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
2021-01-13 04:51:04 C 11 44 08.696 -16 46 43.56 V Z84
2021-01-13 05:18:39 C 11 44 08.402 -16 46 57.69 V Z84
2021-01-13 05:46:14 C 11 44 08.130 -16 47 11.71 V Z84
2021-01-13 12:33:17 C 11 44 09.99 -16 50 32.3 V T08
2021-01-13 12:39:15 C 11 44 09.90 -16 50 35.6 V T08
2021-01-13 12:51:13 C 11 44 09.77 -16 50 41.9 V T08
2021-01-13 13:05:49 C 11 44 09.58 -16 50 49.5 V T08
2021-01-15 13:22:42 C 11 43 57.24 -17 15 08.9 V T05
2021-01-15 13:26:40 C 11 43 57.16 -17 15 10.8 V T05
2021-01-15 13:31:56 C 11 43 57.06 -17 15 13.4 V T05
2021-01-15 13:43:18 C 11 43 56.85 -17 15 19.2 V T05
2021-01-16 08:54:21 C 11 43 48.24 -17 24 42.9 V 703
2021-01-16 09:02:18 C 11 43 48.12 -17 24 46.2 V 703
2021-01-16 09:10:15 C 11 43 47.94 -17 24 50.3 V 703
2021-01-16 09:18:12 C 11 43 47.79 -17 24 55.1 V 703
2021-01-16 18:06:27 S 11 43 41.97 -17 27 49.0 L C53
2021-01-16 18:16:27 S 11 43 40.43 -17 27 57.0 L C53
2021-01-16 18:26:27 S 11 43 39.02 -17 28 22.1 L C53
2021-01-16 18:40:27 S 11 43 38.60 -17 29 10.1 L C53
2021-01-16 21:29:19 S 11 43 39.41 -17 29 25.5 L C53
2021-01-16 21:39:19 S 11 43 37.86 -17 29 36.5 L C53
2021-01-16 21:49:19 S 11 43 36.62 -17 30 02.6 L C53
2021-01-16 21:59:19 S 11 43 36.41 -17 30 37.9 L C53
2021-01-16 22:09:20 S 11 43 36.72 -17 31 06.2 L C53
2021-01-17 00:48:08 S 11 43 37.54 -17 30 59.6 L C53
2021-01-17 00:58:07 S 11 43 35.95 -17 31 07.3 L C53
2021-01-17 01:08:08 S 11 43 34.41 -17 31 27.9 L C53
2021-01-17 12:34:07 C 11 43 26.78 -17 37 48.8 V H06
2021-01-17 12:37:58 C 11 43 26.69 -17 37 50.4 V H06
2021-01-17 12:43:06 C 11 43 26.56 -17 37 52.6 V H06
2021-01-17 13:16:58 C 11 43 28.04 -17 38 01.5 V T08
2021-01-17 13:22:17 C 11 43 27.91 -17 38 04.0 V T08
2021-01-17 13:31:26 C 11 43 27.66 -17 38 08.3 V T08
2021-01-17 13:39:24 C 11 43 27.44 -17 38 12.0 V T08
2021-01-18 17:26:00 C 11 43 02.30 -17 51 01.3 q Q21
2021-01-18 17:35:38 C 11 43 02.11 -17 51 04.5 q Q21
2021-01-18 17:41:40 C 11 43 01.91 -17 51 06.8 q Q21
2021-01-18 18:17:58 C 11 43 00.88 -17 51 23.4 q Q21
2021-01-18 18:25:31 C 11 43 00.71 -17 51 28.0 q Q21
2021-01-18 18:33:04 C 11 43 00.47 -17 51 29.1 q Q21
2021-01-19 02:02:02 C 11 42 53.12 -17 54 51.1 V K83
2021-01-19 02:05:10 C 11 42 53.03 -17 54 53.0 V K83
2021-01-19 02:09:23 C 11 42 52.87 -17 54 55.5 V K83
2021-01-19 02:31:26 C 11 42 52.24 -17 55 04.5 V K83
2021-01-19 02:37:45 C 11 42 52.12 -17 55 07.7 V K83
2021-01-19 02:44:00 C 11 42 52.14 -17 55 10.2 U 511
2021-01-19 02:47:03 C 11 42 52.05 -17 55 11.6 U 511
2021-01-19 02:50:06 C 11 42 51.95 -17 55 12.9 U 511
2021-01-19 02:59:58 C 11 42 51.69 -17 55 17.0 U 511
2021-01-19 03:03:00 C 11 42 51.61 -17 55 18.6 U 511
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)