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
2020-02-20 20:04:20 C 03 29 19.61 +12 25 31.3 V 511
2020-02-20 20:09:23 C 03 29 20.41 +12 25 34.6 V 511
2020-02-20 20:14:26 C 03 29 21.25 +12 25 38.4 V 511
2020-02-22 01:11:03 C 03 34 07.48 +12 46 18.2 V W34
2020-02-22 01:25:07 C 03 34 09.74 +12 46 28.9 V W34
2020-02-22 01:39:20 C 03 34 11.99 +12 46 38.7 V W34
2020-02-22 18:46:28 C 03 37 00.66 +12 58 33.6 U 511
2020-02-22 18:51:31 C 03 37 01.45 +12 58 34.8 U 511
2020-02-22 18:56:33 C 03 37 02.31 +12 58 39.9 U 511
2020-02-22 19:01:37 C 03 37 03.10 +12 58 42.9 U 511
2020-02-22 19:06:39 C 03 37 03.97 +12 58 46.8 U 511
2020-02-22 19:11:42 C 03 37 04.74 +12 58 50.1 U 511
2020-02-22 19:16:45 C 03 37 05.51 +12 58 53.6 U 511
2020-02-22 19:21:48 C 03 37 06.31 +12 58 57.0 U 511
2020-02-22 19:26:50 C 03 37 07.15 +12 59 00.4 U 511
2020-02-22 19:31:54 C 03 37 07.96 +12 59 04.1 U 511
2020-06-08 04:03:43 C 09 35 11.10 +14 38 52.8 V G96
2020-06-08 04:15:55 C 09 35 12.72 +14 38 48.3 V G96
2020-06-08 04:21:59 C 09 35 13.54 +14 38 45.1 V G96
2020-10-31 04:11:15 C 11 08 32.60 -00 13 11.5 V 204
2020-10-31 04:31:17 C 11 08 31.56 -00 13 17.3 V 204
2020-11-15 03:51:35 C 11 03 32.58 -02 43 05.9 V 204
2020-11-15 04:05:42 C 11 03 32.66 -02 43 12.8 V 204
2020-11-20 10:52:19 C 11 05 48.44 -03 50 25.8 q H36
2020-11-20 11:12:01 C 11 05 48.76 -03 50 36.7 q H36
2020-11-20 11:51:08 C 11 05 49.43 -03 50 58.8 q H36
2020-11-30 03:23:56 C 11 12 48.27 -06 04 44.6 V 094
2020-11-30 03:30:13 C 11 12 48.45 -06 04 48.4 V 094
2020-11-30 03:36:20 C 11 12 48.61 -06 04 52.0 V 094
2020-11-30 03:42:27 C 11 12 48.79 -06 04 55.6 V 094
2020-11-30 04:21:11 C 11 12 50.57 -06 05 19.3 V 204
2020-11-30 04:34:29 C 11 12 50.97 -06 05 27.2 V 204
2020-11-30 04:47:47 C 11 12 51.36 -06 05 35.4 V 204
2020-12-04 03:22:49 C 11 16 21.82 -07 03 08.4 V 094
2020-12-04 03:27:56 C 11 16 21.99 -07 03 11.4 V 094
2020-12-04 03:33:02 C 11 16 22.18 -07 03 14.8 V 094
2020-12-04 03:38:07 C 11 16 22.31 -07 03 17.7 V 094
2020-12-04 03:43:14 C 11 16 22.48 -07 03 20.7 V 094
2020-12-04 03:48:19 C 11 16 22.66 -07 03 25.1 V 094
2020-12-04 03:53:26 C 11 16 22.87 -07 03 27.0 V 094
2020-12-04 10:41:43 C 11 16 39.71 -07 07 33.3 V 703
2020-12-04 10:49:25 C 11 16 39.97 -07 07 37.8 V 703
2020-12-04 10:57:07 C 11 16 40.19 -07 07 43.2 V 703
2020-12-04 11:04:50 C 11 16 40.30 -07 07 47.1 V 703
2020-12-07 13:56:31 C 11 19 36.24 -07 54 10.8 V T05
2020-12-07 14:01:09 C 11 19 36.39 -07 54 13.4 V T05
2020-12-07 14:10:26 C 11 19 36.72 -07 54 19.3 V T05
2020-12-07 14:29:03 C 11 19 37.27 -07 54 31.1 V T05
2020-12-08 03:36:00 C 11 20 07.51 -08 02 54.2 V 094
2020-12-08 03:43:10 C 11 20 07.72 -08 02 58.8 V 094
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)