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
2021-02-20 13:34:05 s 1 -194933.81 5 +106155.39 5920.0 C57
2021-02-20 13:44:05 S 10 28 27.497 -16 33 43.13 V C57
2021-02-20 13:44:05 s 1 -194772.82 5 +105354.19 4320.0 C57
2021-02-20 13:54:05 S 10 28 25.116 -16 33 29.74 V C57
2021-02-20 13:54:05 s 1 -194609.36 6 +104551.65 8070.0 C57
2021-02-20 14:04:05 S 10 28 22.810 -16 33 16.60 V C57
2021-02-20 14:04:05 s 1 -194443.42 2 +103747.77 7140.0 C57
2021-02-20 17:25:46 C 10 27 27.70 -16 10 44.6 V Q62
2021-02-20 17:28:24 C 10 27 27.21 -16 10 41.9 V Q62
2021-02-20 17:29:43 C 10 27 26.92 -16 10 40.1 V Q62
2021-02-20 17:32:21 C 10 27 26.45 -16 10 37.0 V Q62
2021-02-20 20:19:45 C 10 27 00.68 -16 08 52.8 c 095
2021-02-20 20:20:02 C 10 27 00.62 -16 08 52.1 c 095
2021-02-20 20:20:35 C 10 27 00.51 -16 08 52.2 c 095
2021-02-20 20:21:08 C 10 27 00.44 -16 08 51.2 c 095
2021-02-20 20:21:26 C 10 27 00.35 -16 08 51.3 c 095
2021-02-20 20:21:42 C 10 27 00.32 -16 08 50.6 c 095
2021-02-20 20:22:32 C 10 27 00.15 -16 08 49.9 c 095
2021-02-20 20:22:50 C 10 27 00.11 -16 08 49.5 c 095
2021-02-20 20:23:06 C 10 27 00.04 -16 08 49.6 c 095
2021-02-20 20:23:22 C 10 27 00.01 -16 08 48.9 c 095
2021-02-20 20:23:56 C 10 26 59.88 -16 08 48.2 c 095
2021-02-20 20:25:03 C 10 26 59.66 -16 08 47.2 c 095
2021-02-20 20:25:36 C 10 26 59.55 -16 08 46.1 c 095
2021-02-20 20:26:10 C 10 26 59.47 -16 08 45.2 c 095
2021-02-20 21:04:05 S 10 26 43.003 -16 23 50.28 V C57
2021-02-20 21:04:05 s 1 -185005.53 7 +68799.306 4920.0 C57
2021-02-20 21:54:05 S 10 26 30.946 -16 22 41.20 V C57
2021-02-20 21:54:05 s 1 -183525.04 8 +64489.533 9240.0 C57
2021-02-20 22:25:40 C 10 26 36.48 -16 06 30.1 V L54
2021-02-20 22:38:22 C 10 26 34.76 -16 06 18.4 V B72
2021-02-20 22:39:24 C 10 26 34.55 -16 06 16.6 V B72
2021-02-20 22:39:55 C 10 26 33.65 -16 06 13.5 V L54
2021-02-20 22:40:26 C 10 26 34.36 -16 06 15.3 V B72
2021-02-20 22:41:27 C 10 26 34.16 -16 06 14.1 V B72
2021-02-20 22:42:29 C 10 26 33.98 -16 06 13.4 V B72
2021-02-20 22:43:00 C 10 26 33.85 -16 06 12.3 V B72
2021-02-20 22:43:31 C 10 26 33.81 -16 06 12.2 V B72
2021-02-20 22:44:33 C 10 26 33.58 -16 06 10.9 V B72
2021-02-20 22:45:34 C 10 26 33.40 -16 06 10.1 V B72
2021-02-20 22:46:37 C 10 26 33.16 -16 06 08.7 V B72
2021-02-20 22:55:22 C 10 26 30.61 -16 05 55.8 V L54
2021-02-20 23:03:02 C 10 26 29.80 -16 05 45.7 V G17
2021-02-20 23:04:05 S 10 26 14.378 -16 21 00.72 V C57
2021-02-20 23:04:05 s 1 -181308.38 6 +58405.650 5930.0 C57
2021-02-20 23:05:43 C 10 26 29.31 -16 05 43.9 V G17
2021-02-20 23:07:09 C 10 26 28.43 -16 05 44.6 q 056
2021-02-20 23:08:24 C 10 26 28.76 -16 05 40.2 V G17
2021-02-20 23:14:05 S 10 26 12.108 -16 20 46.18 V C57
2021-02-20 23:14:05 s 1 -180977.58 0 +57531.848 2870.0 C57
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)