Solar System
Dynamics
Group 		(99942) Apophis
2004 MN4
Older results

Apophis was discovered on June 19, 2004, by Roy A. Tucker, David J. Tholen, and Fabrizio Bernardi of the NASA-founded University of Hawaii Asteroid Survey from Kitt Peak National Observatory in Arizona.
Precovery observations from March 15, 2004 were identified on December 27, 2004.
Observations from the arc: June—December 2004 indicated a probability that Apophis would strike the Earth in 2029. The present observations eliminated that probability, however during the 2029 close encounter with Earth, Apophis would pass through a 'gravitational keyhole' — a well-defined region in space no more than about few hundred meters across — that would put it on a collision course with Earth in 2036 or later.


Older results

Number of original observations: 1483
Arc : 2004 03 15 - 2011 03 14
Nominal rms: 0″.21 (2950 residuals)

Possible collisions in: 2036, 2037, 2044, 2054, 2056, 2059, 2076



Distributions of the minimum distance of the asteroid Apophis from the centre of Earth in 2029 04 13 derived for the samples of 15000 virtual orbits.
The minimum-distance histograms for shorter arc ( Model E in Królikowska, Sitarski & Sołtan, 2009, MNRAS) is shown with a blue solid line, for the model based on longer arc is shown with a red solid line and filled histogram (see below),
while the model_2011 based on 1483 observations (2004 03 15 - 2011 03 14) is shown by a magenta filled histogram. According to presented results it seems that the additional observations taken in 2011 reduce the asteroid's impact probabilities (in: 2036, 2037, 2044, 2054, 2056, 2059, 2076) effectively to nil (see figure and impact orbits given below)

Thin dotted vertical lines representing the position of nominal orbits derived for Model E , for red model , and for the model_2011 are shown with a blue, red and magenta ink, respectively.

Distances for selected impacts at dates indicated by labels are presented by black vertical lines.

Impact orbit in 2076 is connected with very close encounter with Earth in 2051. Thus, the keyhole in 2029 is extremely narrow for the impact in 2076.
March 25, 2011; credits: Sitarski & Królikowska , Space Research Centre PAS

red model see Królikowska M. and Sitarski G. arXiv e-print: Note about the impact possibilities of asteroid (99942) Apophis



Year: 2036


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20360407 		0.922263089
21.03
1.108425237 		0.191058774
-24.27
0.191387306 		3.3313308
-8.88
2.1715008 		204.4601761
2.10
203.4808017 		126.3953244
-0.81
70.3080945 		84.7865855
-11.37
303.9200861 		0″.23

 

Impact date: 2036 04 13.366 (UT)   Vimpact= 12.918 km/sec   Ψimpact = 31°.47  

dev/σ
Deviation from the nominal orbit parameter divided by the respective uncertainty.
Vimpact
The velocity of the asteroid relative to the Earth at the moment of impact.
Ψimpact
The impact angle is measured from the vertical axis that goes through the impact point. Thus, the impact angle is 0 degrees for a vertical impact.
rms
Root mean square for the derived impact orbit.





Year: 2037


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20370407 		0.922263253
-21.22
1.093191572 		0.191058149
15.41
0.186805429 		3.3313201
5.01
2.3287045 		204.4601104
6.57
203.4812915 		126.3954303
-8.52
73.9614710 		84.7864382
16.47
300.0433996 		0″.23

 

Impact date: 2042 04 13.710(UT)   Vimpact= 13.058 km/sec   Ψimpact = 50°.40  



Year: 2044


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20440407 		0.922263252
-20.96
1.108351762 		0.191058123
17.06
0.190963984 		3.3313214
3.32
2.2960012 		204.4599680
16.26
203.2834858 		126.3955614
-18.07
70.2658222 		84.7864491
14.41
304.0441543 		0″.24

 

Impact date: 2044 04 13.260(UT)   Vimpact= 12.889 km/sec   Ψimpact = 56°.06  



Year: 2054


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20540407 		0.922263255
-21.73
1.086722380 		0.191058197
12.36
0.185182832 		3.3313212
3.58
2.3527616 		204.4601565
3.43
203.0276137 		126.3953852
-5.24
75.3931818 		84.7864267
18.64
298.6950458 		0″.24

