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
2021-03-13 12:41:40 C 08 56 30.12 -01 35 38.4 t P66
2021-03-13 13:07:33 C 08 56 25.70 -01 34 45.4 t P66
2021-03-13 13:08:04 C 08 56 25.70 -01 34 45.4 t P66
2021-03-13 13:34:09 C 08 56 21.25 -01 33 52.1 t P66
2021-03-13 13:34:39 C 08 56 21.25 -01 33 52.1 t P66
2021-03-13 14:00:33 C 08 56 16.85 -01 32 59.1 t P66
2021-03-13 14:01:02 C 08 56 16.85 -01 32 59.1 t P66
2021-03-13 14:53:28 C 08 56 08.08 -01 31 13.0 t P66
2021-03-13 14:53:58 C 08 56 08.08 -01 31 13.0 t P66
2021-03-13 15:19:49 C 08 56 03.75 -01 30 20.1 t P66
2021-03-13 15:20:19 C 08 56 03.75 -01 30 20.1 t P66
2021-03-13 16:41:15 C 08 55 54.76 -01 27 58.5 q 168
2021-03-13 16:49:16 C 08 55 53.49 -01 27 42.5 q 168
2021-03-13 17:03:15 C 08 55 51.25 -01 27 14.4 q 168
2021-03-13 17:59:30 C 08 55 42.24 -01 25 21.8 q 168
2021-03-13 18:17:30 C 08 55 39.37 -01 24 45.7 q 168
2021-03-13 19:00:26 C 08 55 34.97 -01 23 06.3 q K73
2021-03-13 19:07:01 C 08 55 33.89 -01 22 52.9 q K73
2021-03-13 19:14:46 C 08 55 32.81 -01 22 39.9 q L47
2021-03-13 19:34:33 C 08 55 29.60 -01 22 00.9 q L47
2021-03-13 19:50:30 C 08 55 27.07 -01 21 29.7 q L47
2021-03-13 20:03:54 C 08 55 24.56 -01 20 59.0 q K73
2021-03-13 20:12:48 C 08 55 22.70 -01 20 46.2 V L54
2021-03-13 21:01:05 C 08 55 15.20 -01 19 04.8 q K73
2021-03-13 21:04:28 C 08 55 14.63 -01 18 57.9 q K73
2021-03-13 21:07:10 C 08 55 14.21 -01 18 52.6 q K73
2021-03-13 21:36:54 C 08 55 09.10 -01 17 57.9 V L54
2021-03-13 22:00:33 C 08 55 05.90 -01 17 15.7 V C43
2021-03-13 22:12:51 C 08 55 03.92 -01 16 51.0 V C43
2021-03-13 22:22:06 C 08 55 03.23 -01 16 33.0 V Z80
2021-03-13 22:32:19 C 08 55 01.56 -01 16 12.3 V Z80
2021-03-13 22:37:45 C 08 55 00.73 -01 16 01.6 V Z80
2021-03-13 23:01:02 C 08 54 55.70 -01 15 09.3 V L54
2021-03-14 10:56:53 C 08 53 16.32 -00 51 11.7 t P66
2021-03-14 10:57:24 C 08 53 16.32 -00 51 11.7 t P66
2021-03-14 11:22:12 C 08 53 12.26 -00 50 21.3 t P66
2021-03-14 11:22:43 C 08 53 12.26 -00 50 21.3 t P66
2021-03-14 11:48:42 C 08 53 08.00 -00 49 28.8 t P66
2021-03-14 11:49:12 C 08 53 08.00 -00 49 28.8 t P66
2021-03-14 12:15:04 C 08 53 03.75 -00 48 36.3 t P66
2021-03-14 12:15:34 C 08 53 03.75 -00 48 36.3 t P66
2021-03-14 12:44:41 C 08 52 58.97 -00 47 37.6 t P66
2021-03-14 12:45:12 C 08 52 58.97 -00 47 37.6 t P66
2021-03-14 13:11:13 C 08 52 54.69 -00 46 45.0 t P66
2021-03-14 13:11:42 C 08 52 54.69 -00 46 45.0 t P66
2021-03-14 14:03:54 C 08 52 46.21 -00 45 00.3 t P66
2021-03-14 14:04:24 C 08 52 46.21 -00 45 00.3 t P66
2021-03-14 14:10:45 C 08 52 45.19 -00 44 47.9 t P66
2021-03-14 14:30:19 C 08 52 41.98 -00 44 07.9 t P66
2021-03-14 14:30:48 C 08 52 41.98 -00 44 07.9 t P66
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)