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
2005-01-24 01:38:41 C 03 46 37.89 -01 08 25.8 c 844
2005-01-24 01:44:55 C 03 46 38.74 -01 08 16.8 c 844
2005-01-28 01:34:41 C 03 59 58.99 +01 12 01.6 o H06
2005-01-28 03:01:03 C 04 00 09.48 +01 14 00.2 o H06
2005-01-28 03:13:18 C 04 00 10.94 +01 14 16.9 o H06
2005-01-29 00:04:00 C 04 02 57.00 +01 42 42.7 r 932
2005-01-29 02:05:59 C 04 03 11.81 +01 45 27.1 r 932
2005-01-29 02:15:59 C 04 03 13.03 +01 45 40.2 r 932
2005-01-29 03:00:30 C 04 03 19.81 +01 46 47.3 r 701
2005-01-29 03:51:46 C 04 03 25.93 +01 47 56.0 r 701
2005-01-29 04:35:57 C 04 03 31.31 +01 48 55.3 r 701
2005-01-29 05:05:53 C 04 03 34.70 +01 49 34.3 o H06
2005-01-29 05:20:21 C 04 03 36.48 +01 49 53.8 o H06
2005-01-29 05:32:49 C 04 03 37.98 +01 50 10.5 o H06
2005-01-29 19:18:48 C 04 05 26.96 +02 08 20.3 r 185
2005-01-29 19:19:50 C 04 05 27.37 +02 08 25.9 r 941
2005-01-29 19:20:11 C 04 05 27.06 +02 08 22.4 r 143
2005-01-29 19:20:30 C 04 05 27.46 +02 08 26.8 r 941
2005-01-29 19:22:30 C 04 05 27.69 +02 08 29.5 r 941
2005-01-29 19:23:51 C 04 05 27.85 +02 08 31.3 r 941
2005-01-29 19:24:31 C 04 05 27.93 +02 08 32.3 r 941
2005-01-29 19:25:11 C 04 05 27.72 +02 08 28.4 r 185
2005-01-29 19:30:55 C 04 05 28.34 +02 08 36.6 r 143
2005-01-29 19:34:37 C 04 05 28.86 +02 08 41.0 r 185
2005-01-29 19:41:36 C 04 05 29.62 +02 08 50.7 r 143
2005-01-29 19:42:20 C 04 05 29.80 +02 08 51.2 r 185
2005-01-31 02:35:58 C 04 09 26.07 +02 48 52.6 r 932
2005-01-31 02:45:59 C 04 09 27.24 +02 49 05.3 r 932
2005-01-31 02:49:58 C 04 09 27.70 +02 49 10.2 r 932
2005-02-01 17:37:53 C 04 14 20.79 +03 37 16.6 o 198
2005-02-01 17:43:52 C 04 14 21.49 +03 37 24.0 o 198
2005-02-01 17:46:47 C 04 14 21.82 +03 37 27.5 o 198
2005-02-01 17:52:12 C 04 14 22.45 +03 37 34.1 o 198
2005-02-01 17:56:45 C 04 14 22.98 +03 37 39.7 o 198
2005-02-01 18:06:52 C 04 14 24.14 +03 37 52.0 o 198
2005-02-01 20:36:23 C 04 14 41.52 +03 40 57.9 r 176
2005-02-01 20:38:40 C 04 14 41.76 +03 41 00.5 r 176
2005-02-01 20:40:56 C 04 14 42.01 +03 41 03.0 r 176
2005-02-01 20:43:11 C 04 14 42.27 +03 41 05.6 r 176
2005-02-01 20:45:28 C 04 14 42.57 +03 41 09.0 r 176
2005-02-01 20:47:44 C 04 14 42.83 +03 41 11.3 r 176
2005-02-02 20:02:10 C 04 17 34.01 +04 08 53.2 c A53
2005-02-02 20:18:56 C 04 17 35.88 +04 09 12.1 c A53
2005-02-02 20:29:28 C 04 17 36.99 +04 09 24.7 c A53
2005-02-03 17:44:49 C 04 20 12.45 +04 34 00.3 o 084
2005-02-03 17:56:29 C 04 20 14.35 +04 34 21.3 c 104
2005-02-03 18:00:29 C 04 20 14.80 +04 34 26.0 c 104
2005-02-03 18:27:46 C 04 20 17.85 +04 34 57.3 c 104
2005-02-03 18:58:33 C 04 20 20.88 +04 35 24.7 o 084
2005-02-04 02:28:29 C 04 21 15.55 +04 44 13.0 r 448
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)