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
2021-03-11 18:51:30 C 09 02 55.04 -03 00 20.8 q 168
2021-03-11 21:32:57 C 09 02 28.37 -02 54 43.2 V 094
2021-03-11 21:46:01 C 09 02 26.14 -02 54 16.7 V 094
2021-03-11 22:03:02 C 09 02 23.62 -02 53 44.0 q L22
2021-03-11 22:08:18 C 09 02 22.72 -02 53 33.3 q L22
2021-03-11 22:27:33 C 09 02 19.06 -02 52 52.4 V 094
2021-03-11 22:33:13 C 09 02 20.12 -02 52 48.2 V Z80
2021-03-11 22:41:16 C 09 02 18.66 -02 52 19.2 V I79
2021-03-11 22:46:32 C 09 02 17.81 -02 52 20.9 V Z80
2021-03-11 22:59:52 C 09 02 15.55 -02 51 53.9 V Z80
2021-03-11 23:04:05 C 09 02 15.60 -02 51 22.4 o Z22
2021-03-11 23:14:12 C 09 02 13.11 -02 51 25.1 V Z80
2021-03-11 23:15:59 C 09 02 12.66 -02 51 09.7 V I79
2021-03-11 23:24:06 C 09 02 12.06 -02 50 42.4 o Z22
2021-03-11 23:35:57 C 09 02 07.63 -02 50 32.9 V 094
2021-03-11 23:44:04 C 09 02 08.49 -02 50 00.9 o Z22
2021-03-12 17:28:30 C 08 59 24.24 -02 14 37.3 q 168
2021-03-12 17:40:30 C 08 59 22.26 -02 14 13.1 q 168
2021-03-12 17:56:30 C 08 59 19.61 -02 13 40.7 q 168
2021-03-12 18:01:54 C 08 59 20.72 -02 13 19.5 V 073
2021-03-12 18:10:30 C 08 59 17.28 -02 13 12.7 q 168
2021-03-12 18:14:30 C 08 59 16.61 -02 13 04.3 q 168
2021-03-12 18:53:01 C 08 59 12.12 -02 11 37.0 V 073
2021-03-12 19:49:45 C 08 59 02.55 -02 09 42.7 V 073
2021-03-12 19:59:04 C 08 59 01.66 -02 09 29.5 V G34
2021-03-12 20:01:44 C 08 59 01.20 -02 09 23.7 V G34
2021-03-12 20:04:40 C 08 59 00.71 -02 09 18.3 V G34
2021-03-12 20:09:27 C 08 58 59.97 -02 09 08.0 V G34
2021-03-12 20:30:32 C 08 58 56.96 -02 08 19.9 V K19
2021-03-12 20:37:41 C 08 58 55.75 -02 08 05.5 V K19
2021-03-12 20:45:06 C 08 58 54.49 -02 07 50.5 V K19
2021-03-12 21:13:58 C 08 58 48.38 -02 06 53.6 V 073
2021-03-12 21:26:52 C 08 58 46.62 -02 06 30.4 q 056
2021-03-12 21:31:33 C 08 58 45.85 -02 06 20.4 q 056
2021-03-12 21:36:13 C 08 58 45.10 -02 06 12.8 q 056
2021-03-12 21:40:54 C 08 58 44.29 -02 06 01.9 q 056
2021-03-12 22:09:02 C 08 58 39.18 -02 05 02.0 V 073
2021-03-12 22:13:13 C 08 58 38.51 -02 04 53.7 V 073
2021-03-12 22:19:30 C 08 58 37.47 -02 04 41.0 V 073
2021-03-13 03:29:59 C 08 57 50.39 -01 52 39.8 q 834
2021-03-13 04:07:45 C 08 57 44.10 -01 51 23.3 q 834
2021-03-13 10:52:40 C 08 56 48.18 -01 39 15.7 t P66
2021-03-13 10:53:11 C 08 56 48.18 -01 39 15.7 t P66
2021-03-13 11:21:14 C 08 56 43.46 -01 38 18.5 t P66
2021-03-13 11:21:45 C 08 56 43.46 -01 38 18.5 t P66
2021-03-13 11:49:09 C 08 56 38.79 -01 37 22.5 t P66
2021-03-13 11:49:38 C 08 56 38.79 -01 37 22.5 t P66
2021-03-13 12:14:45 C 08 56 34.52 -01 36 31.1 t P66
2021-03-13 12:15:15 C 08 56 34.52 -01 36 31.1 t P66
2021-03-13 12:41:10 C 08 56 30.12 -01 35 38.4 t P66
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)