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
2004-03-15 02:35:21 C 04 06 08.08 +16 55 04.6 o 691
2004-03-15 02:38:57 C 04 06 08.58 +16 55 06.1 o 691
2004-03-15 02:58:03 C 04 06 11.75 +16 55 15.5 o 691
2004-03-15 03:01:50 C 04 06 12.40 +16 55 17.7 o 691
2004-03-15 03:17:36 C 04 06 14.90 +16 55 25.4 o 691
2004-03-15 03:21:34 C 04 06 15.58 +16 55 27.1 o 691
2004-06-19 04:05:00 C 09 44 29.677 +13 18 50.67 L 695
2004-06-19 04:05:00 X 09 44 29.658 +13 18 50.95 o 695
2004-06-19 04:11:47 C 09 44 30.604 +13 18 46.81 L 695
2004-06-19 04:18:44 C 09 44 31.507 +13 18 42.91 L 695
2004-06-20 03:49:42 C 09 47 41.116 +13 05 24.49 L 695
2004-06-20 03:56:36 C 09 47 42.006 +13 05 20.50 L 695
2004-06-20 04:03:27 C 09 47 42.926 +13 05 16.74 L 695
2004-12-18 10:09:22 C 23 12 07.07 -36 37 10.2 r E12
2004-12-18 10:20:23 C 23 12 13.22 -36 36 52.6 r E12
2004-12-18 10:31:22 C 23 12 19.16 -36 36 34.0 r E12
2004-12-18 10:42:23 C 23 12 25.19 -36 36 14.7 r E12
2004-12-18 10:55:55 C 23 12 32.70 -36 35 52.1 r E12
2004-12-18 10:57:05 C 23 12 33.34 -36 35 50.2 r E12
2004-12-18 10:58:16 C 23 12 33.99 -36 35 48.0 r E12
2004-12-18 10:59:25 C 23 12 34.64 -36 35 45.6 r E12
2004-12-18 11:46:20 C 23 13 00.72 -36 34 24.5 r E12
2004-12-18 11:47:30 C 23 13 01.34 -36 34 22.1 r E12
2004-12-18 11:48:40 C 23 13 02.02 -36 34 20.7 r E12
2004-12-18 11:49:50 C 23 13 02.61 -36 34 18.6 r E12
2004-12-19 01:53:47 C 23 21 05.63 -36 12 57.6 c 854
2004-12-19 02:00:43 C 23 21 09.30 -36 12 42.9 c 854
2004-12-19 02:07:41 C 23 21 13.23 -36 12 31.5 c 854
2004-12-19 02:14:41 C 23 21 16.88 -36 12 20.1 c 854
2004-12-19 02:21:50 C 23 21 20.79 -36 12 07.1 c 854
2004-12-19 11:01:34 C 23 26 11.18 -35 54 52.0 c 474
2004-12-19 11:03:14 C 23 26 12.10 -35 54 48.7 c 474
2004-12-19 11:04:24 C 23 26 12.73 -35 54 46.6 c 474
2004-12-19 11:09:04 C 23 26 15.34 -35 54 37.2 c 474
2004-12-20 01:39:39 C 23 34 27.46 -35 29 30.2 c 673
2004-12-20 01:50:45 C 23 34 33.36 -35 29 07.9 c 673
2004-12-20 01:59:19 C 23 34 37.90 -35 28 51.3 c 673
2004-12-20 02:09:35 C 23 34 43.37 -35 28 30.6 c 673
2004-12-22 11:20:39 C 00 05 38.68 -33 20 43.4 r E12
2004-12-22 11:21:11 C 00 05 38.95 -33 20 42.2 r E12
2004-12-22 11:21:42 C 00 05 39.14 -33 20 41.1 r E12
2004-12-22 11:22:12 C 00 05 39.50 -33 20 39.4 r E12
2004-12-23 01:32:15 C 00 13 05.41 -32 46 52.9 17.3 c 704
2004-12-23 01:32:19 C 00 13 05.63 -32 46 54.1 18.2 c 704
2004-12-23 02:11:35 C 00 13 24.67 -32 45 13.5 17.7 c 704
2004-12-23 02:13:34 C 00 13 25.79 -32 45 09.4 17.5 c 704
2004-12-23 02:31:28 C 00 13 34.51 -32 44 20.7 17.7 c 704
2004-12-23 02:34:58 C 00 13 36.28 -32 44 13.3 17.8 c 704
2004-12-23 02:51:06 C 00 13 44.09 -32 43 30.1 17.5 c 704
2004-12-23 02:55:14 C 00 13 46.17 -32 43 20.2 17.5 c 704
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)