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
2021-01-21 07:37:23 C 11 41 40.34 -18 16 47.2 q Y00
2021-01-21 07:42:34 C 11 41 40.16 -18 16 49.2 q Y00
2021-01-21 07:46:27 C 11 41 40.04 -18 16 51.0 q Y00
2021-01-21 07:49:27 C 11 41 39.89 -18 16 51.8 q Y00
2021-01-21 07:51:35 C 11 41 39.82 -18 16 52.8 q Y00
2021-01-21 15:29:24 C 11 41 27.30 -18 20 25.0 V T08
2021-01-21 15:45:27 C 11 41 26.66 -18 20 30.9 V T08
2021-01-21 16:00:46 C 11 41 26.06 -18 20 36.6 V T08
2021-01-21 16:08:44 C 11 41 25.74 -18 20 39.4 V T08
2021-01-22 00:14:08 C 11 41 14.81 -18 24 04.9 V L54
2021-01-22 00:50:58 C 11 41 13.40 -18 24 19.6 V L54
2021-01-22 01:28:59 C 11 41 11.94 -18 24 35.2 V L54
2021-01-25 17:34:22 C 11 38 00.54 -18 55 28.0 q Q21
2021-01-25 17:37:22 C 11 38 00.36 -18 55 28.9 q Q21
2021-01-25 17:43:26 C 11 38 00.05 -18 55 30.9 q Q21
2021-01-26 19:50:37 C 11 36 48.99 -19 03 17.4 N42
2021-01-26 19:52:54 C 11 36 48.87 -19 03 18.2 N42
2021-01-26 19:55:11 C 11 36 48.73 -19 03 18.7 N42
2021-01-26 19:57:29 C 11 36 48.61 -19 03 19.5 N42
2021-01-26 19:59:46 C 11 36 48.46 -19 03 20.3 N42
2021-01-26 20:02:04 C 11 36 48.32 -19 03 21.0 N42
2021-01-26 20:04:21 C 11 36 48.17 -19 03 21.5 N42
2021-01-26 20:06:38 C 11 36 48.05 -19 03 22.4 N42
2021-01-26 20:08:56 C 11 36 47.94 -19 03 23.2 N42
2021-01-26 20:13:31 C 11 36 47.66 -19 03 24.6 N42
2021-01-26 20:15:47 C 11 36 47.51 -19 03 25.0 N42
2021-01-26 20:18:05 C 11 36 47.40 -19 03 25.9 N42
2021-01-26 20:22:39 C 11 36 47.12 -19 03 27.3 N42
2021-01-26 20:24:57 C 11 36 46.99 -19 03 28.0 N42
2021-01-26 20:27:14 C 11 36 46.87 -19 03 28.7 N42
2021-01-26 20:29:31 C 11 36 46.72 -19 03 29.4 N42
2021-01-26 20:31:49 C 11 36 46.55 -19 03 29.8 N42
2021-01-26 20:34:05 C 11 36 46.46 -19 03 30.8 N42
2021-01-26 20:36:23 C 11 36 46.31 -19 03 31.3 N42
2021-01-26 20:38:40 C 11 36 46.19 -19 03 32.2 N42
2021-01-26 22:01:03 C 11 36 41.25 -19 03 56.3 N42
2021-01-26 22:03:20 C 11 36 41.11 -19 03 56.7 N42
2021-01-26 22:05:38 C 11 36 40.99 -19 03 57.3 N42
2021-01-26 22:07:55 C 11 36 40.84 -19 03 57.9 N42
2021-01-26 22:12:29 C 11 36 40.58 -19 03 59.2 N42
2021-01-26 22:14:46 C 11 36 40.43 -19 03 59.9 N42
2021-01-26 22:17:04 C 11 36 40.29 -19 04 00.5 N42
2021-01-26 22:19:21 C 11 36 40.14 -19 04 01.1 N42
2021-01-26 22:21:38 C 11 36 40.01 -19 04 01.8 N42
2021-01-26 22:23:56 C 11 36 39.87 -19 04 02.5 N42
2021-01-27 00:12:57 C 11 36 36.15 -19 04 31.3 V G17
2021-01-27 00:18:18 C 11 36 35.83 -19 04 33.7 V G17
2021-01-27 00:23:38 C 11 36 35.50 -19 04 35.2 V G17
2021-01-28 19:57:12 C 11 34 15.66 -19 15 38.9 V 217
2021-01-28 19:58:20 C 11 34 15.58 -19 15 39.2 V 217
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)