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
2021-02-25 18:14:05 s 1 +108512.42 0 +297049.88 4920.0 C57
2021-02-25 18:24:05 S 10 08 56.873 -13 27 37.40 V C57
2021-02-25 18:24:05 s 1 +108206.44 1 +297490.63 9590.0 C57
2021-02-25 19:04:05 S 10 08 50.102 -13 26 46.90 V C57
2021-02-25 19:04:05 s 1 +106977.67 3 +299240.16 8030.0 C57
2021-02-25 19:28:37 C 10 04 29.54 -13 29 28.6 q 168
2021-02-25 19:50:38 C 10 04 25.01 -13 28 55.1 q 168
2021-02-25 20:02:37 C 10 04 22.55 -13 28 36.6 q 168
2021-02-25 20:14:37 C 10 04 20.07 -13 28 18.1 q 168
2021-02-25 20:24:05 S 10 08 35.930 -13 24 57.49 V C57
2021-02-25 20:24:05 s 1 +104497.42 8 +302674.96 6930.0 C57
2021-02-25 20:24:38 C 10 04 18.02 -13 28 02.7 q 168
2021-02-25 20:34:05 S 10 08 34.253 -13 24 44.21 V C57
2021-02-25 20:34:05 s 1 +104185.32 1 +303098.32 8650.0 C57
2021-02-25 20:44:05 S 10 08 32.489 -13 24 31.28 V C57
2021-02-25 20:44:05 s 1 +103872.76 1 +303520.35 9400.0 C57
2021-02-25 20:54:05 S 10 08 30.725 -13 24 18.54 V C57
2021-02-25 20:54:05 s 1 +103559.75 0 +303941.06 9200.0 C57
2021-02-25 21:31:48 C 10 04 06.45 -13 26 14.7 V 118
2021-02-25 22:02:40 C 10 04 00.05 -13 25 27.9 V 118
2021-02-25 22:32:17 C 10 03 54.25 -13 24 39.1 V 160
2021-02-25 22:33:08 C 10 03 53.67 -13 24 40.7 V 118
2021-02-25 22:36:56 C 10 03 53.29 -13 24 32.0 V 160
2021-02-25 22:41:35 C 10 03 52.31 -13 24 24.8 V 160
2021-02-25 22:54:05 S 10 08 09.871 -13 21 41.44 V C57
2021-02-25 22:54:05 s 1 +99769.439 0 +308887.01 4190.0 C57
2021-02-25 23:04:05 S 10 08 07.877 -13 21 24.34 V C57
2021-02-25 23:04:05 s 1 +99450.806 0 +309290.67 2030.0 C57
2021-02-25 23:14:05 S 10 08 06.130 -13 21 11.30 V C57
2021-02-25 23:14:05 s 1 +99131.759 0 +309693.04 8990.0 C57
2021-02-25 23:24:05 S 10 08 04.354 -13 20 57.59 V C57
2021-02-25 23:24:05 s 1 +98812.298 0 +310094.10 5070.0 C57
2021-02-25 23:34:57 C 10 03 41.81 -13 23 08.6 V Z99
2021-02-25 23:38:49 C 10 03 41.02 -13 23 02.4 V Z99
2021-02-25 23:42:42 C 10 03 40.20 -13 22 56.7 V Z99
2021-02-25 23:44:05 S 10 08 00.950 -13 20 30.88 V C57
2021-02-25 23:44:05 s 1 +98172.149 0 +310892.35 4600.0 C57
2021-02-25 23:46:40 C 10 03 39.39 -13 22 50.6 V Z99
2021-02-25 23:50:44 C 10 03 38.53 -13 22 44.1 V Z99
2021-02-25 23:54:37 C 10 03 37.72 -13 22 38.3 V Z99
2021-02-25 23:58:29 C 10 03 36.92 -13 22 32.2 V Z99
2021-02-26 00:02:22 C 10 03 36.11 -13 22 26.3 V Z99
2021-02-26 01:33:36 C 10 03 20.89 -13 18 26.7 q 834
2021-02-26 02:01:37 C 10 03 14.99 -13 17 43.6 q 834
2021-02-26 12:24:05 S 10 05 42.878 -13 03 17.57 V C57
2021-02-26 12:24:05 s 1 +72802.724 0 +337504.11 640.0 C57
2021-02-26 12:34:05 S 10 05 41.018 -13 03 03.46 V C57
2021-02-26 12:34:05 s 1 +72457.383 0 +337807.34 400.0 C57
2021-02-26 12:44:05 S 10 05 39.173 -13 02 48.80 V C57
2021-02-26 12:44:05 s 1 +72111.791 0 +338109.40 9600.0 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)