29:14 C 10 52 28.38 -18 20 45.6 V Q62
2021-02-14 13:34:14 C 10 52 27.53 -18 20 42.6 V Q62
2021-02-14 13:37:58 C 10 52 26.92 -18 20 40.4 V Q62
2021-02-14 18:38:07 C 10 51 42.01 -18 18 24.6 V M44
2021-02-14 18:47:50 C 10 51 40.31 -18 18 18.1 V M46
2021-02-14 18:53:52 C 10 51 39.36 -18 18 15.3 V M46
2021-02-14 18:59:17 C 10 51 38.48 -18 18 11.2 V M44
2021-02-14 18:59:54 C 10 51 38.24 -18 18 11.6 V M46
2021-02-14 19:05:56 C 10 51 37.28 -18 18 08.0 V M46
2021-02-14 19:11:59 C 10 51 36.23 -18 18 04.3 V M46
2021-02-14 19:16:35 C 10 51 35.55 -18 18 00.7 V M44
2021-02-14 19:21:47 C 10 51 32.99 -18 18 13.8 N42
2021-02-14 19:24:04 C 10 51 32.50 -18 18 11.9 N42
2021-02-14 19:26:22 C 10 51 32.13 -18 18 10.6 N42
2021-02-14 19:28:39 C 10 51 31.76 -18 18 09.2 N42
2021-02-14 19:30:57 C 10 51 31.43 -18 18 08.0 N42
2021-02-14 19:33:14 C 10 51 30.98 -18 18 06.3 N42
2021-02-14 19:35:30 C 10 51 30.57 -18 18 04.6 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)