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
2021-04-14 18:23:30 C 08 02 21.56 +17 20 27.2 q 168
2021-04-14 18:31:30 C 08 02 21.33 +17 20 35.1 q 168
2021-04-14 19:49:30 C 08 02 19.82 +17 21 49.4 q 168
2021-04-14 19:52:31 C 08 02 20.67 +17 22 09.8 Z K19
2021-04-14 20:05:51 C 08 02 20.30 +17 22 22.6 Z K19
2021-04-14 20:19:08 C 08 02 19.94 +17 22 35.6 Z K19
2021-04-14 21:00:28 C 08 02 19.34 +17 23 09.5 V Z80
2021-04-14 21:07:57 C 08 02 19.12 +17 23 17.4 V Z80
2021-04-15 06:01:00 C 08 02 10.84 +17 32 33.4 V T05
2021-04-15 06:15:39 C 08 02 10.37 +17 32 47.2 V T05
2021-04-15 06:24:57 C 08 02 10.08 +17 32 56.1 V T05
2021-04-15 06:29:33 C 08 02 09.94 +17 33 00.6 V T05
2021-04-15 17:02:30 C 08 02 00.03 +17 42 47.3 q 168
2021-04-15 18:30:29 C 08 01 58.09 +17 44 10.2 q 168
2021-04-15 18:32:30 C 08 01 58.06 +17 44 11.7 q 168
2021-04-15 19:44:34 C 08 01 57.45 +17 45 36.1 V 160
2021-04-15 19:48:47 C 08 01 57.34 +17 45 40.1 V 160
2021-04-15 19:53:25 C 08 01 57.23 +17 45 44.4 V 160
2021-04-15 20:56:05 C 08 01 56.31 +17 46 38.3 V Z80
2021-04-15 21:03:35 C 08 01 56.13 +17 46 46.2 V Z80
2021-04-16 20:57:13 C 08 01 35.07 +18 09 48.5 V Z80
2021-04-16 21:02:13 C 08 01 34.98 +18 09 53.4 V Z80
2021-04-16 21:07:13 C 08 01 34.83 +18 09 58.7 V Z80
2021-04-17 06:14:03 C 08 01 27.36 +18 19 10.7 V T08
2021-04-17 06:18:44 C 08 01 27.23 +18 19 14.9 V T08
2021-04-17 06:29:26 C 08 01 26.93 +18 19 24.9 V T08
2021-04-17 19:21:12 C 08 01 16.82 +18 31 01.4 o 069
2021-04-17 19:36:36 C 08 01 16.51 +18 31 15.5 o 069
2021-04-17 19:38:56 C 08 01 16.53 +18 31 29.2 V 160
2021-04-17 19:43:14 C 08 01 16.44 +18 31 33.2 V 160
2021-04-17 19:47:25 C 08 01 16.36 +18 31 36.8 V 160
2021-04-17 19:51:36 C 08 01 16.23 +18 31 29.2 o 069
2021-04-18 19:17:11 C 08 00 58.52 +18 53 25.0 o 069
2021-04-18 19:32:11 C 08 00 58.24 +18 53 38.5 o 069
2021-04-18 19:47:10 C 08 00 57.96 +18 53 51.8 o 069
2021-04-18 21:06:09 C 08 00 56.94 +18 55 09.5 V Z80
2021-04-18 21:11:08 C 08 00 56.78 +18 55 14.3 V Z80
2021-04-18 21:16:08 C 08 00 56.76 +18 55 18.9 V Z80
2021-04-18 21:21:13 C 08 00 56.64 +18 55 22.5 V Z80
2021-04-21 12:33:10 C 08 00 12.13 +19 53 11.7 q 900
2021-04-21 12:43:16 C 08 00 11.95 +19 53 20.4 q 900
2021-04-21 20:47:05 C 08 00 07.73 +20 00 22.5 V Z80
2021-04-21 20:53:45 C 08 00 07.54 +20 00 28.4 V Z80
2021-04-21 21:00:25 C 08 00 07.44 +20 00 34.8 V Z80
2021-04-22 19:44:46 C 07 59 52.60 +20 20 54.4 V 160
2021-04-22 19:48:23 C 07 59 52.52 +20 20 57.6 V 160
2021-04-22 19:52:00 C 07 59 52.45 +20 21 00.6 V 160
2021-04-22 20:51:33 C 07 59 51.96 +20 21 46.5 V Z80
2021-04-22 20:58:22 C 07 59 51.78 +20 21 52.7 V Z80
2021-04-22 21:05:27 C 07 59 51.67 +20 21 59.1 V Z80
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)