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 14:34:05 s 1 +149733.48 1 +203478.66 3510.0 C57
2021-02-24 14:44:05 S 10 13 23.191 -14 03 19.87 V C57
2021-02-24 14:44:05 s 1 +149563.88 6 +204175.65 7990.0 C57
2021-02-24 15:14:05 S 10 13 18.787 -14 02 43.33 V C57
2021-02-24 15:14:05 s 1 +149047.33 9 +206255.96 5770.0 C57
2021-02-24 15:24:05 S 10 13 17.302 -14 02 28.97 V C57
2021-02-24 15:24:05 s 1 +148872.59 8 +206945.85 9870.0 C57
2021-02-24 16:14:05 S 10 13 10.025 -14 01 26.69 V C57
2021-02-24 16:14:05 s 1 +147980.06 6 +210368.87 2320.0 C57
2021-02-24 16:24:05 S 10 13 08.450 -14 01 13.58 V C57
2021-02-24 16:24:05 s 1 +147797.85 0 +211048.21 1310.0 C57
2021-02-24 16:34:05 S 10 13 06.905 -14 01 01.16 V C57
2021-02-24 16:34:05 s 1 +147614.41 6 +211725.81 7840.0 C57
2021-02-24 16:44:05 S 10 13 05.366 -14 00 48.92 V C57
2021-02-24 16:44:05 s 1 +147429.77 2 +212401.66 1920.0 C57
2021-02-24 17:34:05 S 10 12 58.003 -13 59 44.12 V C57
2021-02-24 17:34:05 s 1 +146488.65 8 +215754.89 6110.0 C57
2021-02-24 17:44:05 S 10 12 56.486 -13 59 30.84 V C57
2021-02-24 17:44:05 s 1 +146296.91 0 +216420.35 5810.0 C57
2021-02-24 18:14:05 S 10 12 51.994 -13 58 53.83 V C57
2021-02-24 18:14:05 s 1 +145714.74 4 +218406.44 890.0 C57
2021-02-24 19:14:05 S 10 12 43.020 -13 57 38.38 V C57
2021-02-24 19:14:05 s 1 +144519.91 2 +222332.50 9210.0 C57
2021-02-24 19:44:05 S 10 12 38.309 -13 56 58.81 V C57
2021-02-24 19:44:05 s 1 +143907.62 1 +224272.66 3180.0 C57
2021-02-24 20:34:05 S 10 12 30.742 -13 55 58.80 V C57
2021-02-24 20:34:05 s 1 +142865.72 6 +227472.66 2980.0 C57
2021-02-24 21:12:50 C 10 08 48.07 -14 02 42.4 q 056
2021-02-24 21:17:34 C 10 08 47.31 -14 02 33.4 q 056
2021-02-24 21:22:20 C 10 08 46.16 -14 02 28.6 q 056
2021-02-24 21:27:05 C 10 08 45.15 -14 02 21.7 q 056
2021-02-24 21:31:50 C 10 08 44.11 -14 02 14.9 q 056
2021-02-24 21:32:41 C 10 08 44.64 -14 02 14.0 V G04
2021-02-24 21:34:49 C 10 08 44.15 -14 02 10.5 V G04
2021-02-24 21:36:56 C 10 08 43.72 -14 02 07.9 V G04
2021-02-24 21:38:08 C 10 08 44.12 -14 01 57.8 V K14
2021-02-24 21:39:04 C 10 08 43.31 -14 02 04.7 V G04
2021-02-24 21:41:11 C 10 08 42.90 -14 02 02.0 V G04
2021-02-24 21:42:08 C 10 08 42.65 -14 01 56.0 V G17
2021-02-24 21:43:18 C 10 08 42.44 -14 01 58.8 V G04
2021-02-24 21:44:48 C 10 08 42.11 -14 01 51.6 V G17
2021-02-24 21:45:25 C 10 08 42.01 -14 01 55.7 V G04
2021-02-24 21:47:28 C 10 08 41.54 -14 01 48.3 V G17
2021-02-24 21:52:35 C 10 08 41.11 -14 01 37.0 V K14
2021-02-24 22:04:05 S 10 12 16.922 -13 54 00.22 V C57
2021-02-24 22:04:05 s 1 +140925.16 8 +233127.92 4100.0 C57
2021-02-24 22:04:13 C 10 08 39.091 -14 01 17.82 V Z84
2021-02-24 22:07:20 C 10 08 38.04 -14 01 15.7 V K14
2021-02-24 22:14:05 S 10 12 15.365 -13 53 48.37 V C57
2021-02-24 22:14:05 s 1 +140704.53 6 +233748.04 5120.0 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)