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
2021-02-19 20:44:05 S 10 32 26.239 -16 54 09.83 V C57
2021-02-19 20:44:05 s 1 -200661.68 5 +180188.95 9850.0 C57
2021-02-19 20:54:05 S 10 32 24.019 -16 53 58.74 V C57
2021-02-19 20:54:05 s 1 -200690.18 9 +179521.79 3200.0 C57
2021-02-19 21:04:05 S 10 32 21.583 -16 53 47.04 V C57
2021-02-19 21:04:05 s 1 -200717.26 2 +178853.34 3900.0 C57
2021-02-19 21:14:05 S 10 32 19.274 -16 53 36.31 V C57
2021-02-19 21:14:05 s 1 -200742.89 8 +178183.61 1920.0 C57
2021-02-19 21:24:05 S 10 32 16.978 -16 53 25.40 V C57
2021-02-19 21:24:05 s 1 -200767.09 1 +177512.59 7260.0 C57
2021-02-19 21:34:05 S 10 32 14.681 -16 53 14.32 V C57
2021-02-19 21:34:05 s 1 -200789.83 2 +176840.28 9900.0 C57
2021-02-19 21:44:05 S 10 32 12.403 -16 53 02.65 V C57
2021-02-19 21:44:05 s 1 -200811.11 6 +176166.68 9820.0 C57
2021-02-19 21:54:05 S 10 32 10.070 -16 52 51.31 V C57
2021-02-19 21:54:05 s 1 -200830.93 5 +175491.78 7020.0 C57
2021-02-19 22:00:27 C 10 31 00.96 -16 33 28.8 c 095
2021-02-19 22:00:54 C 10 31 02.04 -16 33 27.4 L28
2021-02-19 22:01:01 C 10 31 00.86 -16 33 28.0 c 095
2021-02-19 22:01:34 C 10 31 00.74 -16 33 27.2 c 095
2021-02-19 22:01:51 C 10 31 00.70 -16 33 26.7 c 095
2021-02-19 22:01:58 C 10 31 01.83 -16 33 26.1 L28
2021-02-19 22:02:08 C 10 31 00.65 -16 33 26.4 c 095
2021-02-19 22:02:25 C 10 31 00.58 -16 33 26.5 c 095
2021-02-19 22:02:58 C 10 31 00.45 -16 33 25.6 c 095
2021-02-19 22:03:15 C 10 31 00.40 -16 33 25.0 c 095
2021-02-19 22:04:05 S 10 32 07.778 -16 52 40.66 V C57
2021-02-19 22:04:05 s 1 -200849.28 1 +174815.60 1470.0 C57
2021-02-19 22:04:07 C 10 31 01.44 -16 33 23.2 L28
2021-02-19 22:06:15 C 10 31 01.03 -16 33 21.0 L28
2021-02-19 22:08:23 C 10 31 00.61 -16 33 19.6 L28
2021-02-19 22:10:17 C 10 31 01.458 -16 33 09.17 V Z84
2021-02-19 22:11:34 C 10 30 59.96 -16 33 16.0 L28
2021-02-19 22:13:42 C 10 30 59.60 -16 33 14.1 L28
2021-02-19 22:14:05 S 10 32 05.453 -16 52 29.46 V C57
2021-02-19 22:14:05 s 1 -200866.14 9 +174138.12 3180.0 C57
2021-02-19 22:14:46 C 10 30 59.34 -16 33 12.6 L28
2021-02-19 22:16:54 C 10 30 58.95 -16 33 10.6 L28
2021-02-19 22:17:59 C 10 30 58.76 -16 33 09.0 L28
2021-02-19 22:24:05 S 10 32 03.173 -16 52 17.87 V C57
2021-02-19 22:24:05 s 1 -200881.53 0 +173459.35 2110.0 C57
2021-02-19 22:24:23 C 10 30 57.52 -16 33 02.8 L28
2021-02-19 22:26:30 C 10 30 57.09 -16 33 01.0 L28
2021-02-19 22:27:34 C 10 30 56.84 -16 32 59.2 L28
2021-02-19 22:29:42 C 10 30 56.49 -16 32 57.6 L28
2021-02-19 22:34:05 S 10 32 00.780 -16 52 06.28 V C57
2021-02-19 22:34:05 s 1 -200895.41 7 +172779.28 8260.0 C57
2021-02-19 22:35:03 C 10 30 55.41 -16 32 51.5 L28
2021-02-19 22:37:11 C 10 30 54.98 -16 32 50.5 L28
2021-02-19 22:44:05 S 10 31 58.507 -16 51 55.22 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)