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
2021-04-05 07:50:26 C 08 08 22.03 +13 12 42.9 V T08
2021-04-05 07:52:27 C 08 08 21.92 +13 12 45.2 V T08
2021-04-05 08:13:46 C 08 08 20.81 +13 13 10.6 V T08
2021-04-05 08:14:26 C 08 08 20.76 +13 13 11.2 V T08
2021-04-05 08:20:20 C 08 08 20.47 +13 13 18.2 V T08
2021-04-05 08:23:00 C 08 08 20.31 +13 13 21.3 V T08
2021-04-05 08:33:26 C 08 08 19.79 +13 13 33.5 V T08
2021-04-05 22:11:38 C 08 07 49.90 +13 29 32.7 V Z80
2021-04-05 22:16:38 C 08 07 49.61 +13 29 39.3 V Z80
2021-04-06 01:05:39 C 08 07 44.57 +13 33 54.4 H78
2021-04-06 01:07:50 C 08 07 44.45 +13 33 57.0 H78
2021-04-06 01:11:06 C 08 07 44.23 +13 34 00.1 H78
2021-04-06 01:12:12 C 08 07 44.18 +13 34 01.6 H78
2021-04-06 01:13:16 C 08 07 44.10 +13 34 02.8 H78
2021-04-06 01:21:41 C 08 07 43.66 +13 34 13.3 H78
2021-04-06 04:21:50 C 08 07 36.56 +13 37 14.7 V 703
2021-04-06 04:30:00 C 08 07 36.17 +13 37 24.1 V 703
2021-04-06 04:38:10 C 08 07 35.75 +13 37 33.7 V 703
2021-04-06 04:46:20 C 08 07 35.35 +13 37 43.3 V 703
2021-04-06 16:47:29 C 08 07 10.88 +13 51 37.7 q 168
2021-04-06 17:50:30 C 08 07 08.18 +13 52 50.5 q 168
2021-04-06 17:56:30 C 08 07 07.91 +13 52 57.3 q 168
2021-04-06 18:58:00 C 08 07 05.42 +13 54 08.2 q 168
2021-04-06 20:12:33 C 08 07 03.27 +13 55 37.9 o 069
2021-04-06 20:24:32 C 08 07 02.73 +13 55 52.4 o 069
2021-04-06 20:32:20 C 08 07 02.45 +13 56 00.7 o 069
2021-04-06 22:46:53 C 08 06 57.41 +13 58 41.2 V Z80
2021-04-06 22:51:53 C 08 06 57.21 +13 58 47.5 V Z80
2021-04-06 22:56:53 C 08 06 57.00 +13 58 52.8 V Z80
2021-04-07 04:06:53 C 08 06 47.31 +14 05 15.8 V G96
2021-04-07 04:13:43 C 08 06 46.98 +14 05 23.5 V G96
2021-04-07 04:20:32 C 08 06 46.67 +14 05 31.3 V G96
2021-04-07 04:27:23 C 08 06 46.35 +14 05 39.0 V G96
2021-04-07 13:44:06 C 08 06 27.08 +14 16 18.6 q 900
2021-04-07 13:54:12 C 08 06 26.67 +14 16 29.9 q 900
2021-04-07 19:12:19 C 08 06 18.40 +14 22 21.8 o 069
2021-04-07 19:16:20 C 08 06 18.57 +14 22 37.3 q L47
2021-04-07 19:24:19 C 08 06 17.92 +14 22 35.4 o 069
2021-04-07 19:36:13 C 08 06 17.66 +14 22 59.9 q L47
2021-04-07 19:36:20 C 08 06 17.40 +14 22 48.5 o 069
2021-04-07 20:18:29 C 08 06 15.86 +14 23 47.8 q 160
2021-04-07 20:21:24 C 08 06 15.75 +14 23 51.4 q 160
2021-04-07 20:24:17 C 08 06 15.61 +14 23 54.9 q 160
2021-04-08 19:23:27 C 08 05 34.59 +14 50 01.4 q L47
2021-04-08 19:40:49 C 08 05 33.97 +14 50 20.7 q L47
2021-04-09 00:03:35 C 08 05 27.56 +14 55 58.3 H78
2021-04-09 00:07:56 C 08 05 27.35 +14 56 03.6 H78
2021-04-09 00:22:22 C 08 05 26.15 +14 55 34.6 V I22
2021-04-09 00:23:02 C 08 05 26.12 +14 55 35.6 V I22
2021-04-09 00:23:41 C 08 05 26.10 +14 55 36.1 V I22
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)