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
2021-02-16 20:34:01 C 10 43 43.34 -17 41 02.1 V 221
2021-02-16 20:35:45 C 10 43 43.01 -17 41 00.8 V 221
2021-02-16 20:57:38 C 10 43 39.12 -17 40 44.4 V 221
2021-02-16 20:59:22 C 10 43 38.81 -17 40 43.1 V 221
2021-02-16 21:01:28 C 10 43 38.41 -17 40 41.4 V 221
2021-02-16 21:18:05 C 10 43 35.44 -17 40 28.9 V 221
2021-02-16 21:19:48 C 10 43 35.12 -17 40 27.5 V 221
2021-02-16 21:21:44 C 10 43 34.77 -17 40 26.1 V 221
2021-02-16 21:35:44 C 10 43 31.35 -17 41 24.5 V L54
2021-02-16 21:44:22 C 10 43 29.79 -17 41 17.9 V L54
2021-02-16 21:44:53 C 10 43 30.57 -17 40 08.3 V 221
2021-02-16 21:46:53 C 10 43 30.22 -17 40 06.7 V 221
2021-02-16 21:48:36 C 10 43 29.89 -17 40 05.3 V 221
2021-02-16 21:55:04 C 10 43 27.89 -17 41 08.8 V L54
2021-02-16 22:10:28 C 10 43 25.90 -17 39 48.4 V 221
2021-02-16 22:12:21 C 10 43 25.56 -17 39 46.9 V 221
2021-02-16 22:14:07 C 10 43 25.23 -17 39 45.5 V 221
2021-02-16 23:00:17 C 10 43 17.782 -17 40 09.35 V Z84
2021-02-17 00:00:34 C 10 43 06.858 -17 39 21.53 V Z84
2021-02-17 00:08:16 C 10 43 05.12 -17 39 23.5 V Z80
2021-02-17 00:17:41 C 10 43 03.45 -17 39 15.8 V Z80
2021-02-17 01:00:52 C 10 42 55.841 -17 38 32.48 V Z84
2021-02-17 02:00:35 C 10 42 44.920 -17 37 42.51 V Z84
2021-02-17 03:00:52 C 10 42 33.941 -17 36 50.76 V Z84
2021-02-17 07:17:43 C 10 41 54.01 -17 33 12.3 o 691
2021-02-17 07:19:31 C 10 41 53.67 -17 33 10.8 o 691
2021-02-17 07:21:17 C 10 41 53.34 -17 33 09.3 o 691
2021-02-17 18:46:15 C 10 39 59.49 -17 23 03.7 V M44
2021-02-17 19:05:00 C 10 39 54.19 -17 23 06.1 N42
2021-02-17 19:06:18 C 10 39 53.96 -17 23 05.1 N42
2021-02-17 19:06:21 C 10 39 55.89 -17 22 49.3 V M44
2021-02-17 19:07:35 C 10 39 53.75 -17 23 03.9 N42
2021-02-17 19:08:53 C 10 39 53.48 -17 23 02.8 N42
2021-02-17 19:10:10 C 10 39 53.25 -17 23 01.6 N42
2021-02-17 19:11:27 C 10 39 53.01 -17 23 00.5 N42
2021-02-17 19:12:44 C 10 39 52.77 -17 22 59.4 N42
2021-02-17 19:14:01 C 10 39 52.53 -17 22 58.2 N42
2021-02-17 19:15:19 C 10 39 52.29 -17 22 57.2 N42
2021-02-17 19:16:36 C 10 39 52.07 -17 22 56.3 N42
2021-02-17 19:17:54 C 10 39 51.82 -17 22 54.8 N42
2021-02-17 19:19:11 C 10 39 51.57 -17 22 53.7 N42
2021-02-17 19:20:28 C 10 39 51.34 -17 22 52.5 N42
2021-02-17 19:21:45 C 10 39 51.10 -17 22 51.4 N42
2021-02-17 19:23:02 C 10 39 50.86 -17 22 50.3 N42
2021-02-17 19:24:20 C 10 39 50.62 -17 22 49.2 N42
2021-02-17 19:25:37 C 10 39 50.38 -17 22 47.9 N42
2021-02-17 19:26:25 C 10 39 52.04 -17 22 32.2 V M44
2021-02-17 19:26:55 C 10 39 50.14 -17 22 46.8 N42
2021-02-17 19:28:12 C 10 39 49.90 -17 22 45.7 N42
2021-02-17 19:29:29 C 10 39 49.67 -17 22 44.7 N42
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)