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
2021-03-03 23:34:05 S 09 37 15.835 -09 28 56.21 V C57
2021-03-03 23:34:05 s 1 -180900.30 2 +252358.07 4310.0 C57
2021-03-03 23:36:32 C 09 35 53.67 -09 13 08.8 t Z21
2021-03-03 23:36:56 C 09 35 53.58 -09 13 08.0 t Z17
2021-03-03 23:39:12 C 09 35 50.34 -09 11 44.2 t L09
2021-03-03 23:41:28 C 09 35 52.62 -09 12 59.4 t Z17
2021-03-03 23:43:15 C 09 35 49.50 -09 11 36.5 t L09
2021-03-03 23:44:05 S 09 37 13.445 -09 28 37.16 V C57
2021-03-03 23:44:05 s 1 -181074.23 5 +251836.80 3800.0 C57
2021-03-03 23:44:45 C 09 35 51.94 -09 12 53.2 t Z21
2021-03-03 23:47:17 C 09 35 48.67 -09 11 28.6 t L09
2021-03-03 23:49:35 C 09 35 50.92 -09 12 44.0 t Z17
2021-03-03 23:51:20 C 09 35 47.84 -09 11 20.8 t L09
2021-03-03 23:54:05 S 09 37 11.155 -09 28 16.90 V C57
2021-03-03 23:54:05 s 1 -181247.31 0 +251314.34 1760.0 C57
2021-03-04 00:04:05 S 09 37 08.717 -09 27 58.25 V C57
2021-03-04 00:04:05 s 1 -181419.52 6 +250790.69 8180.0 C57
2021-03-04 00:14:05 S 09 37 06.374 -09 27 39.71 V C57
2021-03-04 00:14:05 s 1 -181590.87 8 +250265.85 3050.0 C57
2021-03-04 00:24:05 S 09 37 03.982 -09 27 20.70 V C57
2021-03-04 00:24:05 s 1 -181761.36 3 +249739.81 6360.0 C57
2021-03-04 00:34:05 S 09 37 01.654 -09 27 01.01 V C57
2021-03-04 00:34:05 s 1 -181930.97 8 +249212.59 8110.0 C57
2021-03-04 00:44:05 S 09 36 59.234 -09 26 41.32 V C57
2021-03-04 00:44:05 s 1 -182099.71 8 +248684.17 8290.0 C57
2021-03-04 00:54:05 S 09 36 56.873 -09 26 22.27 V C57
2021-03-04 00:54:05 s 1 -182267.58 1 +248154.55 6890.0 C57
2021-03-04 01:04:05 S 09 36 54.475 -09 26 04.27 V C57
2021-03-04 01:04:05 s 1 -182434.56 3 +247623.73 3910.0 C57
2021-03-04 01:12:05 C 09 35 38.19 -09 10 12.0 V W46
2021-03-04 01:14:05 S 09 36 52.152 -09 25 44.44 V C57
2021-03-04 01:14:05 s 1 -182600.66 0 +247091.72 9350.0 C57
2021-03-04 01:24:05 S 09 36 49.781 -09 25 25.00 V C57
2021-03-04 01:24:05 s 1 -182765.86 9 +246558.51 3190.0 C57
2021-03-04 01:34:05 S 09 36 47.405 -09 25 05.84 V C57
2021-03-04 01:34:05 s 1 -182930.18 7 +246024.10 5420.0 C57
2021-03-04 01:36:04 C 09 35 33.32 -09 09 27.2 V W46
2021-03-04 01:44:05 S 09 36 45.034 -09 24 47.02 V C57
2021-03-04 01:44:05 s 1 -183093.60 8 +245488.48 6050.0 C57
2021-03-04 01:54:05 S 09 36 42.650 -09 24 28.30 V C57
2021-03-04 01:54:05 s 1 -183256.13 1 +244951.66 5050.0 C57
2021-03-04 02:04:05 S 09 36 40.250 -09 24 07.78 V C57
2021-03-04 02:04:05 s 1 -183417.75 1 +244413.64 2440.0 C57
2021-03-04 02:05:47 C 09 35 27.37 -09 08 31.2 V W34
2021-03-04 02:10:07 C 09 35 26.34 -09 08 23.8 V W46
2021-03-04 02:14:05 S 09 36 37.886 -09 23 48.55 V C57
2021-03-04 02:14:05 s 1 -183578.46 5 +243874.41 8190.0 C57
2021-03-04 02:20:05 C 09 35 24.42 -09 08 04.2 V W34
2021-03-04 02:24:05 S 09 36 35.489 -09 23 29.98 V C57
2021-03-04 02:24:05 s 1 -183738.26 8 +243333.98 2310.0 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)