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
2021-03-04 22:14:05 S 09 31 52.790 -08 44 24.58 V C57
2021-03-04 22:14:05 s 1 -194971.46 8 +170042.45 4080.0 C57
2021-03-04 22:24:05 S 09 31 50.434 -08 44 05.10 V C57
2021-03-04 22:24:05 s 1 -194987.27 4 +169347.83 4960.0 C57
2021-03-04 22:26:41 C 09 31 34.07 -08 29 43.1 V L54
2021-03-04 22:29:39 C 09 31 33.48 -08 29 37.3 V L54
2021-03-04 22:34:05 S 09 31 48.091 -08 43 43.86 V C57
2021-03-04 22:34:05 s 1 -195001.50 4 +168651.83 2930.0 C57
2021-03-04 22:39:32 C 09 31 30.55 -08 29 16.6 V C40
2021-03-04 22:43:19 C 09 31 30.71 -08 29 11.0 V L54
2021-03-04 22:44:05 S 09 31 45.691 -08 43 23.95 V C57
2021-03-04 22:44:05 s 1 -195014.14 9 +167954.47 7960.0 C57
2021-03-04 22:50:11 C 09 31 28.43 -08 28 55.9 V C40
2021-03-04 22:54:05 S 09 31 43.639 -08 43 07.82 V C57
2021-03-04 22:54:05 s 1 -195025.20 0 +167255.74 50.0 C57
2021-03-04 22:54:44 C 09 31 27.52 -08 28 46.7 V C40
2021-03-04 22:59:19 C 09 31 26.60 -08 28 37.8 V C40
2021-03-04 23:01:08 C 09 31 27.13 -08 28 36.3 V L54
2021-03-04 23:03:58 C 09 31 25.67 -08 28 28.8 V C40
2021-03-04 23:05:29 C 09 31 25.37 -08 28 25.7 V C40
2021-03-04 23:16:35 C 09 31 24.02 -08 28 05.8 V L54
2021-03-04 23:24:05 S 09 31 36.206 -08 42 02.70 V C57
2021-03-04 23:24:05 s 1 -195048.71 4 +165151.32 8430.0 C57
2021-03-04 23:24:18 C 09 31 22.47 -08 27 50.8 V L54
2021-03-04 23:27:04 C 09 31 21.07 -08 27 43.5 V C40
2021-03-04 23:31:56 C 09 31 20.09 -08 27 34.3 V C40
2021-03-04 23:34:05 S 09 31 33.842 -08 41 43.15 V C57
2021-03-04 23:34:05 s 1 -195053.31 0 +164447.10 8550.0 C57
2021-03-04 23:44:05 S 09 31 31.481 -08 41 22.27 V C57
2021-03-04 23:44:05 s 1 -195056.27 2 +163741.51 5640.0 C57
2021-03-04 23:54:05 S 09 31 29.095 -08 41 01.25 V C57
2021-03-04 23:54:05 s 1 -195057.59 0 +163034.54 9680.0 C57
2021-03-05 00:04:05 S 09 31 26.726 -08 40 41.59 V C57
2021-03-05 00:04:05 s 1 -195057.25 6 +162326.19 660.0 C57
2021-03-05 00:14:05 S 09 31 24.353 -08 40 21.83 V C57
2021-03-05 00:14:05 s 1 -195055.26 1 +161616.47 8560.0 C57
2021-03-05 00:24:05 S 09 31 21.986 -08 40 00.80 V C57
2021-03-05 00:24:05 s 1 -195051.59 7 +160905.36 3350.0 C57
2021-03-05 00:34:05 S 09 31 19.637 -08 39 39.74 V C57
2021-03-05 00:34:05 s 1 -195046.25 5 +160192.87 5030.0 C57
2021-03-05 00:44:05 S 09 31 17.201 -08 39 19.98 V C57
2021-03-05 00:44:05 s 1 -195039.22 6 +159479.00 3580.0 C57
2021-03-05 00:54:05 S 09 31 14.866 -08 38 59.53 V C57
2021-03-05 00:54:05 s 1 -195030.50 0 +158763.75 8980.0 C57
2021-03-05 01:04:05 S 09 31 12.439 -08 38 38.26 V C57
2021-03-05 01:04:05 s 1 -195020.06 9 +158047.11 1220.0 C57
2021-03-05 01:14:05 S 09 31 10.150 -08 38 18.78 V C57
2021-03-05 01:14:05 s 1 -195007.92 4 +157329.09 260.0 C57
2021-03-05 02:03:41 C 09 30 57.31 -08 22 37.6 V V93
2021-03-05 02:52:52 C 09 30 47.43 -08 21 03.2 V V93
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)