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
2021-03-16 16:36:06 C 08 45 51.75 +00 53 42.5 V N82
2021-03-16 16:59:39 C 08 45 48.36 +00 54 28.0 V N82
2021-03-16 17:23:20 C 08 45 44.98 +00 55 13.6 V N82
2021-03-16 17:47:01 C 08 45 41.60 +00 55 59.2 V N82
2021-03-16 18:10:41 C 08 45 38.26 +00 56 44.7 V N82
2021-03-16 18:34:21 C 08 45 34.93 +00 57 30.1 V N82
2021-03-16 18:50:57 C 08 45 33.32 +00 58 30.0 q C97
2021-03-16 18:52:22 C 08 45 33.07 +00 58 32.8 q C97
2021-03-16 18:53:03 C 08 45 32.98 +00 58 33.9 q C97
2021-03-16 18:53:46 C 08 45 32.88 +00 58 35.6 q C97
2021-03-16 18:54:29 C 08 45 32.79 +00 58 37.0 q C97
2021-03-16 19:02:04 C 08 45 31.08 +00 58 23.4 V N82
2021-03-16 21:14:10 C 08 45 15.77 +01 02 44.0 V 160
2021-03-16 21:17:00 C 08 45 15.35 +01 02 49.3 V 160
2021-03-16 21:19:51 C 08 45 14.93 +01 02 55.1 V 160
2021-03-16 21:57:16 C 08 45 10.32 +01 03 59.9 V Z80
2021-03-16 22:14:12 C 08 45 07.91 +01 04 32.3 V Z80
2021-03-16 22:25:24 C 08 45 06.34 +01 04 52.4 V Z99
2021-03-16 22:29:16 C 08 45 05.79 +01 04 59.9 V Z99
2021-03-16 22:31:06 C 08 45 05.49 +01 05 05.0 V Z80
2021-03-16 22:33:09 C 08 45 05.26 +01 05 07.3 V Z99
2021-03-16 22:37:04 C 08 45 04.69 +01 05 14.9 V Z99
2021-03-16 22:40:56 C 08 45 04.16 +01 05 22.5 V Z99
2021-03-16 22:45:02 C 08 45 02.72 +01 05 38.5 108
2021-03-16 22:48:01 C 08 45 03.11 +01 05 37.5 V Z80
2021-03-16 22:48:14 C 08 45 02.23 +01 05 45.0 108
2021-03-16 22:52:33 C 08 45 01.67 +01 05 53.4 108
2021-03-16 22:56:51 C 08 45 01.06 +01 06 01.2 108
2021-03-16 23:05:42 C 08 45 00.63 +01 06 11.6 V Z80
2021-03-17 11:24:06 C 08 43 28.32 +01 29 59.0 q Q21
2021-03-17 11:31:39 C 08 43 27.27 +01 30 13.8 q Q21
2021-03-17 11:39:13 C 08 43 26.15 +01 30 28.7 q Q21
2021-03-17 11:48:16 C 08 43 24.85 +01 30 45.2 q Q21
2021-03-17 12:32:45 C 08 43 19.32 +01 32 12.3 t P66
2021-03-17 12:42:14 C 08 43 17.97 +01 32 30.3 t P66
2021-03-17 12:52:48 C 08 43 16.45 +01 32 50.4 t P66
2021-03-17 13:03:19 C 08 43 14.94 +01 33 10.3 t P66
2021-03-17 13:13:52 C 08 43 13.43 +01 33 30.4 t P66
2021-03-17 13:24:29 C 08 43 11.91 +01 33 50.6 t P66
2021-03-17 13:35:02 C 08 43 10.40 +01 34 10.8 t P66
2021-03-17 13:45:33 C 08 43 08.91 +01 34 30.7 t P66
2021-03-17 13:56:19 C 08 43 07.38 +01 34 51.2 t P66
2021-03-17 14:06:50 C 08 43 05.88 +01 35 11.2 t P66
2021-03-17 14:17:38 C 08 43 04.36 +01 35 31.6 t P66
2021-03-17 14:31:16 C 08 43 02.44 +01 35 57.5 t P66
2021-03-17 14:42:04 C 08 43 00.91 +01 36 18.0 t P66
2021-03-17 14:52:35 C 08 42 59.44 +01 36 38.0 t P66
2021-03-17 15:03:18 C 08 42 57.95 +01 36 58.3 t P66
2021-03-17 15:13:58 C 08 42 56.46 +01 37 18.5 t P66
2021-03-17 19:04:54 C 08 42 31.21 +01 44 28.6 V L47
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)