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
2021-03-14 20:44:08 C 08 51 48.64 -00 31 57.2 V B18
2021-03-14 20:52:21 C 08 51 48.39 -00 31 41.1 V 073
2021-03-14 20:53:24 C 08 51 48.23 -00 31 39.0 V 073
2021-03-14 20:55:26 C 08 51 46.91 -00 31 35.0 V B18
2021-03-14 21:01:01 C 08 51 46.05 -00 31 24.0 V B18
2021-03-14 21:03:53 C 08 51 46.54 -00 31 18.4 V 073
2021-03-14 21:06:45 C 08 51 45.15 -00 31 12.5 V B18
2021-03-14 21:08:04 C 08 51 45.90 -00 31 10.2 V 073
2021-03-14 21:12:19 C 08 51 44.31 -00 31 01.6 V B18
2021-03-14 21:55:31 C 08 51 39.38 -00 29 36.5 V 160
2021-03-14 22:00:37 C 08 51 38.57 -00 29 26.4 V 160
2021-03-14 22:05:44 C 08 51 37.77 -00 29 16.2 V 160
2021-03-14 22:09:33 C 08 51 37.19 -00 29 15.5 V C43
2021-03-14 22:28:36 C 08 51 34.28 -00 28 37.8 V C43
2021-03-15 08:05:01 C 08 50 14.85 -00 09 07.8 V T08
2021-03-15 08:09:39 C 08 50 14.11 -00 08 58.7 V T08
2021-03-15 08:17:37 C 08 50 12.85 -00 08 43.1 V T08
2021-03-15 09:08:41 C 08 50 04.76 -00 07 02.7 V T08
2021-03-15 18:02:15 C 08 48 55.30 +00 10 00.2 q K73
2021-03-15 18:07:42 C 08 48 54.48 +00 10 10.8 q K73
2021-03-15 18:13:08 C 08 48 53.65 +00 10 21.4 q K73
2021-03-15 18:18:36 C 08 48 52.84 +00 10 32.0 q K73
2021-03-15 18:45:42 C 08 48 49.00 +00 11 22.3 t L89
2021-03-15 18:49:45 C 08 48 45.46 +00 11 51.0 q M44
2021-03-15 18:56:22 C 08 48 47.40 +00 11 43.1 t L89
2021-03-15 19:02:24 C 08 48 43.44 +00 12 15.5 q M44
2021-03-15 19:07:05 C 08 48 45.78 +00 12 04.1 t L89
2021-03-15 19:17:49 C 08 48 44.17 +00 12 25.0 t L89
2021-03-15 19:20:16 C 08 48 40.61 +00 12 49.6 q M44
2021-03-15 19:28:31 C 08 48 42.55 +00 12 45.8 t L89
2021-03-15 19:38:43 C 08 48 40.85 +00 13 06.3 q L47
2021-03-15 19:55:37 C 08 48 37.05 +00 13 38.3 c 095
2021-03-15 19:56:02 C 08 48 36.98 +00 13 38.9 c 095
2021-03-15 19:56:54 C 08 48 36.86 +00 13 40.7 c 095
2021-03-15 19:57:20 C 08 48 36.78 +00 13 41.5 c 095
2021-03-15 19:57:46 C 08 48 36.73 +00 13 42.4 c 095
2021-03-15 19:58:11 C 08 48 36.66 +00 13 43.3 c 095
2021-03-15 19:58:37 C 08 48 36.60 +00 13 44.0 c 095
2021-03-15 19:59:03 C 08 48 36.54 +00 13 44.8 c 095
2021-03-15 19:59:29 C 08 48 36.48 +00 13 45.8 c 095
2021-03-15 19:59:55 C 08 48 36.41 +00 13 46.6 c 095
2021-03-15 20:00:21 C 08 48 36.34 +00 13 47.4 c 095
2021-03-15 20:00:47 C 08 48 36.28 +00 13 48.2 c 095
2021-03-15 20:01:13 C 08 48 36.20 +00 13 49.0 c 095
2021-03-15 20:01:39 C 08 48 36.14 +00 13 49.9 c 095
2021-03-15 20:02:05 C 08 48 36.07 +00 13 50.8 c 095
2021-03-15 20:02:31 C 08 48 36.01 +00 13 51.6 c 095
2021-03-15 20:03:22 C 08 48 35.88 +00 13 53.1 c 095
2021-03-15 20:03:48 C 08 48 35.82 +00 13 54.2 c 095
2021-03-15 20:04:14 C 08 48 35.75 +00 13 54.9 c 095
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)