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 08:44:05 S 09 56 53.712 -11 58 30.79 V C57
2021-02-28 08:44:05 s 1 -23651.406 0 +379242.02 8910.0 C57
2021-02-28 08:54:05 S 09 56 51.643 -11 58 14.30 V C57
2021-02-28 08:54:05 s 1 -24017.549 0 +379259.57 9390.0 C57
2021-02-28 09:04:05 S 09 56 49.550 -11 57 58.46 V C57
2021-02-28 09:04:05 s 1 -24383.626 0 +379276.13 9820.0 C57
2021-02-28 09:14:05 S 09 56 47.414 -11 57 43.34 V C57
2021-02-28 09:14:05 s 1 -24749.638 0 +379291.69 190.0 C57
2021-02-28 09:24:05 S 09 56 45.336 -11 57 28.69 V C57
2021-02-28 09:24:05 s 1 -25115.582 0 +379306.24 520.0 C57
2021-02-28 09:34:05 S 09 56 43.210 -11 57 13.72 V C57
2021-02-28 09:34:05 s 1 -25481.459 0 +379319.80 790.0 C57
2021-02-28 09:44:05 S 09 56 41.059 -11 56 57.98 V C57
2021-02-28 09:44:05 s 1 -25847.267 0 +379332.35 1010.0 C57
2021-02-28 09:54:05 S 09 56 39.012 -11 56 41.78 V C57
2021-02-28 09:54:05 s 1 -26213.005 0 +379343.91 1170.0 C57
2021-02-28 10:04:05 S 09 56 36.900 -11 56 25.76 V C57
2021-02-28 10:04:05 s 1 -26578.672 0 +379354.46 1270.0 C57
2021-02-28 10:14:05 S 09 56 34.776 -11 56 10.43 V C57
2021-02-28 10:14:05 s 1 -26944.267 0 +379364.02 1310.0 C57
2021-02-28 10:24:05 S 09 56 32.652 -11 55 55.81 V C57
2021-02-28 10:24:05 s 1 -27309.790 0 +379372.57 1290.0 C57
2021-02-28 10:34:05 S 09 56 30.499 -11 55 40.62 V C57
2021-02-28 10:34:05 s 1 -27675.240 0 +379380.13 1200.0 C57
2021-02-28 10:44:05 S 09 56 28.406 -11 55 24.89 V C57
2021-02-28 10:44:05 s 1 -28040.615 0 +379386.69 1050.0 C57
2021-02-28 10:54:05 S 09 56 26.335 -11 55 08.33 V C57
2021-02-28 10:54:05 s 1 -28405.914 0 +379392.25 830.0 C57
2021-02-28 11:04:05 S 09 56 24.223 -11 54 52.74 V C57
2021-02-28 11:04:05 s 1 -28771.137 0 +379396.82 540.0 C57
2021-02-28 11:14:05 S 09 56 22.085 -11 54 37.51 V C57
2021-02-28 11:14:05 s 1 -29136.283 0 +379400.38 180.0 C57
2021-02-28 11:24:05 S 09 56 19.970 -11 54 22.68 V C57
2021-02-28 11:24:05 s 1 -29501.350 0 +379402.95 9740.0 C57
2021-02-28 11:34:05 S 09 56 17.815 -11 54 07.24 V C57
2021-02-28 11:34:05 s 1 -29866.338 0 +379404.52 9240.0 C57
2021-02-28 11:44:05 S 09 56 15.703 -11 53 51.50 V C57
2021-02-28 11:44:05 s 1 -30231.246 0 +379405.09 8650.0 C57
2021-02-28 11:54:05 S 09 56 13.598 -11 53 34.62 V C57
2021-02-28 11:54:05 s 1 -30596.073 0 +379404.67 7990.0 C57
2021-02-28 12:04:05 S 09 56 11.494 -11 53 19.50 V C57
2021-02-28 12:04:05 s 1 -30960.818 0 +379403.25 7240.0 C57
2021-02-28 12:14:05 S 09 56 09.422 -11 53 04.60 V C57
2021-02-28 12:14:05 s 1 -31325.480 0 +379400.84 6420.0 C57
2021-02-28 12:24:05 S 09 56 07.298 -11 52 49.04 V C57
2021-02-28 12:24:05 s 1 -31690.059 0 +379397.43 5510.0 C57
2021-02-28 12:34:05 S 09 56 05.126 -11 52 34.07 V C57
2021-02-28 12:34:05 s 1 -32054.552 0 +379393.02 4520.0 C57
2021-02-28 12:44:05 S 09 56 03.022 -11 52 17.65 V C57
2021-02-28 12:44:05 s 1 -32418.960 0 +379387.62 3440.0 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)