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
2021-02-24 22:24:05 S 10 12 13.877 -13 53 35.92 V C57
2021-02-24 22:24:05 s 1 +140482.92 3 +234366.53 4150.0 C57
2021-02-24 22:24:12 C 10 08 33.15 -14 00 56.5 V L54
2021-02-24 22:34:05 S 10 12 12.245 -13 53 22.13 V C57
2021-02-24 22:34:05 s 1 +140260.33 4 +234983.39 1190.0 C57
2021-02-24 22:54:05 S 10 12 09.173 -13 52 57.18 V C57
2021-02-24 22:54:05 s 1 +139812.25 7 +236212.21 9350.0 C57
2021-02-24 23:04:05 S 10 12 07.615 -13 52 44.08 V C57
2021-02-24 23:04:05 s 1 +139586.77 8 +236824.19 490.0 C57
2021-02-24 23:11:44 C 10 08 23.27 -13 59 46.6 V L54
2021-02-24 23:20:30 C 10 08 22.30 -13 59 34.3 V 204
2021-02-24 23:24:31 C 10 08 21.47 -13 59 28.3 V 204
2021-02-24 23:28:31 C 10 08 20.65 -13 59 22.5 V 204
2021-02-24 23:32:33 C 10 08 19.81 -13 59 16.5 V 204
2021-02-24 23:36:53 C 10 08 18.89 -13 59 10.0 V 204
2021-02-24 23:50:34 C 10 08 16.04 -13 58 49.5 V 203
2021-02-24 23:59:07 C 10 08 14.42 -13 58 40.4 V G33
2021-02-24 23:59:49 C 10 08 13.31 -13 58 34.9 V L54
2021-02-25 00:00:41 C 10 08 14.13 -13 58 37.5 V G33
2021-02-25 00:02:22 C 10 08 13.59 -13 58 32.1 V 203
2021-02-25 00:02:22 C 10 08 13.74 -13 58 35.1 V G33
2021-02-25 00:04:03 C 10 08 13.45 -13 58 32.7 V G33
2021-02-25 00:05:44 C 10 08 13.09 -13 58 30.4 V G33
2021-02-25 00:07:25 C 10 08 12.76 -13 58 27.6 V G33
2021-02-25 00:15:29 C 10 08 10.86 -13 58 12.6 V 203
2021-02-25 01:07:32 C 10 08 00.610 -13 56 49.65 V Z84
2021-02-25 01:59:51 C 10 07 49.680 -13 55 31.01 V Z84
2021-02-25 06:34:05 S 10 10 55.997 -13 43 05.52 V C57
2021-02-25 06:34:05 s 1 +128535.48 8 +262727.03 9670.0 C57
2021-02-25 07:44:05 S 10 10 44.556 -13 41 35.52 V C57
2021-02-25 07:44:05 s 1 +126672.89 8 +266477.27 4480.0 C57
2021-02-25 07:54:05 S 10 10 42.946 -13 41 22.92 V C57
2021-02-25 07:54:05 s 1 +126403.97 3 +267007.06 6440.0 C57
2021-02-25 08:04:05 S 10 10 41.299 -13 41 08.66 V C57
2021-02-25 08:04:05 s 1 +126134.35 0 +267535.37 6960.0 C57
2021-02-25 08:14:05 S 10 10 39.787 -13 40 57.18 V C57
2021-02-25 08:14:05 s 1 +125864.03 3 +268062.20 6040.0 C57
2021-02-25 08:24:05 S 10 10 37.990 -13 40 44.04 V C57
2021-02-25 08:24:05 s 1 +125593.02 6 +268587.56 3690.0 C57
2021-02-25 08:34:05 S 10 10 36.425 -13 40 29.96 V C57
2021-02-25 08:34:05 s 1 +125321.33 3 +269111.44 9930.0 C57
2021-02-25 08:44:05 S 10 10 34.738 -13 40 17.62 V C57
2021-02-25 08:44:05 s 1 +125048.95 8 +269633.85 4750.0 C57
2021-02-25 08:54:05 S 10 10 33.062 -13 40 04.04 V C57
2021-02-25 08:54:05 s 1 +124775.90 4 +270154.79 8170.0 C57
2021-02-25 09:04:05 S 10 10 31.452 -13 39 50.65 V C57
2021-02-25 09:04:05 s 1 +124502.17 6 +270674.26 190.0 C57
2021-02-25 09:14:05 S 10 10 29.784 -13 39 38.48 V C57
2021-02-25 09:14:05 s 1 +124227.77 7 +271192.26 820.0 C57
2021-02-25 09:24:05 S 10 10 28.106 -13 39 25.38 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)