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
2021-03-03 12:44:05 S 09 39 49.318 -09 49 20.35 V C57
2021-03-03 12:44:05 s 1 -167907.76 1 +283742.28 9810.0 C57
2021-03-03 12:54:05 S 09 39 46.980 -09 49 01.85 V C57
2021-03-03 12:54:05 s 1 -168130.80 5 +283296.01 6620.0 C57
2021-03-03 13:04:05 S 09 39 44.686 -09 48 42.77 V C57
2021-03-03 13:04:05 s 1 -168353.18 1 +282848.62 2250.0 C57
2021-03-03 13:14:05 S 09 39 42.358 -09 48 23.80 V C57
2021-03-03 13:14:05 s 1 -168574.88 7 +282400.10 6700.0 C57
2021-03-03 13:24:05 S 09 39 39.960 -09 48 05.62 V C57
2021-03-03 13:24:05 s 1 -168795.92 1 +281950.46 9970.0 C57
2021-03-03 13:34:05 S 09 39 37.579 -09 47 47.80 V C57
2021-03-03 13:34:05 s 1 -169016.28 0 +281499.69 2050.0 C57
2021-03-03 13:44:05 S 09 39 35.198 -09 47 28.75 V C57
2021-03-03 13:44:05 s 1 -169235.96 1 +281047.80 2930.0 C57
2021-03-03 13:54:05 S 09 39 32.858 -09 47 09.17 V C57
2021-03-03 13:54:05 s 1 -169454.96 2 +280594.78 2610.0 C57
2021-03-03 14:04:05 S 09 39 30.518 -09 46 50.77 V C57
2021-03-03 14:04:05 s 1 -169673.28 1 +280140.63 1090.0 C57
2021-03-03 14:14:05 S 09 39 28.190 -09 46 32.66 V C57
2021-03-03 14:14:05 s 1 -169890.91 4 +279685.35 8360.0 C57
2021-03-03 14:24:05 S 09 39 25.795 -09 46 14.70 V C57
2021-03-03 14:24:05 s 1 -170107.86 0 +279228.95 4410.0 C57
2021-03-03 14:34:05 S 09 39 23.465 -09 45 55.58 V C57
2021-03-03 14:34:05 s 1 -170324.11 6 +278771.41 9250.0 C57
2021-03-03 14:44:05 S 09 39 21.110 -09 45 35.53 V C57
2021-03-03 14:44:05 s 1 -170539.67 9 +278312.75 2860.0 C57
2021-03-03 14:54:05 S 09 39 18.734 -09 45 17.24 V C57
2021-03-03 14:54:05 s 1 -170754.54 6 +277852.95 5240.0 C57
2021-03-03 15:04:05 S 09 39 16.332 -09 44 59.46 V C57
2021-03-03 15:04:05 s 1 -170968.71 5 +277392.01 6390.0 C57
2021-03-03 15:14:05 S 09 39 13.975 -09 44 41.32 V C57
2021-03-03 15:14:05 s 1 -171182.18 4 +276929.94 6300.0 C57
2021-03-03 15:24:05 S 09 39 11.664 -09 44 21.44 V C57
2021-03-03 15:24:05 s 1 -171394.94 9 +276466.74 4960.0 C57
2021-03-03 15:33:09 C 09 37 25.078 -09 28 27.04 V O85
2021-03-03 15:34:05 S 09 39 09.317 -09 44 02.26 V C57
2021-03-03 15:34:05 s 1 -171607.00 9 +276002.40 2380.0 C57
2021-03-03 15:44:02 C 09 37 22.806 -09 28 06.46 V O85
2021-03-03 15:44:05 S 09 39 06.982 -09 43 44.08 V C57
2021-03-03 15:44:05 s 1 -171818.35 9 +275536.92 8540.0 C57
2021-03-03 15:45:36 C 09 37 22.462 -09 28 03.80 V O85
2021-03-03 15:46:56 C 09 37 22.201 -09 28 00.98 V O85
2021-03-03 15:48:30 C 09 37 21.871 -09 27 58.36 V O85
2021-03-03 15:49:50 C 09 37 21.602 -09 27 55.62 V O85
2021-03-03 15:51:24 C 09 37 21.270 -09 27 52.60 V O85
2021-03-03 15:52:44 C 09 37 20.986 -09 27 50.10 V O85
2021-03-03 15:54:05 S 09 39 04.627 -09 43 26.08 V C57
2021-03-03 15:54:05 s 1 -172028.99 9 +275070.31 3440.0 C57
2021-03-03 15:54:18 C 09 37 20.645 -09 27 47.48 V O85
2021-03-03 15:57:12 C 09 37 20.060 -09 27 41.78 V O85
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)