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
2021-02-21 21:50:03 C 10 22 18.85 -15 38 39.7 L28
2021-02-21 21:51:07 C 10 22 18.65 -15 38 38.7 L28
2021-02-21 21:52:11 C 10 22 18.45 -15 38 37.6 L28
2021-02-21 21:53:15 C 10 22 18.22 -15 38 36.4 L28
2021-02-21 21:54:19 C 10 22 18.01 -15 38 34.5 L28
2021-02-21 21:55:22 C 10 22 17.76 -15 38 33.4 L28
2021-02-21 21:55:42 C 10 22 17.37 -15 38 38.6 q 056
2021-02-21 21:56:26 C 10 22 17.58 -15 38 32.2 L28
2021-02-21 21:57:30 C 10 22 17.38 -15 38 31.1 L28
2021-02-21 22:00:27 C 10 22 16.44 -15 38 32.9 q 056
2021-02-21 22:00:41 C 10 22 17.00 -15 38 28.4 V K83
2021-02-21 22:04:54 C 10 22 16.16 -15 38 23.4 V K83
2021-02-21 22:05:12 C 10 22 15.45 -15 38 26.9 q 056
2021-02-21 22:09:57 C 10 22 14.53 -15 38 21.0 q 056
2021-02-21 22:13:17 C 10 22 14.47 -15 38 13.0 V K83
2021-02-21 22:14:41 C 10 22 13.58 -15 38 15.5 q 056
2021-02-21 22:19:26 C 10 22 12.63 -15 38 09.6 q 056
2021-02-21 22:24:10 C 10 22 11.67 -15 38 03.8 q 056
2021-02-21 22:24:50 C 10 22 12.16 -15 37 59.4 V K83
2021-02-21 22:28:56 C 10 22 10.72 -15 37 58.1 q 056
2021-02-21 22:33:41 C 10 22 09.77 -15 37 52.2 q 056
2021-02-21 22:38:26 C 10 22 08.82 -15 37 46.3 q 056
2021-02-22 00:27:50 C 10 21 47.67 -15 35 32.1 V G33
2021-02-22 00:34:34 C 10 21 46.33 -15 35 25.2 V G33
2021-02-22 04:09:51 C 10 21 07.24 -15 30 52.9 V 851
2021-02-22 04:20:58 C 10 21 04.96 -15 30 38.8 V 851
2021-02-22 06:20:55 C 10 20 44.38 -15 28 00.3 q U71
2021-02-22 06:37:22 C 10 20 41.04 -15 27 40.7 q U71
2021-02-22 06:54:20 C 10 20 37.57 -15 27 18.9 q U71
2021-02-22 10:02:07 C 10 20 01.83 -15 23 08.4 V T08
2021-02-22 10:04:46 C 10 20 01.28 -15 23 05.2 V T08
2021-02-22 10:08:45 C 10 20 00.45 -15 23 00.2 V T08
2021-02-22 10:18:44 C 10 19 58.38 -15 22 47.6 V T08
2021-02-22 18:11:19 C 10 18 32.04 -15 12 42.9 V M44
2021-02-22 18:26:26 C 10 18 29.05 -15 12 25.6 V M44
2021-02-22 18:41:31 C 10 18 25.90 -15 12 06.1 V M44
2021-02-22 20:44:37 C 10 18 00.32 -15 09 29.3 q M47
2021-02-22 20:47:17 C 10 17 59.68 -15 09 24.0 q M47
2021-02-22 20:53:32 C 10 17 58.42 -15 09 16.7 q M47
2021-02-22 20:56:16 C 10 17 57.75 -15 09 12.6 q M47
2021-02-22 20:59:43 C 10 17 57.18 -15 09 07.9 q M47
2021-02-22 21:19:19 C 10 17 55.26 -15 08 58.1 V L54
2021-02-22 21:43:42 C 10 17 50.41 -15 08 28.9 q 056
2021-02-22 21:48:27 C 10 17 49.44 -15 08 22.8 q 056
2021-02-22 21:53:11 C 10 17 48.48 -15 08 16.7 q 056
2021-02-22 21:57:56 C 10 17 47.53 -15 08 10.6 q 056
2021-02-22 22:02:40 C 10 17 46.57 -15 08 04.3 q 056
2021-02-22 22:21:04 C 10 17 42.70 -15 07 38.5 V L54
2021-02-22 23:28:06 C 10 17 29.02 -15 06 10.2 V L54
2021-02-23 00:29:47 C 10 17 17.90 -15 04 52.7 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)