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
2021-03-01 19:53:33 C 09 45 49.34 -10 48 47.7 V G34
2021-03-01 19:55:39 C 09 45 48.88 -10 48 43.9 V G34
2021-03-01 19:57:45 C 09 45 48.45 -10 48 40.3 V G34
2021-03-01 19:59:51 C 09 45 48.03 -10 48 37.0 V G34
2021-03-01 20:01:58 C 09 45 47.57 -10 48 32.9 V G34
2021-03-01 20:04:04 C 09 45 47.13 -10 48 29.5 V G34
2021-03-01 20:08:16 C 09 45 46.30 -10 48 22.3 V G34
2021-03-01 20:19:40 C 09 45 43.59 -10 47 58.6 V L54
2021-03-01 20:56:30 C 09 45 35.90 -10 46 53.1 V L54
2021-03-01 21:04:52 C 09 45 34.45 -10 46 39.9 V 118
2021-03-01 21:08:20 C 09 45 34.23 -10 46 30.8 a 233
2021-03-01 21:12:59 C 09 45 33.27 -10 46 22.8 a 233
2021-03-01 21:17:33 C 09 45 32.33 -10 46 14.1 a 233
2021-03-01 21:22:07 C 09 45 31.33 -10 46 06.2 a 233
2021-03-01 21:33:55 C 09 45 28.08 -10 45 46.4 V L54
2021-03-01 21:33:57 C 09 45 28.40 -10 45 48.0 V 118
2021-03-01 22:02:25 C 09 45 23.04 -10 44 58.2 V G33
2021-03-01 22:04:06 C 09 45 22.69 -10 44 55.6 V G33
2021-03-01 22:05:50 C 09 45 22.36 -10 44 52.5 V G33
2021-03-01 22:07:28 C 09 45 21.99 -10 44 49.7 V G33
2021-03-01 22:09:09 C 09 45 21.64 -10 44 46.5 V G33
2021-03-01 22:10:45 C 09 45 21.30 -10 44 44.0 V G33
2021-03-01 22:27:11 C 09 45 17.54 -10 44 11.0 q 595
2021-03-01 22:32:02 C 09 45 16.52 -10 44 02.4 q 595
2021-03-01 22:34:24 C 09 45 16.01 -10 43 58.0 q 595
2021-03-01 22:36:52 C 09 45 15.49 -10 43 53.6 q 595
2021-03-01 22:58:55 C 09 45 10.71 -10 43 15.3 V 118
2021-03-02 01:34:05 S 09 47 57.444 -10 52 04.08 V C57
2021-03-02 01:34:05 s 1 -109115.36 1 +353974.82 4060.0 C57
2021-03-02 01:44:05 S 09 47 55.145 -10 51 47.38 V C57
2021-03-02 01:44:05 s 1 -109436.80 7 +353750.08 9070.0 C57
2021-03-02 01:48:04 C 09 44 39.37 -10 36 52.4 q Y00
2021-03-02 01:49:28 C 09 44 39.08 -10 36 49.8 q Y00
2021-03-02 01:51:00 C 09 44 38.76 -10 36 46.6 q Y00
2021-03-02 01:54:05 S 09 47 52.865 -10 51 30.35 V C57
2021-03-02 01:54:05 s 1 -109757.94 3 +353524.33 3570.0 C57
2021-03-02 02:04:05 S 09 47 50.611 -10 51 12.64 V C57
2021-03-02 02:04:05 s 1 -110078.76 7 +353297.58 7570.0 C57
2021-03-02 02:14:05 S 09 47 48.377 -10 50 54.60 V C57
2021-03-02 02:14:05 s 1 -110399.27 8 +353069.84 1050.0 C57
2021-03-02 02:24:05 S 09 47 46.114 -10 50 37.79 V C57
2021-03-02 02:24:05 s 1 -110719.47 5 +352841.09 4020.0 C57
2021-03-02 02:34:05 S 09 47 43.798 -10 50 21.05 V C57
2021-03-02 02:34:05 s 1 -111039.35 6 +352611.34 6480.0 C57
2021-03-02 02:44:05 S 09 47 41.537 -10 50 04.45 V C57
2021-03-02 02:44:05 s 1 -111358.92 0 +352380.59 8420.0 C57
2021-03-02 02:54:05 S 09 47 39.257 -10 49 47.06 V C57
2021-03-02 02:54:05 s 1 -111678.16 7 +352148.83 9840.0 C57
2021-03-02 03:04:05 S 09 47 37.051 -10 49 29.03 V C57
2021-03-02 03:04:05 s 1 -111997.09 5 +351916.08 740.0 C57
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)