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
2021-03-05 23:58:24 C 09 26 49.51 -07 39 55.5 q G07
2021-03-06 00:04:05 S 09 25 51.473 -07 49 55.24 V C57
2021-03-06 00:04:05 s 1 -171653.04 4 +45724.464 7840.0 C57
2021-03-06 00:14:05 S 09 25 49.231 -07 49 33.38 V C57
2021-03-06 00:14:05 s 1 -171268.83 4 +44818.070 3140.0 C57
2021-03-06 00:16:39 C 09 26 50.62 -07 39 15.8 S 932
2021-03-06 00:24:05 S 09 25 46.997 -07 49 10.42 V C57
2021-03-06 00:24:05 s 1 -170880.41 5 +43910.578 360.0 C57
2021-03-06 00:27:12 C 09 26 43.79 -07 38 58.3 q G07
2021-03-06 00:34:05 S 09 25 44.762 -07 48 48.96 V C57
2021-03-06 00:34:05 s 1 -170487.75 3 +43001.999 9440.0 C57
2021-03-06 00:34:18 C 09 26 47.18 -07 38 41.2 S 932
2021-03-06 00:44:05 S 09 25 42.516 -07 48 27.04 V C57
2021-03-06 00:44:05 s 1 -170090.81 5 +42092.346 310.0 C57
2021-03-06 00:51:56 C 09 26 43.70 -07 38 07.1 S 932
2021-03-06 00:54:05 S 09 25 40.286 -07 48 04.25 V C57
2021-03-06 00:54:05 s 1 -169689.56 6 +41181.629 2920.0 C57
2021-03-06 01:02:38 C 09 26 40.92 -07 37 49.6 V I22
2021-03-06 01:03:07 C 09 26 40.83 -07 37 48.7 V I22
2021-03-06 01:03:38 C 09 26 40.72 -07 37 47.7 V I22
2021-03-06 01:04:05 S 09 25 38.030 -07 47 42.54 V C57
2021-03-06 01:04:05 s 1 -169283.97 4 +40269.861 7180.0 C57
2021-03-06 01:04:07 C 09 26 40.62 -07 37 46.7 V I22
2021-03-06 01:04:36 C 09 26 40.53 -07 37 45.8 V I22
2021-03-06 01:05:06 C 09 26 40.43 -07 37 44.8 V I22
2021-03-06 01:05:36 C 09 26 40.34 -07 37 43.9 V I22
2021-03-06 01:06:05 C 09 26 40.24 -07 37 42.8 V I22
2021-03-06 01:06:35 C 09 26 40.14 -07 37 41.9 V I22
2021-03-06 01:07:05 C 09 26 40.04 -07 37 40.9 V I22
2021-03-06 01:07:33 C 09 26 39.94 -07 37 40.1 V I22
2021-03-06 01:08:04 C 09 26 39.83 -07 37 38.8 V I22
2021-03-06 01:08:32 C 09 26 39.74 -07 37 37.9 V I22
2021-03-06 01:09:02 C 09 26 39.62 -07 37 36.9 V I22
2021-03-06 01:09:32 C 09 26 39.56 -07 37 36.1 V I22
2021-03-06 01:10:03 C 09 26 39.45 -07 37 35.2 V I22
2021-03-06 01:10:31 C 09 26 39.34 -07 37 34.3 V I22
2021-03-06 01:11:02 C 09 26 39.25 -07 37 33.2 V I22
2021-03-06 01:11:32 C 09 26 39.17 -07 37 32.2 V I22
2021-03-06 01:12:01 C 09 26 39.07 -07 37 31.2 V I22
2021-03-06 01:12:31 C 09 26 38.98 -07 37 30.3 V I22
2021-03-06 01:13:01 C 09 26 38.86 -07 37 29.3 V I22
2021-03-06 01:13:30 C 09 26 38.77 -07 37 28.4 V I22
2021-03-06 01:14:00 C 09 26 38.66 -07 37 27.4 V I22
2021-03-06 01:14:05 S 09 25 35.832 -07 47 20.04 V C57
2021-03-06 01:14:05 s 1 -168874.00 2 +39357.055 3040.0 C57
2021-03-06 01:14:30 C 09 26 38.58 -07 37 26.4 V I22
2021-03-06 01:14:59 C 09 26 38.47 -07 37 25.4 V I22
2021-03-06 01:15:29 C 09 26 38.38 -07 37 24.6 V I22
2021-03-06 01:15:59 C 09 26 38.28 -07 37 23.6 V I22
2021-03-06 01:16:27 C 09 26 38.18 -07 37 22.7 V I22
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)