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
2004-12-27 18:11:27 C 01 06 13.15 -27 28 11.4 c 952
2004-12-27 18:15:49 C 01 06 14.90 -27 27 58.4 c 952
2004-12-27 18:17:52 C 01 06 15.72 -27 27 52.4 r 941
2004-12-27 18:20:10 C 01 06 16.66 -27 27 45.0 c 952
2004-12-27 18:20:24 C 01 06 16.74 -27 27 44.7 r 941
2004-12-27 18:24:32 C 01 06 18.42 -27 27 31.7 c 952
2004-12-27 18:25:29 C 01 06 18.79 -27 27 29.6 r 941
2004-12-27 18:27:11 C 01 06 19.48 -27 27 24.4 r 941
2004-12-27 18:32:50 C 01 06 21.75 -27 27 07.5 r 941
2004-12-27 18:49:00 C 01 06 28.14 -27 26 18.9 r 170
2004-12-27 18:51:32 C 01 06 29.15 -27 26 11.3 r 170
2004-12-27 18:52:35 C 01 06 29.58 -27 26 08.1 r 170
2004-12-27 19:00:09 C 01 06 32.62 -27 25 45.2 r 170
2004-12-27 19:01:50 C 01 06 33.30 -27 25 40.3 r 170
2004-12-27 19:03:42 C 01 06 34.21 -27 25 33.2 r 952
2004-12-27 19:04:34 C 01 06 34.39 -27 25 32.0 r 170
2004-12-27 19:12:09 C 01 06 37.62 -27 25 08.1 r 952
2004-12-27 19:20:52 C 01 06 41.11 -27 24 41.3 r 952
2004-12-27 19:29:35 C 01 06 44.66 -27 24 14.8 r 952
2004-12-27 19:38:18 C 01 06 48.11 -27 23 48.5 r 952
2004-12-27 19:46:59 C 01 06 51.67 -27 23 21.2 r 952
2004-12-28 02:01:46 C 01 09 29.63 -27 04 27.4 r 649
2004-12-28 02:05:53 C 01 09 31.37 -27 04 14.6 r 649
2004-12-28 02:10:00 C 01 09 32.89 -27 04 00.4 r 649
2004-12-28 02:14:06 C 01 09 34.57 -27 03 49.0 r 649
2004-12-28 02:18:12 C 01 09 36.22 -27 03 36.5 r 649
2004-12-28 10:07:22 C 01 12 50.81 -26 38 27.6 r 428
2004-12-28 10:08:56 C 01 12 51.43 -26 38 22.5 r 428
2004-12-28 10:10:31 C 01 12 52.08 -26 38 17.7 r 428
2004-12-28 10:12:05 C 01 12 52.68 -26 38 12.8 r 428
2004-12-28 10:13:39 C 01 12 53.24 -26 38 07.9 r 428
2004-12-29 00:35:48 C 01 18 47.23 -25 55 39.9 r 734
2004-12-29 00:37:24 C 01 18 47.80 -25 55 35.2 r 734
2004-12-29 00:39:00 C 01 18 48.46 -25 55 30.1 r 734
2004-12-29 00:40:37 C 01 18 49.04 -25 55 25.5 r 734
2004-12-29 10:17:54 C 01 22 37.04 -25 25 54.8 m 300
2004-12-29 10:20:21 C 01 22 37.96 -25 25 49.3 m 300
2004-12-29 10:22:49 C 01 22 38.99 -25 25 40.3 m 300
2004-12-29 10:33:34 C 01 22 41.04 -25 23 45.6 r 428
2004-12-29 10:35:07 C 01 22 41.55 -25 23 40.7 r 428
2004-12-29 10:36:42 C 01 22 42.13 -25 23 36.3 r 428
2004-12-29 10:38:17 C 01 22 42.80 -25 23 31.2 r 428
2004-12-29 10:39:50 C 01 22 43.33 -25 23 26.0 r 428
2004-12-30 11:34:51 C 01 32 15.533 -24 06 58.31 16.6 r 422
2004-12-30 11:36:07 C 01 32 15.979 -24 06 54.42 16.6 r 422
2004-12-30 11:37:35 C 01 32 16.499 -24 06 49.77 16.7 r 422
2004-12-30 11:52:41 C 01 32 22.01 -24 05 58.3 r 423
2004-12-30 12:01:15 C 01 32 25.09 -24 05 31.4 r 423
2004-12-30 17:04:47 C 01 34 22.88 -23 51 40.1 c 434
2004-12-30 17:07:17 C 01 34 23.61 -23 51 35.0 c 434
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)