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
2021-04-02 19:12:40 C 08 10 59.38 +11 56 03.4 V K74
2021-04-02 19:30:44 C 08 10 58.14 +11 56 30.5 q L47
2021-04-02 19:55:30 C 08 10 56.73 +11 57 03.9 a 233
2021-04-02 20:01:35 C 08 10 56.40 +11 57 11.9 a 233
2021-04-02 20:07:40 C 08 10 56.02 +11 57 19.4 a 233
2021-04-02 20:13:44 C 08 10 55.67 +11 57 27.3 a 233
2021-04-02 22:46:33 C 08 10 47.66 +12 00 35.5 V Z80
2021-04-02 22:51:33 C 08 10 47.39 +12 00 41.8 V Z80
2021-04-02 22:56:33 C 08 10 47.11 +12 00 48.7 V Z80
2021-04-03 03:21:30 C 08 10 35.08 +12 06 41.6 q W29
2021-04-03 03:46:48 C 08 10 33.67 +12 07 13.3 q W29
2021-04-03 03:52:25 C 08 10 34.65 +12 07 31.2 V 703
2021-04-03 04:00:00 C 08 10 34.19 +12 07 40.7 V 703
2021-04-03 04:00:29 C 08 10 34.14 +12 07 41.3 o 691
2021-04-03 04:07:35 C 08 10 33.73 +12 07 49.9 V 703
2021-04-03 04:11:54 C 08 10 32.26 +12 07 44.5 q W29
2021-04-03 04:15:10 C 08 10 33.39 +12 08 00.1 V 703
2021-04-03 04:42:43 C 08 10 31.60 +12 08 34.6 o 691
2021-04-03 05:22:08 C 08 10 29.28 +12 09 24.1 o 691
2021-04-03 05:24:57 C 08 10 29.12 +12 09 27.6 o 691
2021-04-03 06:07:10 C 08 10 26.70 +12 10 20.3 o 691
2021-04-03 06:46:35 C 08 10 24.52 +12 11 09.1 o 691
2021-04-03 06:49:24 C 08 10 24.39 +12 11 12.3 o 691
2021-04-03 06:58:10 C 08 10 25.98 +12 11 41.0 V T05
2021-04-03 07:23:11 C 08 10 22.63 +12 11 54.5 o 691
2021-04-03 07:42:22 C 08 10 23.26 +12 12 36.5 V T05
2021-04-03 07:54:09 C 08 10 21.08 +12 12 32.6 o 691
2021-04-03 07:54:17 C 08 10 22.55 +12 12 51.4 V T05
2021-04-03 18:31:58 C 08 09 55.84 +12 25 49.9 o 069
2021-04-03 18:41:49 C 08 09 55.30 +12 26 02.4 o 069
2021-04-03 18:51:48 C 08 09 54.76 +12 26 15.0 o 069
2021-04-04 05:25:56 S 08 09 25.712 +12 39 51.56 X 275
2021-04-04 18:43:48 C 08 08 54.68 +12 56 04.7 o 069
2021-04-04 18:48:19 C 08 08 54.96 +12 56 20.5 q L47
2021-04-04 18:53:47 C 08 08 54.17 +12 56 16.7 o 069
2021-04-04 19:03:48 C 08 08 53.66 +12 56 29.0 o 069
2021-04-04 19:21:52 C 08 08 53.06 +12 57 03.9 q L47
2021-04-04 19:41:21 C 08 08 52.59 +12 57 26.9 17.4 q 242
2021-04-04 19:46:33 C 08 08 52.31 +12 57 33.2 17.3 q 242
2021-04-04 20:25:49 C 08 08 50.24 +12 58 21.0 17.1 q 242
2021-04-04 20:50:37 C 08 08 48.95 +12 58 51.1 17.1 q 242
2021-04-04 21:11:03 C 08 08 48.17 +12 59 09.4 V Z80
2021-04-04 21:16:03 C 08 08 47.92 +12 59 15.2 V Z80
2021-04-05 02:55:06 C 08 08 34.02 +13 06 21.9 q W29
2021-04-05 02:59:20 C 08 08 33.79 +13 06 26.7 q W29
2021-04-05 03:03:23 C 08 08 33.56 +13 06 31.8 q W29
2021-04-05 03:48:39 C 08 08 33.36 +13 07 20.4 X U55
2021-04-05 04:02:09 C 08 08 32.67 +13 07 37.0 X U55
2021-04-05 04:15:34 C 08 08 31.99 +13 07 53.1 X U55
2021-04-05 07:47:46 C 08 08 22.16 +13 12 39.7 V T08
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)