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
2004-12-23 10:37:28 C 00 17 41.60 -32 22 03.6 r E12
2004-12-23 10:37:58 C 00 17 41.76 -32 22 01.9 r E12
2004-12-23 10:38:28 C 00 17 42.05 -32 22 00.5 r E12
2004-12-23 10:38:58 C 00 17 42.30 -32 21 59.6 r E12
2004-12-23 10:39:56 C 00 17 42.75 -32 21 56.8 r E12
2004-12-23 10:40:25 C 00 17 43.01 -32 21 55.3 r E12
2004-12-23 10:40:55 C 00 17 43.27 -32 21 54.2 r E12
2004-12-23 10:41:26 C 00 17 43.50 -32 21 52.6 r E12
2004-12-23 11:36:56 C 00 18 10.63 -32 19 20.8 r E12
2004-12-23 11:37:26 C 00 18 10.94 -32 19 20.2 r E12
2004-12-23 11:37:58 C 00 18 11.15 -32 19 17.9 r E12
2004-12-23 11:38:28 C 00 18 11.37 -32 19 16.8 r E12
2004-12-23 11:44:38 C 00 18 14.43 -32 18 59.6 r E12
2004-12-23 11:45:09 C 00 18 14.66 -32 18 58.0 r E12
2004-12-23 11:45:38 C 00 18 14.95 -32 18 57.6 r E12
2004-12-23 11:46:08 C 00 18 15.16 -32 18 56.1 r E12
2004-12-23 12:46:10 C 00 18 44.87 -32 16 09.7 r E12
2004-12-23 12:46:41 C 00 18 45.08 -32 16 07.8 r E12
2004-12-23 12:47:11 C 00 18 45.34 -32 16 07.1 r E12
2004-12-23 12:47:43 C 00 18 45.67 -32 16 05.6 r E12
2004-12-24 01:50:17 C 00 25 23.84 -31 43 12.7 m 683
2004-12-24 01:54:52 C 00 25 26.08 -31 43 00.1 m 683
2004-12-24 02:38:38 C 00 25 46.71 -31 41 02.6 o 699
2004-12-24 02:49:12 C 00 25 51.71 -31 40 33.3 o 699
2004-12-24 02:59:47 C 00 25 56.71 -31 40 04.2 o 699
2004-12-24 03:10:22 C 00 26 01.70 -31 39 35.4 o 699
2004-12-24 03:35:43 C 00 26 13.82 -31 38 26.2 o 699
2004-12-24 03:39:44 C 00 26 15.53 -31 38 12.6 o 699
2004-12-24 03:43:45 C 00 26 17.51 -31 38 02.8 o 699
2004-12-24 03:47:47 C 00 26 19.41 -31 37 50.6 o 699
2004-12-24 18:00:50 C 00 33 20.811 -30 58 58.19 o 620
2004-12-24 18:12:33 C 00 33 26.197 -30 58 25.32 o 620
2004-12-24 18:23:23 C 00 33 31.205 -30 57 55.28 o 620
2004-12-25 01:34:58 C 00 36 58.97 -30 37 42.5 o H06
2004-12-25 01:42:49 C 00 37 02.54 -30 37 20.2 o H06
2004-12-25 01:48:08 C 00 37 05.59 -30 37 05.1 m 683
2004-12-25 01:51:32 C 00 37 07.12 -30 36 55.6 m 683
2004-12-25 01:52:04 C 00 37 06.76 -30 36 54.3 o H06
2004-12-25 01:54:09 C 00 37 08.27 -30 36 49.2 m 683
2004-12-25 01:56:47 C 00 37 09.45 -30 36 40.6 m 683
2004-12-25 01:59:30 C 00 37 10.73 -30 36 33.3 m 683
2004-12-25 02:02:06 C 00 37 11.93 -30 36 26.4 m 683
2004-12-25 02:05:55 C 00 37 13.60 -30 36 15.0 m 683
2004-12-25 02:12:07 C 00 37 16.43 -30 35 57.5 m 683
2004-12-25 02:24:41 C 00 37 22.07 -30 35 22.0 m 683
2004-12-25 02:30:00 C 00 37 24.51 -30 35 07.0 m 683
2004-12-25 02:35:41 C 00 37 27.10 -30 34 50.3 m 683
2004-12-25 02:45:09 C 00 37 31.33 -30 34 22.7 m 683
2004-12-25 02:52:09 C 00 37 34.49 -30 34 03.3 m 683
2004-12-25 02:55:06 C 00 37 35.88 -30 33 55.1 m 683
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)