 

Impact date: 2054 04 13.397(UT)   Vimpact= 12.537 km/sec   Ψimpact = 36°.65  



Year: 2056


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20560407 		0.922263256
-21.99
1.076907096 		0.191058018
23.72
0.183008320 		3.3313220
2.55
2.3518173 		204.4601672
2.70
203.1438129 		126.3953506
-2.72
78.1847058 		84.7864733
9.84
296.2748618 		0″.23

 

Impact date: 2056 04 13.188(UT)   Vimpact= 12.906 km/sec   Ψimpact = 38°.41  



Year: 2059


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20590407 		0.922263252
-20.96
1.102586437 		0.191058179
13.50
0.189249766 		3.3313198
5.40
2.3137198 		204.4601807
1.79
203.0819268 		126.3953682
-4.00
71.6561666 		84.7864285
18.30
302.1232186 		0″.23

 

Impact date: 2059 04 13.950 (UT)   Vimpact= 12.814 km/sec   Ψimpact = 75°.58  



Year: 2076


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20760407 		0.922263146
6.34
1.086675424 		0.191058604
-13.47
0.185403406 		3.3313282
-5.51
2.2686612 		204.4601380
-1.14
202.6213668 		126.3953735
4.69
75.4858831 		84.7865288
-0.65
299.3072400 		0″.23

 

Impact date: 2076 04 12.693(UT) (UT)   Vimpact= 12.638 km/sec   Ψimpact = 18°.25  



Older results
Number of original observations: 1399
Arc : 2004 03 15 - 2008 01 09
Nominal rms: 0″.27 (2774 residuals)

Possible collisions in: 2036, 2037, 2042, 2046, 2053, 2054, 2055, 2059, 2076
Largest impact probability found for 2036 (4.5·10-6)

Distributions of the minimum distance of the asteroid Apophis from the centre of Earth in 2029 04 13 derived for the samples of 15000 virtual orbits.
The minimum-distance histograms for shorter arc ( Model E in Królikowska, Sitarski & Sołtan, 2009, MNRAS ) is shown with a blue solid line,
while for the current model based on longer arc is shown with a red solid line and filled histogram.

Thin dotted vertical lines representing the position of nominal orbits derived for Model E and for current model are shown with a blue and red ink, respectively.

Distances for selected impacts at dates indicated by labels are presented by black vertical lines.

Impact orbit in 2076 is connected with very close encounter with Earth in 2051. Thus, the keyhole in 2029 is extremely narrow for the impact in 2076 and the probability of this impact is lower than the probability of impact in 2036.
credits: Królikowska & Sitarski, Space Research Centre PAS

see also Królikowska M. and Sitarski G. arXiv e-print: Note about the impact possibilities of asteroid (99942) Apophis



Year: 2036


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20360407 		0.922263089
3.75
1.108425255 		0.191058774
-5.30
0.191387310 		3.3313308
-5.39
2.1715008 		204.4601761
-1.21
203.4808017 		126.3953244
1.42
70.3080903 		84.7865855
-1.77
303.9200730 		0″.27

 

Impact date: 2036 04 13.366 (UT)   Vimpact= 12.918 km/sec   Ψimpact = 31°.47  

dev/σ
Deviation from the nominal orbit parameter divided by the respective uncertainty.
Vimpact
The velocity of the asteroid relative to the Earth at the moment of impact.
Ψimpact
The impact angle is measured from the vertical axis that goes through the impact point. Thus, the impact angle is 0 degrees for a vertical impact.
rms
Root mean square for the derived impact orbit.





