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 23:21:23 C 10 26 25.62 -16 05 27.8 q 056
2021-02-20 23:24:05 S 10 26 09.737 -16 20 31.81 V C57
2021-02-20 23:24:05 s 1 -180643.16 1 +56656.897 2950.0 C57
2021-02-20 23:34:05 S 10 26 07.284 -16 20 17.88 V C57
2021-02-20 23:34:05 s 1 -180305.10 5 +55780.805 6120.0 C57
2021-02-20 23:35:38 C 10 26 22.83 -16 05 11.4 q 056
2021-02-20 23:44:05 S 10 26 04.882 -16 20 03.84 V C57
2021-02-20 23:44:05 s 1 -179963.38 3 +54903.578 2310.0 C57
2021-02-20 23:54:05 S 10 26 02.520 -16 19 50.05 V C57
2021-02-20 23:54:05 s 1 -179617.97 1 +54025.224 1490.0 C57
2021-02-20 23:54:36 C 10 26 19.07 -16 04 49.6 q 056
2021-02-21 00:04:05 S 10 26 00.156 -16 19 35.18 V C57
2021-02-21 00:04:05 s 1 -179268.84 0 +53145.752 3590.0 C57
2021-02-21 00:14:05 S 10 25 57.758 -16 19 20.42 V C57
2021-02-21 00:14:05 s 1 -178915.96 3 +52265.168 8570.0 C57
2021-02-21 00:24:05 S 10 25 55.402 -16 19 06.28 V C57
2021-02-21 00:24:05 s 1 -178559.31 2 +51383.481 6370.0 C57
2021-02-21 00:34:05 S 10 25 53.047 -16 18 51.80 V C57
2021-02-21 00:34:05 s 1 -178198.86 1 +50500.700 6940.0 C57
2021-02-21 00:44:05 S 10 25 50.710 -16 18 35.93 V C57
2021-02-21 00:44:05 s 1 -177834.58 0 +49616.833 210.0 C57
2021-02-21 00:45:27 C 10 26 09.52 -16 03 48.0 V 104
2021-02-21 00:49:46 C 10 26 08.67 -16 03 43.1 V 104
2021-02-21 00:54:05 C 10 26 07.81 -16 03 38.0 V 104
2021-02-21 00:54:05 S 10 25 48.300 -16 18 23.15 V C57
2021-02-21 00:54:05 s 1 -177466.44 1 +48731.890 6150.0 C57
2021-02-21 01:04:05 S 10 25 45.842 -16 18 07.70 V C57
2021-02-21 01:04:05 s 1 -177094.41 5 +47845.878 4680.0 C57
2021-02-21 01:14:05 S 10 25 43.531 -16 17 54.02 V C57
2021-02-21 01:14:05 s 1 -176718.47 4 +46958.809 5750.0 C57
2021-02-21 01:24:05 S 10 25 41.105 -16 17 39.34 V C57
2021-02-21 01:24:05 s 1 -176338.58 8 +46070.690 9320.0 C57
2021-02-21 01:34:05 S 10 25 38.770 -16 17 24.14 V C57
2021-02-21 01:34:05 s 1 -175954.72 7 +45181.533 5310.0 C57
2021-02-21 01:44:05 S 10 25 36.379 -16 17 09.78 V C57
2021-02-21 01:44:05 s 1 -175566.86 2 +44291.347 3670.0 C57
2021-02-21 01:54:05 S 10 25 34.022 -16 16 54.84 V C57
2021-02-21 01:54:05 s 1 -175174.96 2 +43400.142 4350.0 C57
2021-02-21 02:04:05 S 10 25 31.601 -16 16 40.12 V C57
2021-02-21 02:04:05 s 1 -174778.99 7 +42507.930 7270.0 C57
2021-02-21 02:14:05 S 10 25 29.280 -16 16 25.18 V C57
2021-02-21 02:14:05 s 1 -174378.93 5 +41614.722 2390.0 C57
2021-02-21 02:24:05 S 10 25 26.882 -16 16 10.63 V C57
2021-02-21 02:24:05 s 1 -173974.74 6 +40720.528 9640.0 C57
2021-02-21 02:34:05 S 10 25 24.526 -16 15 55.91 V C57
2021-02-21 02:34:05 s 1 -173566.39 8 +39825.360 8960.0 C57
2021-02-21 02:44:05 S 10 25 22.114 -16 15 40.93 V C57
2021-02-21 02:44:05 s 1 -173153.85 9 +38929.231 290.0 C57
2021-02-21 02:54:05 S 10 25 19.798 -16 15 26.39 V C57
2021-02-21 02:54:05 s 1 -172737.09 7 +38032.151 3560.0 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)