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
2021-02-21 14:46:05 C 10 23 36.34 -15 47 12.5 q Q21
2021-02-21 14:50:36 C 10 23 35.37 -15 47 06.9 q Q21
2021-02-21 14:55:07 C 10 23 34.47 -15 47 01.6 q Q21
2021-02-21 20:38:35 C 10 22 33.18 -15 40 04.2 L28
2021-02-21 20:40:43 C 10 22 32.77 -15 40 01.8 L28
2021-02-21 20:41:47 C 10 22 32.55 -15 40 00.5 L28
2021-02-21 20:47:06 C 10 22 31.52 -15 39 54.4 L28
2021-02-21 20:48:10 C 10 22 31.27 -15 39 53.1 L28
2021-02-21 20:50:19 C 10 22 30.85 -15 39 50.4 L28
2021-02-21 20:54:35 C 10 22 29.99 -15 39 45.5 L28
2021-02-21 20:56:43 C 10 22 29.55 -15 39 42.8 L28
2021-02-21 20:58:50 C 10 22 29.14 -15 39 40.4 L28
2021-02-21 21:00:58 C 10 22 28.73 -15 39 37.7 L28
2021-02-21 21:02:02 C 10 22 28.53 -15 39 36.6 L28
2021-02-21 21:03:06 C 10 22 28.32 -15 39 35.4 L28
2021-02-21 21:04:11 C 10 22 28.07 -15 39 34.0 L28
2021-02-21 21:04:56 C 10 22 27.74 -15 39 40.1 V G34
2021-02-21 21:05:15 C 10 22 27.85 -15 39 32.8 L28
2021-02-21 21:07:17 C 10 22 27.28 -15 39 37.0 V G34
2021-02-21 21:08:27 C 10 22 27.21 -15 39 29.0 L28
2021-02-21 21:09:38 C 10 22 26.83 -15 39 34.1 V G34
2021-02-21 21:12:32 C 10 22 26.60 -15 39 26.4 V L39
2021-02-21 21:14:50 C 10 22 25.94 -15 39 21.6 L28
2021-02-21 21:16:09 C 10 22 25.89 -15 39 21.9 V L39
2021-02-21 21:16:58 C 10 22 25.49 -15 39 19.2 L28
2021-02-21 21:18:02 C 10 22 25.29 -15 39 17.7 L28
2021-02-21 21:18:18 C 10 22 25.11 -15 39 24.0 V G34
2021-02-21 21:19:47 C 10 22 25.15 -15 39 17.5 V L39
2021-02-21 21:20:39 C 10 22 24.59 -15 39 20.5 V G34
2021-02-21 21:21:15 C 10 22 24.67 -15 39 14.2 L28
2021-02-21 21:23:17 C 10 22 24.48 -15 39 13.5 V L39
2021-02-21 21:24:27 C 10 22 24.01 -15 39 10.6 L28
2021-02-21 21:25:31 C 10 22 23.81 -15 39 09.1 L28
2021-02-21 21:26:34 C 10 22 23.56 -15 39 07.8 L28
2021-02-21 21:28:42 C 10 22 23.17 -15 39 05.5 L28
2021-02-21 21:30:50 C 10 22 22.75 -15 39 02.5 L28
2021-02-21 21:31:45 C 10 22 22.73 -15 39 06.8 V B72
2021-02-21 21:32:49 C 10 22 22.53 -15 39 05.5 V B72
2021-02-21 21:33:50 C 10 22 22.33 -15 39 04.4 V B72
2021-02-21 21:34:03 C 10 22 22.08 -15 38 58.8 L28
2021-02-21 21:34:52 C 10 22 22.17 -15 39 03.2 V B72
2021-02-21 21:35:07 C 10 22 21.87 -15 38 57.8 L28
2021-02-21 21:35:54 C 10 22 21.93 -15 39 02.2 V B72
2021-02-21 21:36:11 C 10 22 21.66 -15 38 56.7 L28
2021-02-21 21:37:15 C 10 22 21.46 -15 38 55.0 L28
2021-02-21 21:39:23 C 10 22 20.99 -15 38 52.5 L28
2021-02-21 21:43:38 C 10 22 20.14 -15 38 47.6 L28
2021-02-21 21:45:46 C 10 22 19.72 -15 38 45.1 L28
2021-02-21 21:46:50 C 10 22 19.50 -15 38 43.8 L28
2021-02-21 21:47:55 C 10 22 19.30 -15 38 42.4 L28
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)