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
2021-03-05 11:54:05 s 1 -190186.83 4 +108450.41 7210.0 C57
2021-03-05 12:04:05 S 09 28 37.015 -08 15 49.14 V C57
2021-03-05 12:04:05 s 1 -190039.71 6 +107640.57 3530.0 C57
2021-03-05 12:14:05 S 09 28 34.716 -08 15 29.12 V C57
2021-03-05 12:14:05 s 1 -189890.08 4 +106829.31 5120.0 C57
2021-03-05 12:24:05 S 09 28 32.330 -08 15 07.74 V C57
2021-03-05 12:24:05 s 1 -189737.92 1 +106016.63 1930.0 C57
2021-03-05 12:34:05 S 09 28 29.969 -08 14 46.25 V C57
2021-03-05 12:34:05 s 1 -189583.21 3 +105202.53 3930.0 C57
2021-03-05 12:44:05 S 09 28 27.670 -08 14 25.01 V C57
2021-03-05 12:44:05 s 1 -189425.94 2 +104387.01 1110.0 C57
2021-03-05 12:54:05 S 09 28 25.308 -08 14 04.45 V C57
2021-03-05 12:54:05 s 1 -189266.09 2 +103570.07 3420.0 C57
2021-03-05 13:54:05 S 09 28 11.374 -08 11 56.94 V C57
2021-03-05 13:54:05 s 1 -188251.89 1 +98638.739 3220.0 C57
2021-03-05 14:04:05 S 09 28 09.053 -08 11 36.17 V C57
2021-03-05 14:04:05 s 1 -188073.51 4 +97811.906 540.0 C57
2021-03-05 14:14:05 S 09 28 06.754 -08 11 13.81 V C57
2021-03-05 14:14:05 s 1 -187892.42 1 +96983.665 2720.0 C57
2021-03-05 14:24:05 S 09 28 04.397 -08 10 53.33 V C57
2021-03-05 14:24:05 s 1 -187708.59 4 +96154.015 9730.0 C57
2021-03-05 14:34:05 S 09 28 02.090 -08 10 32.48 V C57
2021-03-05 14:34:05 s 1 -187522.01 4 +95322.960 1540.0 C57
2021-03-05 14:44:05 S 09 27 59.724 -08 10 10.06 V C57
2021-03-05 14:44:05 s 1 -187332.66 4 +94490.500 8100.0 C57
2021-03-05 14:54:05 S 09 27 57.442 -08 09 49.64 V C57
2021-03-05 14:54:05 s 1 -187140.52 5 +93656.637 9390.0 C57
2021-03-05 15:04:05 S 09 27 55.092 -08 09 28.66 V C57
2021-03-05 15:04:05 s 1 -186945.57 9 +92821.372 5370.0 C57
2021-03-05 15:14:05 S 09 27 53.263 -08 09 02.95 V C57
2021-03-05 15:14:05 s 1 -186747.80 6 +91984.708 5990.0 C57
2021-03-05 15:24:05 S 09 27 50.429 -08 08 45.35 V C57
2021-03-05 15:24:05 s 1 -186547.18 8 +91146.646 1230.0 C57
2021-03-05 15:24:33 C 09 28 27.14 -07 56 48.2 V N82
2021-03-05 15:34:05 S 09 27 48.146 -08 08 24.43 V C57
2021-03-05 15:34:05 s 1 -186343.70 5 +90307.189 1040.0 C57
2021-03-05 15:44:05 S 09 27 45.782 -08 08 02.51 V C57
2021-03-05 15:44:05 s 1 -186137.33 9 +89466.337 5390.0 C57
2021-03-05 15:46:53 C 09 28 22.69 -07 56 04.6 V N82
2021-03-05 15:54:05 S 09 27 43.517 -08 07 41.34 V C57
2021-03-05 15:54:05 s 1 -185928.06 9 +88624.093 4240.0 C57
2021-03-05 16:09:13 C 09 28 18.23 -07 55 21.0 V N82
2021-03-05 16:14:05 S 09 27 38.858 -08 06 58.32 V C57
2021-03-05 16:14:05 s 1 -185500.74 1 +86935.440 5280.0 C57
2021-03-05 16:16:06 C 09 28 19.40 -07 55 00.4 V C40
2021-03-05 16:26:53 C 09 28 17.31 -07 54 39.6 V C40
2021-03-05 16:51:43 C 09 28 12.46 -07 53 51.7 V C40
2021-03-05 16:56:21 C 09 28 11.55 -07 53 42.7 V C40
2021-03-05 17:12:55 C 09 28 08.30 -07 53 10.6 V C40
2021-03-05 17:25:16 C 09 28 05.87 -07 52 46.8 V C40
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)