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
2021-03-06 02:44:05 S 09 25 15.763 -07 43 58.66 V C57
2021-03-06 02:44:05 s 1 -164981.31 6 +31097.350 5680.0 C57
2021-03-06 02:45:28 C 09 26 22.10 -07 34 27.0 q 726
2021-03-06 02:52:09 C 09 26 20.77 -07 34 13.2 q 726
2021-03-06 02:54:05 S 09 25 13.579 -07 43 37.45 V C57
2021-03-06 02:54:05 s 1 -164525.57 0 +30174.938 3510.0 C57
2021-03-06 02:56:12 C 09 26 19.97 -07 34 05.8 q 726
2021-03-06 03:04:05 S 09 25 11.354 -07 43 14.12 V C57
2021-03-06 03:04:05 s 1 -164065.04 0 +29251.653 2130.0 C57
2021-03-06 03:14:05 S 09 25 09.173 -07 42 52.63 V C57
2021-03-06 03:14:05 s 1 -163599.68 6 +28327.511 1450.0 C57
2021-03-06 03:24:05 S 09 25 06.948 -07 42 29.12 V C57
2021-03-06 03:24:05 s 1 -163129.46 8 +27402.530 1410.0 C57
2021-03-06 03:26:15 C 09 26 15.63 -07 32 53.8 o 691
2021-03-06 03:27:33 C 09 26 13.78 -07 33 04.1 q 726
2021-03-06 03:32:56 C 09 26 12.70 -07 32 53.5 q 726
2021-03-06 03:34:05 S 09 25 04.730 -07 42 07.09 V C57
2021-03-06 03:34:05 s 1 -162654.34 7 +26476.728 1910.0 C57
2021-03-06 03:37:59 C 09 26 11.71 -07 32 43.8 q 726
2021-03-06 03:44:05 S 09 25 02.542 -07 41 44.70 V C57
2021-03-06 03:44:05 s 1 -162174.28 1 +25550.126 2890.0 C57
2021-03-06 03:54:05 S 09 25 00.425 -07 41 21.08 V C57
2021-03-06 03:54:05 s 1 -161689.23 0 +24622.741 4250.0 C57
2021-03-06 04:04:05 S 09 24 58.147 -07 40 59.88 V C57
2021-03-06 04:04:05 s 1 -161199.15 3 +23694.594 5910.0 C57
2021-03-06 04:09:15 C 09 26 07.03 -07 31 29.9 o 691
2021-03-06 04:14:05 S 09 24 55.975 -07 40 35.94 V C57
2021-03-06 04:14:05 s 1 -160704.00 7 +22765.705 7790.0 C57
2021-03-06 04:14:33 C 09 26 05.91 -07 31 20.2 V I52
2021-03-06 04:18:03 C 09 26 05.20 -07 31 13.4 V I52
2021-03-06 04:21:33 C 09 26 04.51 -07 31 06.8 V I52
2021-03-06 04:24:05 S 09 24 53.822 -07 40 14.41 V C57
2021-03-06 04:24:05 s 1 -160203.75 1 +21836.095 9820.0 C57
2021-03-06 04:25:02 C 09 26 03.79 -07 30 59.6 V I52
2021-03-06 04:34:05 S 09 24 51.638 -07 39 52.02 V C57
2021-03-06 04:34:05 s 1 -159698.34 1 +20905.787 1890.0 C57
2021-03-06 04:44:05 S 09 24 49.421 -07 39 28.73 V C57
2021-03-06 04:44:05 s 1 -159187.73 4 +19974.801 3930.0 C57
2021-03-06 04:50:10 C 09 25 58.79 -07 30 09.8 o 691
2021-03-06 04:52:19 C 09 25 58.36 -07 30 05.7 o 691
2021-03-06 04:54:05 S 09 24 47.162 -07 39 07.16 V C57
2021-03-06 04:54:05 s 1 -158671.88 7 +19043.161 5840.0 C57
2021-03-06 05:04:05 S 09 24 45.079 -07 38 43.62 V C57
2021-03-06 05:04:05 s 1 -158150.75 6 +18110.890 7550.0 C57
2021-03-06 05:14:05 S 09 24 42.917 -07 38 21.73 V C57
2021-03-06 05:14:05 s 1 -157624.29 6 +17178.011 8950.0 C57
2021-03-06 05:22:24 C 09 25 52.28 -07 29 06.6 o 691
2021-03-06 05:24:05 S 09 24 40.714 -07 37 58.19 V C57
2021-03-06 05:24:05 s 1 -157092.46 1 +16244.551 9970.0 C57
2021-03-06 05:34:05 S 09 24 38.587 -07 37 35.15 V C57
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)