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
2021-03-07 02:56:03 C 09 21 58.11 -06 46 30.7 q 726
2021-03-07 03:01:05 C 09 21 57.10 -06 46 20.6 q 726
2021-03-07 03:01:14 C 09 21 56.67 -06 46 12.0 V W33
2021-03-07 03:01:55 C 09 21 58.83 -06 46 07.1 q U76
2021-03-07 03:08:28 C 09 21 55.24 -06 45 57.7 V W33
2021-03-07 03:10:34 C 09 21 57.16 -06 45 50.1 q U76
2021-03-07 03:15:43 C 09 21 53.80 -06 45 43.2 V W33
2021-03-07 03:18:55 C 09 21 55.53 -06 45 33.6 q U76
2021-03-07 03:22:56 C 09 21 52.37 -06 45 28.9 V W33
2021-03-07 03:30:12 C 09 21 50.92 -06 45 14.4 V W33
2021-03-07 03:37:27 C 09 21 49.48 -06 45 00.0 V W33
2021-03-07 03:44:41 C 09 21 48.05 -06 44 45.3 V W33
2021-03-07 04:54:34 C 09 21 36.88 -06 42 24.7 V U72
2021-03-07 05:46:43 C 09 21 26.54 -06 40 40.9 V U72
2021-03-07 05:55:57 S 09 21 22.727 -06 40 18.50 X 275
2021-03-07 06:38:46 C 09 21 16.22 -06 38 57.0 V U72
2021-03-07 09:13:41 C 09 20 48.23 -06 33 30.6 V T08
2021-03-07 09:19:00 C 09 20 47.15 -06 33 20.0 V T08
2021-03-07 09:19:27 C 09 20 43.79 -06 33 21.3 15.7 Y V26
2021-03-07 09:33:38 C 09 20 44.22 -06 32 50.6 V T08
2021-03-07 09:34:51 C 09 20 40.84 -06 32 49.7 15.0 Y V26
2021-03-07 10:19:25 C 09 20 32.58 -06 31 19.2 15.4 Y V26
2021-03-07 10:35:06 C 09 20 29.68 -06 30 47.3 Y V26
2021-03-07 12:17:57 C 09 20 16.60 -06 27 42.8 q D95
2021-03-07 12:22:08 C 09 20 15.78 -06 27 34.5 q D95
2021-03-07 12:26:21 C 09 20 14.95 -06 27 26.1 q D95
2021-03-07 12:28:26 C 09 20 14.54 -06 27 21.9 q D95
2021-03-07 16:02:40 C 09 19 38.93 -06 20 15.6 V C40
2021-03-07 16:41:17 C 09 19 31.66 -06 18 58.5 V C40
2021-03-07 16:42:48 C 09 19 31.38 -06 18 55.5 V C40
2021-03-07 16:47:27 C 09 19 30.49 -06 18 46.4 V C40
2021-03-07 16:48:58 C 09 19 30.21 -06 18 43.3 V C40
2021-03-07 16:50:32 C 09 19 29.91 -06 18 40.1 V C40
2021-03-07 17:09:02 C 09 19 26.39 -06 18 03.3 V C40
2021-03-07 17:20:23 C 09 19 24.13 -06 17 42.7 q L76
2021-03-07 17:22:55 C 09 19 23.64 -06 17 37.7 q L76
2021-03-07 17:25:26 C 09 19 23.17 -06 17 32.6 q L76
2021-03-07 17:31:31 C 09 19 22.09 -06 17 18.4 V C40
2021-03-07 17:34:35 C 09 19 21.50 -06 17 12.5 V C40
2021-03-07 17:37:40 C 09 19 20.91 -06 17 06.2 V C40
2021-03-07 17:40:45 C 09 19 20.32 -06 17 00.1 V C40
2021-03-07 17:48:28 C 09 19 18.84 -06 16 44.7 V C40
2021-03-07 17:51:33 C 09 19 18.25 -06 16 38.5 V C40
2021-03-07 18:04:20 C 09 19 15.79 -06 16 13.1 V C40
2021-03-07 18:05:25 C 09 19 14.76 -06 15 50.5 q M44
2021-03-07 18:06:30 C 09 19 14.05 -06 16 18.3 q 168
2021-03-07 18:09:45 C 09 19 13.88 -06 15 41.8 q M44
2021-03-07 18:12:40 C 09 19 14.50 -06 15 55.7 V 094
2021-03-07 18:13:40 C 09 19 14.33 -06 15 53.7 V 094
2021-03-07 18:15:34 C 09 19 12.74 -06 15 29.9 q M44
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)