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
2021-02-23 19:34:05 s 1 +157749.60 1 +111465.91 9530.0 C57
2021-02-23 19:44:05 S 10 15 56.263 -14 27 28.98 V C57
2021-02-23 19:44:05 s 1 +157808.18 2 +112388.41 8370.0 C57
2021-02-23 19:54:05 S 10 15 55.082 -14 27 16.09 V C57
2021-02-23 19:54:05 s 1 +157863.76 5 +113308.77 1290.0 C57
2021-02-23 20:04:05 S 10 15 53.822 -14 27 03.49 V C57
2021-02-23 20:04:05 s 1 +157916.37 4 +114226.98 8350.0 C57
2021-02-23 20:14:05 S 10 15 52.685 -14 26 50.68 V C57
2021-02-23 20:14:05 s 1 +157966.03 5 +115143.05 9590.0 C57
2021-02-23 20:24:05 S 10 15 51.434 -14 26 37.54 V C57
2021-02-23 20:24:05 s 1 +158012.77 2 +116056.99 5070.0 C57
2021-02-23 20:34:05 S 10 15 50.177 -14 26 24.36 V C57
2021-02-23 20:34:05 s 1 +158056.61 0 +116968.79 4820.0 C57
2021-02-23 20:44:05 S 10 15 48.950 -14 26 11.80 V C57
2021-02-23 20:44:05 s 1 +158097.57 2 +117878.46 8890.0 C57
2021-02-23 20:54:05 S 10 15 47.729 -14 25 58.84 V C57
2021-02-23 20:54:05 s 1 +158135.68 2 +118785.99 7340.0 C57
2021-02-23 21:04:05 S 10 15 46.565 -14 25 46.49 V C57
2021-02-23 21:04:05 s 1 +158170.96 4 +119691.39 200.0 C57
2021-02-23 21:14:05 S 10 15 45.331 -14 25 33.85 V C57
2021-02-23 21:14:05 s 1 +158203.44 1 +120594.66 7520.0 C57
2021-02-23 21:24:05 S 10 15 44.066 -14 25 21.14 V C57
2021-02-23 21:24:05 s 1 +158233.13 7 +121495.80 9350.0 C57
2021-02-23 21:34:05 S 10 15 42.790 -14 25 08.18 V C57
2021-02-23 21:34:05 s 1 +158260.07 3 +122394.82 5730.0 C57
2021-02-23 21:44:05 S 10 15 41.599 -14 24 55.62 V C57
2021-02-23 21:44:05 s 1 +158284.27 3 +123291.72 6690.0 C57
2021-02-23 21:49:01 C 10 13 17.08 -14 35 59.3 V L06
2021-02-23 22:01:48 C 10 13 14.47 -14 35 42.4 V L06
2021-02-23 22:14:05 S 10 15 37.831 -14 24 16.38 V C57
2021-02-23 22:14:05 s 1 +158340.67 5 +125969.69 7580.0 C57
2021-02-23 22:14:35 C 10 13 11.87 -14 35 24.5 V L06
2021-02-23 22:24:05 S 10 15 36.607 -14 24 03.96 V C57
2021-02-23 22:24:05 s 1 +158354.14 9 +126858.11 7340.0 C57
2021-02-23 23:14:05 S 10 15 30.348 -14 22 58.98 V C57
2021-02-23 23:14:05 s 1 +158382.52 7 +131268.61 8990.0 C57
2021-02-23 23:24:05 S 10 15 29.047 -14 22 48.40 V C57
2021-02-23 23:24:05 s 1 +158380.54 9 +132144.40 8170.0 C57
2021-02-24 00:14:05 S 10 15 22.778 -14 21 43.60 V C57
2021-02-24 00:14:05 s 1 +158333.48 9 +136491.98 420.0 C57
2021-02-24 00:24:05 S 10 15 21.444 -14 21 30.06 V C57
2021-02-24 00:24:05 s 1 +158316.77 9 +137355.24 410.0 C57
2021-02-24 00:34:05 S 10 15 20.237 -14 21 17.42 V C57
2021-02-24 00:34:05 s 1 +158297.68 0 +138216.42 5660.0 C57
2021-02-24 00:44:05 S 10 15 18.924 -14 21 05.15 V C57
2021-02-24 00:44:05 s 1 +158276.21 2 +139075.52 6210.0 C57
2021-02-24 00:54:05 S 10 15 17.640 -14 20 52.12 V C57
2021-02-24 00:54:05 s 1 +158252.39 3 +139932.55 2090.0 C57
2021-02-24 01:04:05 S 10 15 16.394 -14 20 39.59 V C57
2021-02-24 01:04:05 s 1 +158226.24 0 +140787.51 3350.0 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)