Year: 2037


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20370407 		0.922263253
-9.60
1.093191630 		0.191058149
8.20
0.186805437 		3.3313201
6.62
2.3287042 		204.4601104
1.87
203.4812916 		126.3954303
-3.66
73.9614552 		84.7864382
10.33
300.0433493 		0″.27

 

Impact date: 2037 04 13.639(UT)   Vimpact= 12.929 km/sec   Ψimpact = 38°.82  



Year: 2042


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20420407 		0.922263090
3.67
1.129360634 		0.191058701
-3.73
0.197632721 		3.3313279
-2.13
2.1290961 		204.4601629
-0.59
203.2513785 		126.3953285
1.22
65.5642258 		84.7866090
-3.69
308.2909396 		0″.27

 

Impact date: 2042 04 13.710(UT)   Vimpact= 13.058 km/sec   Ψimpact = 50°.40  



Year: 2046


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20460407 		0.922263318
-14.89
1.086469829 		0.191057984
11.76
0.184803228 		3.3313197
7.07
2.4136332 		204.4601510
-0.03
202.9700793 		126.3954070
-2.54
75.4351911 		84.7863623
16.56
298.7125071 		0″.28

 

Impact date: 2046 04 13.335(UT)   Vimpact= 12.743 km/sec   Ψimpact = 4°.18  



Year: 2053


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20530406 		0.922263091
3.58
1.086422277 		0.191058671
-3.08
0.185414598 		3.3313283
-2.58
2.2203612 		204.4601331
0.80
202.8101339 		126.3953608
-0.33
75.5055171 		84.7866062
-3.46
298.1589961 		0″.27

 

Impact date: 2042 04 13.710(UT)   Vimpact= 13.058 km/sec   Ψimpact = 50°.40  



Year: 2054


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20540407 		0.922263255
-9.77
1.086722380 		0.191058197
7.16
0.185182832 		3.3313212
5.39
2.3527616 		204.4601565
-0.29
203.0276136 		126.3953852
-1.50
75.3931817 		84.7864267
11.27
298.6950453 		0″.28

 

Impact date: 2054 04 13.397(UT)   Vimpact= 12.537 km/sec   Ψimpact = 36°.65  



Year: 2055


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20550407 		0.922263322
-15.22
1.082023838 		0.191057966
12.15
0.183918511 		3.3313189
7.97
2.4075410 		204.4602070
-2.66
203.0562403 		126.3953508
0.15
76.6258306 		84.7863627
16.52
297.2038398 		0″.28

 

Impact date: 2055 04 13.726(UT)   Vimpact= 12.720 km/sec   Ψimpact = 9°.22  



Year: 2059


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20590407 		0.922263252
-9.52
1.102586437 		0.191058179
7.55
0.189249766 		3.3313198
6.96
2.3137198 		204.4601807
-1.43
203.0819268 		126.3953682
-0.68
71.6561666 		84.7864285
11.12
302.1232186 		0″.28

 

Impact date: 2059 04 13.950 (UT)   Vimpact= 12.814 km/sec   Ψimpact = 74°.58  



Year: 2076


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20760407 		0.922263146
1.10
1.086675504 		0.191058604
-0.97
0.185403404 		3.3313282
-1.02
2.2686633 		204.4601380
-1.14
202.6213339 		126.3953735
1.16
75.4858559 		84.7865288
-0.80
299.3071688 		0″.27

 

Impact date: 2076 04 12.693(UT) (UT)   Vimpact= 12.622 km/sec   Ψimpact = 18°.53  

Oldest results

Number of original observations: 1000
Arc : 2004 03 15 - 2006 08 16
Nominal rms: 0″.31 (1971 residuals)

Possible collisions in: 2036, 2037, 2046, 2048, 2054, 2055, 2059, 2065, 2076





Year: 2036


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20360407 		0.922263089
3.56
1.108425237 		0.191058774
-3.08
0.191387306 		3.3313308
-2.99
2.1715008 		204.4601761
-2.33
203.4808017 		126.3953244
2.69
70.3080945 		84.7865855
-3.12
303.9200861 		0″.31

 

Impact date: 2036 04 13.366 (UT)   Vimpact= 12.918 km/sec   Ψimpact = 31°.47  

Vimpact
The velocity of the asteroid relative to the Earth at the moment of impact.
Ψimpact
The impact angle is measured from the vertical axis that goes through the impact point. Thus, the impact angle is 0 degrees for a vertical impact.
rms
Root mean square for the derived impact orbit.





