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
2021-02-27 23:24:11 C 09 54 24.84 -12 06 02.1 V Z80
2021-02-27 23:29:11 C 09 54 23.83 -12 05 53.4 V Z80
2021-02-27 23:34:05 S 09 58 48.298 -12 12 30.53 V C57
2021-02-27 23:34:11 C 09 54 22.79 -12 05 45.0 V Z80
2021-02-27 23:44:05 S 09 58 46.217 -12 12 16.20 V C57
2021-02-27 23:54:05 S 09 58 44.174 -12 12 00.50 V C57
2021-02-27 23:59:33 C 09 54 17.50 -12 05 03.9 V Z99
2021-02-28 00:03:12 C 09 54 16.75 -12 04 57.6 V Z99
2021-02-28 00:04:05 S 09 58 42.106 -12 11 44.41 V C57
2021-02-28 00:06:51 C 09 54 15.97 -12 04 51.5 V Z99
2021-02-28 00:10:31 C 09 54 15.23 -12 04 45.4 V Z99
2021-02-28 00:14:05 S 09 58 40.066 -12 11 29.83 V C57
2021-02-28 00:14:09 C 09 54 14.45 -12 04 39.1 V Z99
2021-02-28 00:24:05 S 09 58 37.987 -12 11 14.68 V C57
2021-02-28 00:34:05 S 09 58 35.940 -12 11 00.67 V C57
2021-02-28 00:44:05 S 09 58 33.878 -12 10 45.37 V C57
2021-02-28 00:54:05 S 09 58 31.754 -12 10 29.42 V C57
2021-02-28 01:04:05 S 09 58 29.731 -12 10 13.87 V C57
2021-02-28 01:14:05 S 09 58 27.650 -12 09 58.28 V C57
2021-02-28 01:24:05 S 09 58 25.598 -12 09 45.29 V C57
2021-02-28 01:34:05 S 09 58 23.537 -12 09 28.84 V C57
2021-02-28 01:44:05 S 09 58 21.398 -12 09 13.97 V C57
2021-02-28 01:54:05 S 09 58 19.361 -12 08 58.45 V C57
2021-02-28 02:04:05 S 09 58 17.335 -12 08 42.43 V C57
2021-02-28 02:14:05 S 09 58 15.211 -12 08 27.49 V C57
2021-02-28 02:24:05 S 09 58 13.164 -12 08 12.73 V C57
2021-02-28 02:34:05 S 09 58 11.047 -12 07 57.68 V C57
2021-02-28 02:34:05 s 1 -10067.041 0 +377885.55 6210.0 C57
2021-02-28 02:44:05 S 09 58 09.017 -12 07 43.68 V C57
2021-02-28 02:44:05 s 1 -10434.923 0 +377940.39 5210.0 C57
2021-02-28 02:54:05 S 09 58 06.919 -12 07 27.23 V C57
2021-02-28 02:54:05 s 1 -10802.776 0 +377994.21 4200.0 C57
2021-02-28 03:04:05 S 09 58 04.848 -12 07 11.03 V C57
2021-02-28 03:04:05 s 1 -11170.598 0 +378047.02 3160.0 C57
2021-02-28 03:14:05 S 09 58 02.810 -12 06 55.94 V C57
2021-02-28 03:14:05 s 1 -11538.389 0 +378098.81 2120.0 C57
2021-02-28 03:24:05 S 09 58 00.682 -12 06 41.54 V C57
2021-02-28 03:24:05 s 1 -11906.146 0 +378149.59 1050.0 C57
2021-02-28 03:34:05 S 09 57 58.627 -12 06 26.86 V C57
2021-02-28 03:34:05 s 1 -12273.870 0 +378199.36 9980.0 C57
2021-02-28 03:44:05 S 09 57 56.544 -12 06 11.99 V C57
2021-02-28 03:44:05 s 1 -12641.560 0 +378248.12 8900.0 C57
2021-02-28 03:54:05 S 09 57 54.437 -12 05 55.68 V C57
2021-02-28 03:54:05 s 1 -13009.214 0 +378295.86 7810.0 C57
2021-02-28 04:04:05 S 09 57 52.387 -12 05 39.52 V C57
2021-02-28 04:04:05 s 1 -13376.831 0 +378342.60 6720.0 C57
2021-02-28 04:14:05 S 09 57 50.292 -12 05 24.90 V C57
2021-02-28 04:14:05 s 1 -13744.411 0 +378388.32 5620.0 C57
2021-02-28 04:24:05 S 09 57 48.185 -12 05 09.60 V C57
2021-02-28 04:24:05 s 1 -14111.953 0 +378433.03 4520.0 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)