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
2021-03-06 09:14:05 S 09 23 51.638 -07 29 10.75 V C57
2021-03-06 09:14:05 s 1 -143266.40 9 - 5318.336 4220.0 C57
2021-03-06 09:24:05 S 09 23 49.584 -07 28 48.14 V C57
2021-03-06 09:24:05 s 1 -142590.84 9 - 6256.428 6300.0 C57
2021-03-06 09:34:05 S 09 23 47.515 -07 28 24.35 V C57
2021-03-06 09:34:05 s 1 -141908.63 2 - 7194.225 5410.0 C57
2021-03-06 09:44:05 S 09 23 45.413 -07 28 01.42 V C57
2021-03-06 09:44:05 s 1 -141219.70 0 - 8131.679 1440.0 C57
2021-03-06 09:54:05 S 09 23 43.354 -07 27 38.05 V C57
2021-03-06 09:54:05 s 1 -140523.99 7 - 9068.741 4270.0 C57
2021-03-06 10:04:05 S 09 23 41.244 -07 27 14.69 V C57
2021-03-06 10:04:05 s 1 -139821.46 2 -10005.359 3770.0 C57
2021-03-06 10:14:05 S 09 23 39.202 -07 26 51.25 V C57
2021-03-06 10:14:05 s 1 -139112.03 8 -10941.482 9830.0 C57
2021-03-06 10:24:05 S 09 23 37.114 -07 26 27.96 V C57
2021-03-06 10:24:05 s 1 -138395.66 3 -11877.056 2330.0 C57
2021-03-06 10:34:05 S 09 23 35.112 -07 26 04.96 V C57
2021-03-06 10:34:05 s 1 -137672.28 0 -12812.026 1150.0 C57
2021-03-06 10:44:05 S 09 23 33.046 -07 25 41.20 V C57
2021-03-06 10:44:05 s 1 -136941.82 6 -13746.336 6160.0 C57
2021-03-06 10:54:05 S 09 23 30.962 -07 25 18.08 V C57
2021-03-06 10:54:05 s 1 -136204.24 1 -14679.928 7230.0 C57
2021-03-06 11:04:05 S 09 23 28.949 -07 24 54.32 V C57
2021-03-06 11:04:05 s 1 -135459.46 4 -15612.743 4250.0 C57
2021-03-06 11:09:34 C 09 24 50.29 -07 17 44.2 q Q21
2021-03-06 11:14:05 S 09 23 26.887 -07 24 31.43 V C57
2021-03-06 11:14:05 s 1 -134707.43 2 -16544.719 7090.0 C57
2021-03-06 11:15:37 C 09 24 49.10 -07 17 32.2 q Q21
2021-03-06 11:21:40 C 09 24 47.90 -07 17 20.7 q Q21
2021-03-06 11:24:05 S 09 23 24.852 -07 24 07.06 V C57
2021-03-06 11:24:05 s 1 -133948.08 5 -17475.795 5620.0 C57
2021-03-06 11:29:13 C 09 24 46.35 -07 17 05.5 q Q21
2021-03-06 11:36:49 C 09 24 44.85 -07 16 50.8 q Q21
2021-03-06 12:36:29 C 09 24 28.20 -07 14 30.3 V T08
2021-03-06 12:44:40 C 09 24 26.61 -07 14 13.8 V T08
2021-03-06 13:10:03 C 09 24 21.72 -07 13 22.6 V T08
2021-03-06 13:13:14 C 09 24 21.12 -07 13 16.1 V T08
2021-03-06 18:04:43 C 09 23 35.07 -07 04 01.0 V A84
2021-03-06 18:06:33 C 09 23 34.71 -07 03 57.2 V A84
2021-03-06 18:08:22 C 09 23 34.36 -07 03 53.7 V A84
2021-03-06 18:10:12 C 09 23 33.98 -07 03 50.1 V A84
2021-03-06 18:12:02 C 09 23 33.64 -07 03 46.5 V A84
2021-03-06 18:12:29 C 09 23 31.43 -07 04 02.9 q 168
2021-03-06 18:13:52 C 09 23 33.28 -07 03 42.9 V A84
2021-03-06 18:15:41 C 09 23 32.92 -07 03 39.3 V A84
2021-03-06 18:17:31 C 09 23 32.55 -07 03 35.7 V A84
2021-03-06 18:19:21 C 09 23 32.20 -07 03 32.1 V A84
2021-03-06 18:24:44 C 09 23 31.93 -07 03 26.3 V K83
2021-03-06 18:24:50 C 09 23 31.11 -07 03 21.3 V A84
2021-03-06 18:26:30 C 09 23 28.73 -07 03 35.1 q 168
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)