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
2021-02-28 21:54:05 S 09 54 05.136 -11 37 48.50 V C57
2021-02-28 21:54:05 s 1 -52302.011 0 +377563.58 8830.0 C57
2021-02-28 22:04:05 S 09 54 03.005 -11 37 33.28 V C57
2021-02-28 22:04:05 s 1 -52660.127 0 +377502.74 90.0 C57
2021-02-28 22:14:05 S 09 54 00.838 -11 37 17.94 V C57
2021-02-28 22:14:05 s 1 -53018.103 0 +377440.92 1160.0 C57
2021-02-28 22:21:11 C 09 49 57.30 -11 26 47.4 V 118
2021-02-28 22:24:05 S 09 53 58.610 -11 37 01.49 V C57
2021-02-28 22:24:05 s 1 -53375.940 0 +377378.12 2040.0 C57
2021-02-28 22:34:05 S 09 53 56.515 -11 36 44.78 V C57
2021-02-28 22:34:05 s 1 -53733.635 0 +377314.33 2730.0 C57
2021-02-28 22:37:47 C 09 49 53.83 -11 26 18.3 V 118
2021-02-28 22:41:03 C 09 49 54.19 -11 26 14.6 V Z80
2021-02-28 22:44:05 S 09 53 54.365 -11 36 28.33 V C57
2021-02-28 22:44:05 s 1 -54091.189 0 +377249.55 3230.0 C57
2021-02-28 22:45:12 C 09 49 53.33 -11 26 07.7 V Z80
2021-02-28 22:49:23 C 09 49 52.46 -11 26 00.1 V Z80
2021-02-28 22:53:32 C 09 49 51.60 -11 25 53.1 V Z80
2021-02-28 22:54:05 S 09 53 52.140 -11 36 12.92 V C57
2021-02-28 22:54:05 s 1 -54448.600 0 +377183.79 3540.0 C57
2021-02-28 22:54:23 C 09 49 50.36 -11 25 49.3 V 118
2021-02-28 23:04:05 S 09 53 50.004 -11 35 57.37 V C57
2021-02-28 23:04:05 s 1 -54805.867 0 +377117.04 3650.0 C57
2021-02-28 23:14:05 S 09 53 47.810 -11 35 41.78 V C57
2021-02-28 23:14:05 s 1 -55162.989 0 +377049.31 3560.0 C57
2021-02-28 23:24:05 S 09 53 45.626 -11 35 25.51 V C57
2021-02-28 23:24:05 s 1 -55519.966 0 +376980.59 3280.0 C57
2021-02-28 23:34:05 S 09 53 43.495 -11 35 08.34 V C57
2021-02-28 23:34:05 s 1 -55876.797 0 +376910.89 2790.0 C57
2021-02-28 23:44:05 S 09 53 41.376 -11 34 52.46 V C57
2021-02-28 23:44:05 s 1 -56233.479 0 +376840.20 2100.0 C57
2021-02-28 23:54:05 S 09 53 39.182 -11 34 38.06 V C57
2021-02-28 23:54:05 s 1 -56590.014 0 +376768.53 1210.0 C57
2021-03-01 00:04:05 S 09 53 36.962 -11 34 21.47 V C57
2021-03-01 00:04:05 s 1 -56946.399 0 +376695.88 110.0 C57
2021-03-01 00:14:05 S 09 53 34.814 -11 34 06.13 V C57
2021-03-01 00:14:05 s 1 -57302.633 0 +376622.24 8810.0 C57
2021-03-01 00:24:05 S 09 53 32.635 -11 33 48.92 V C57
2021-03-01 00:24:05 s 1 -57658.716 0 +376547.61 7290.0 C57
2021-03-01 00:34:05 S 09 53 30.446 -11 33 31.61 V C57
2021-03-01 00:34:05 s 1 -58014.647 0 +376472.00 5560.0 C57
2021-03-01 00:44:05 S 09 53 28.301 -11 33 16.06 V C57
2021-03-01 00:44:05 s 1 -58370.425 0 +376395.41 3620.0 C57
2021-03-01 00:54:05 S 09 53 26.155 -11 33 00.79 V C57
2021-03-01 00:54:05 s 1 -58726.049 0 +376317.83 1470.0 C57
2021-03-01 01:04:05 S 09 53 23.914 -11 32 44.74 V C57
2021-03-01 01:04:05 s 1 -59081.518 0 +376239.27 9090.0 C57
2021-03-01 01:14:05 S 09 53 21.746 -11 32 29.11 V C57
2021-03-01 01:14:05 s 1 -59436.830 0 +376159.72 6500.0 C57
2021-03-01 01:24:05 S 09 53 19.608 -11 32 12.62 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)