Year: 2037


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20370407 		0.922263251
-3.41
1.093191585 		0.191058226
3.73
0.186808827 		3.3313201
5.10
2.3277163 		204.4600465
1.72
203.4811471 		126.3954922
-2.51
73.9623655 		84.7864301
3.24
300.0430817 		0″.31

 

Impact date: 2037 04 13.639(UT)   Vimpact= 12.934 km/sec   Ψimpact = 38°.87  



Year: 2046


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20460407 		0.922263318
-6.30
1.086469829 		0.191057984
6.74
0.184803228 		3.3313197
5.40
2.4136332 		204.4601510
-1.55
202.9700793 		126.3954070
0.13
75.4351911 		84.7863623
6.01
298.7125071 		0″.31

 

Impact date: 2046 04 13.335(UT)   Vimpact= 12.743 km/sec   Ψimpact = 4°.18  



Year: 2048


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20480407 		0.922263443
-12.11
1.076877240 		0.191057625
10.27
0.182452222 		3.3313117
6.54
2.4934747 		204.4603120
7.89
203.3370970 		126.3952100
-9.43
78.0442963 		84.7863235
11.62
296.2100520 		0″.31
 

Impact date: 2048 04 13.281(UT)   Vimpact= 12.919 km/sec   Ψimpact = 22°.83  



Year: 2054


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20540407 		0.922263255
-3.59
1.086722381 		0.191058197
4.09
0.185182832 		3.3313212
4.27
2.3527616 		204.4601565
-1.72
203.0276135 		126.3953852
0.80
75.3931815 		84.7864267
3.38
298.6950449 		0″.31

 

Impact date: 2054 04 13.397(UT)   Vimpact= 12.537 km/sec   Ψimpact = 36°.65  



Year: 2055


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20550407 		0.922263322
-6.47
1.082023838 		0.191057966
6.96
0.183918511 		3.3313189
6.01
2.4075410 		204.4602070
-3.30
203.0562403 		126.3953508
1.87
76.6258306 		84.7863627
6.00
297.2038397 		0″.31

 

Impact date: 2055 04 13.726(UT)   Vimpact= 12.720 km/sec   Ψimpact = 9°.22  



Year: 2059


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20590407 		0.922263252
-3.46
1.102586437 		0.191058179
4.31
0.189249766 		3.3313198
5.33
2.3137198 		204.4601807
-2.48
203.0819268 		126.3953682
1.33
71.6561666 		84.7864285
3.30
302.1232186 		0″.31

 

Impact date: 2059 04 13.950 (UT)   Vimpact= 12.814 km/sec   Ψimpact = 74°.58  



Year: 2065


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20650407 		0.922263452
-12.06
1.086459350 		0.191057779
9.29
0.184570380 		3.3313206
4.72
2.5037114 		204.4600416
1.87
202.5976344 		126.3955222
-3.44
75.3981962 		84.7862200
11.84
299.1600541 		0″.31

 

Impact date: 2065 04 12.862(UT)   Vimpact= 12.730 km/sec   Ψimpact = 3°.98  



Year: 2076


Impact orbit for two dates (equ. J2000)

Epoch [TT] a [AU] e i [deg] Ω [deg] ω [deg] M [deg] rms
 
dev/σ
 		 20060922

20760407 		0.922263146
1.10
1.086675424 		0.191058604
-0.97
0.185403406 		3.3313282
-1.02
2.2686612 		204.4601380
-1.14
202.6213668 		126.3953735
1.16
75.4858831 		84.7865288
-0.80
299.3072400 		0″.31

 

Impact date: 2076 04 12.693(UT) (UT)   Vimpact= 12.650 km/sec   Ψimpact = 18°.13  

External links:

2004 MN4 page (NASA JPL) and Impact Risk page NEO Program (NASA JPL)
2004 MN4 page and Impact Risk page at the NEO Dynamic Site (NEODyS)





Solar System Dynamics & Planetology Group, 2008. All rights reserved