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
2021-03-30 21:01:07 C 08 14 38.89 +10 21 37.6 V Z43
2021-03-30 21:09:52 C 08 14 38.26 +10 21 49.4 V Z43
2021-03-30 22:05:57 C 08 14 34.41 +10 23 04.2 V Z80
2021-03-30 22:09:56 C 08 14 34.15 +10 23 09.6 V Z80
2021-03-30 22:13:56 C 08 14 33.86 +10 23 14.9 V Z80
2021-03-31 00:32:57 C 08 14 26.67 +10 27 57.9 q 834
2021-03-31 01:04:56 C 08 14 24.24 +10 28 41.8 q 834
2021-03-31 07:36:57 C 08 14 01.89 +10 36 49.2 V T08
2021-03-31 07:42:17 C 08 14 01.51 +10 36 56.3 V T08
2021-03-31 07:50:54 C 08 14 00.89 +10 37 08.0 V T08
2021-03-31 08:07:31 C 08 13 59.69 +10 37 30.6 V T08
2021-03-31 10:13:36 C 08 13 54.30 +10 41 18.8 V Q62
2021-03-31 10:18:33 C 08 13 53.95 +10 41 25.6 V Q62
2021-03-31 10:23:32 C 08 13 53.59 +10 41 32.4 V Q62
2021-03-31 10:28:29 C 08 13 53.23 +10 41 39.2 V Q62
2021-03-31 10:33:23 C 08 13 52.88 +10 41 45.9 V Q62
2021-03-31 13:02:01 C 08 13 43.33 +10 43 58.9 q 900
2021-03-31 13:12:07 C 08 13 42.65 +10 44 12.6 q 900
2021-03-31 13:23:00 C 08 13 41.91 +10 44 27.1 q 900
2021-03-31 13:33:11 C 08 13 41.24 +10 44 40.9 q 900
2021-03-31 18:49:01 C 08 13 26.49 +10 51 47.3 V L47
2021-03-31 18:57:55 C 08 13 24.51 +10 51 57.1 V C40
2021-03-31 19:00:59 C 08 13 24.30 +10 52 01.3 V C40
2021-03-31 19:19:15 C 08 13 24.36 +10 52 23.4 V 246
2021-03-31 19:19:51 C 08 13 24.32 +10 52 24.4 V 246
2021-03-31 19:20:14 C 08 13 24.30 +10 52 24.8 V 246
2021-03-31 19:20:32 C 08 13 24.28 +10 52 25.3 V 246
2021-03-31 19:21:17 C 08 13 24.24 +10 52 26.2 V 246
2021-03-31 19:21:57 C 08 13 24.18 +10 52 27.1 V 246
2021-03-31 19:31:10 C 08 13 23.58 +10 52 44.7 V L47
2021-03-31 20:32:58 C 08 13 18.41 +10 54 04.2 V C40
2021-03-31 20:45:12 C 08 13 17.66 +10 54 20.5 V C40
2021-03-31 21:49:27 S 08 13 16.42 +10 56 28.3 L C51
2021-04-01 03:12:13 C 08 12 59.29 +11 03 21.6 V 703
2021-04-01 03:19:58 C 08 12 58.76 +11 03 32.1 V 703
2021-04-01 03:27:44 C 08 12 58.24 +11 03 42.2 V 703
2021-04-01 03:35:30 C 08 12 57.69 +11 03 52.5 V 703
2021-04-01 04:05:54 S 08 12 56.33 +11 04 58.7 L C51
2021-04-01 05:40:09 S 08 12 51.36 +11 07 05.4 L C51
2021-04-01 07:14:13 S 08 12 46.42 +11 09 12.5 L C51
2021-04-01 07:49:35 C 08 12 42.99 +11 09 48.3 V T08
2021-04-01 08:04:13 C 08 12 41.99 +11 10 07.6 V T08
2021-04-01 08:11:38 C 08 12 41.50 +11 10 17.3 V T08
2021-04-01 08:16:16 C 08 12 41.19 +11 10 23.4 V T08
2021-04-01 09:33:08 C 08 12 38.06 +11 13 06.2 q E89
2021-04-01 09:39:25 C 08 12 37.61 +11 13 14.3 q E89
2021-04-01 09:45:42 C 08 12 37.18 +11 13 22.4 q E89
2021-04-01 11:56:36 S 08 12 31.72 +11 15 32.1 L C51
2021-04-01 15:04:55 S 08 12 22.05 +11 19 43.4 L C51
2021-04-01 18:57:31 C 08 12 09.07 +11 24 15.9 V C40
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)