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
2005-04-28 20:05:40 C 08 01 41.25 +18 48 51.3 r 941
2005-04-28 20:07:45 C 08 01 41.47 +18 48 51.1 r 941
2005-04-28 20:11:13 C 08 01 41.83 +18 48 50.9 r 941
2005-04-30 03:08:45 C 08 05 06.10 +18 47 34.6 r 734
2005-04-30 03:15:06 C 08 05 06.81 +18 47 34.2 r 734
2005-04-30 03:21:28 C 08 05 07.49 +18 47 34.0 r 734
2005-04-30 20:01:02 C 08 06 57.57 +18 46 43.1 r A13
2005-04-30 20:57:07 C 08 07 03.53 +18 46 41.0 r A13
2005-04-30 21:03:36 C 08 07 04.29 +18 46 38.7 r A13
2005-05-05 20:20:37 C 08 20 09.21 +18 38 40.5 r 941
2005-05-05 20:21:47 C 08 20 09.34 +18 38 40.3 r 941
2005-05-05 20:22:58 C 08 20 09.47 +18 38 40.1 r 941
2005-05-05 20:24:09 C 08 20 09.59 +18 38 39.9 r 941
2005-05-05 20:26:30 C 08 20 09.84 +18 38 39.7 r 941
2005-05-21 03:43:41 C 08 59 47.25 +17 52 33.9 r G96
2005-05-21 03:47:54 C 08 59 47.65 +17 52 33.5 r G96
2005-05-21 03:52:10 C 08 59 48.08 +17 52 32.4 r G96
2005-05-21 03:56:24 C 08 59 48.51 +17 52 31.6 r G96
2005-05-27 03:13:47 C 09 14 45.36 +17 28 32.7 r 734
2005-05-27 03:25:02 C 09 14 46.46 +17 28 30.1 r 734
2005-05-27 20:47:16 C 09 16 33.58 +17 25 27.9 r 941
2005-05-27 20:48:26 C 09 16 33.69 +17 25 27.7 r 941
2005-05-27 20:50:47 C 09 16 33.94 +17 25 27.1 r 941
2005-05-27 20:53:07 C 09 16 34.17 +17 25 26.6 r 941
2005-06-01 04:00:14 C 09 27 00.87 +17 07 15.1 d 291
2005-06-01 04:07:42 C 09 27 01.59 +17 07 13.5 d 291
2005-06-01 04:15:05 C 09 27 02.34 +17 07 12.1 d 291
2005-06-06 03:17:10 C 09 38 44.76 +16 46 02.1 r 734
2005-06-06 03:29:53 C 09 38 46.00 +16 46 00.3 r 734
2005-06-06 03:42:45 C 09 38 47.11 +16 45 57.8 r 734
2005-06-06 03:53:28 C 09 38 48.19 +16 45 55.5 r 734
2005-06-11 20:57:18 C 09 51 41.03 +16 22 52.6 r 941
2005-06-11 20:58:23 C 09 51 41.13 +16 22 52.6 r 941
2005-06-11 20:59:28 C 09 51 41.23 +16 22 52.5 r 941
2005-06-11 21:01:41 C 09 51 41.43 +16 22 52.3 r 941
2005-06-16 20:46:30 C 10 02 14.57 +16 05 30.0 r 941
2005-06-16 20:47:43 C 10 02 14.67 +16 05 29.7 r 941
2005-06-16 20:53:26 C 10 02 15.17 +16 05 28.7 r 941
2005-06-16 20:55:20 C 10 02 15.34 +16 05 28.2 r 941
2005-06-16 20:57:21 C 10 02 15.51 +16 05 27.9 r 941
2005-06-17 03:50:30 C 10 02 50.38 +16 04 38.2 r G96
2005-06-17 03:56:19 C 10 02 50.88 +16 04 37.2 r G96
2005-06-17 04:02:07 C 10 02 51.36 +16 04 36.3 r G96
2005-06-17 04:07:54 C 10 02 51.84 +16 04 35.2 r G96
2005-07-09 04:13:26 C 10 34 38.149 +16 12 41.50 L 695
2005-07-09 04:17:08 C 10 34 38.215 +16 12 42.47 o 695
2005-07-09 04:20:21 C 10 34 38.288 +16 12 42.68 L 695
2005-07-10 04:12:46 C 10 35 10.909 +16 18 25.82 L 695
2005-07-10 04:16:35 C 10 35 10.983 +16 18 26.48 L 695
2005-07-11 03:59:26 C 10 35 36.614 +16 24 45.48 o 695
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)