List of asteroid close approaches to Earth

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Trajectory of 2004 FH in the Earth–Moon system.
Goldstone radar images of an asteroid 2007 PA8's Earth flyby in 2012.

This is a list of examples where an asteroid or meteoroid travels close to the Earth. Some are regarded as potentially hazardous objects if they are estimated to be large enough to cause regional devastation.

Near-Earth object detection technology greatly improved around 1998, so objects being detected as of 2004 could have been missed only a decade earlier due to a lack of dedicated Near-Earth sky surveys. As dedicated Near-Earth sky surveys improve, smaller and smaller asteroids are regularly being discovered. The small near-Earth asteroids 2008 TC3 and 2014 AA are the only two asteroids discovered before impacting into Earth. Scientists estimate that several dozen asteroids in the 6 to 12 meter size range fly by Earth at a distance closer than the moon every year, but only a fraction of these are actually detected.[1]

Timeline of close approaches within one lunar distance to Earth[edit]

The average distance to the Moon (or LD) is about 384,400 km.[2] Below are lists of close approaches less than one LD for a given year. (See also near-Earth asteroids published by the International Astronomical Union[note 1] and NEO Earth Close Approaches.):

Closest per year[edit]

From the lists above, these are the closest known asteroids per year that approach Earth within one lunar distance LD and without impacting. More than one asteroid per year may be listed if its geocentric distance[note 2] is less than 0.100 LD. The table shows the year 2016 has six such close encounters. (For comparison, since a satellite in a geostationary orbit has an altitude of about 36,000 km, then its geocentric distance is 0.110 LD.)

Satellites in geostationary orbit.
Year Date of
closest approach
Object Nominal
geocentric
distance[note 3]
(in thousand km)
Nominal
geocentric
distance
(in LD)
Size of object
(approx.)
(H)
2017 2017-10-12 2012 TC4 14.4 0.037 10–31 meters 26.7[3]
2017-03-02 2017 EA 20.9 0.054 1–5 meters 30.7[4]
2016 2016-02-25 2016 DY30 14.3 0.037 2–5 meters 30.5[5]
2016-09-11 2016 RN41 23.7 0.062 1–5 meters 31.0[6]
2016-01-12 2016 AH164 26.7 0.069 3–7 meters 29.6[7]
2016-03-11 2016 EF195[8] 31.7 0.082 16–31 meters 25.6[9]
2016-11-05 XV88D4F 36.7 0.095 2–7 meters 30.0[10]
2016-01-14 2016 AN164 37.0 0.096 2–5 meters 30.5[11]
2015 2015-09-22 2015 SK7 26.6 0.069 3–14 meters 28.9[12]
2015-11-15 2015 VY105 34.6 0.090 4–9 meters 29.0[13]
2014 2014-06-03 2014 LY21 16.7 0.044 4–8 meters 29.1[14]
2013 2013-12-23 2013 YB 27.3 0.071 3 meters 31.4[15]
2013-02-15 367943 Duende 34.1 0.089 30 meters 24.0[16]
2012 2012-05-29 2012 KT42 20.8 0.054 9 meters 29.0[17]
2011 2011-02-04 2011 CQ1[18] 11.9 0.031 1 meter 32.1[19]
2011-06-27 2011 MD 18.7 0.049 14 meters 28.0[20]
2010 2010-11-17 2010 WA 38.9 0.101 2–6 meters 30.0[21]
2009 2009-11-06 2009 VA 20.4 0.053 4–13 meters 28.6[22]
2008 2008-10-09 2008 TS26 12.6 0.033 0.5-1.6 meters 33.2[23]
2008-10-20 2008 US 32.9 0.086 1–4 meters 31.4[24]
2004 2004-03-31 2004 FU162 12.9 0.034 4–12 meters 28.7[25]

Notable cases are the relatively large asteroids 2016 EF195 and Duende, with the latter coincidentally approaching just a few hours after the unrelated Chelyabinsk meteor.

Largest per year[edit]

From the lists above, these are the largest known asteroids per year that approach Earth within one LD. (More than one asteroid per year may be listed if its size is 100 meters or more.) For comparison, the 2013 Chelyabinsk meteor which caused a large airburst over Russia was estimated to be just 20 meters across.

Animation of the trajectory of the asteroid 2005 YU55 compared with the orbits of Earth and the Moon on 8–9 November 2011.
Trajectory of the relatively large 2005 YU55 compared with the orbits of Earth and the Moon on 8–9 Nov 2011.
Year Date of
closest approach
Object Nominal
geocentric
distance
(in thousand km)
Nominal
geocentric
distance
(in LD)
Size of object
(approx.)
(H)
2017 2017-03-05 2017 DS109 353 0.92 12–49 meters 25.9[26]
2016 2016-03-21 2016 FN56 384 1.00 35–86 meters 24.2[27]
2015 2015-01-18 2015 BP513 240 0.62 12–27 meters 26.7[28]
2014 2014-03-05 2014 DX110 349 0.91 20–40 meters 25.7[29]
2013 2013-08-04 2013 PJ10 371 0.97 60 meters 24.6[30]
2012 2012-04-01 2012 EG5 230 0.60 60 meters 24.3[31]
2011 2011-11-08 (308635) 2005 YU55 324 0.84 360 meters 21.9[32]
2011-12-03 2011 XC2 347 0.90 100 meters 23.1[33]
2010 2010-11-02 2010 UJ7 286 0.74 20–49 meters 25.4[34]
2009 2009-03-02 2009 DD45 72 0.19 15–47 meters 25.8[35]
2008 2008-02-15 2008 CK70 371 0.97 22–71 meters 24.9[36]
2007 2007-01-18 2007 BD 324 0.84 18–57 meters 25.4[37]
2006 2006-02-23 2006 DD1 117 0.31 11–34 meters 26.5[38]
2005 2005-12-05 2005 XA8 217 0.57 15–49 meters 25.7[39]
2004 2004-03-18 2004 FH 49 0.13 15–49 meters 25.7[40]
2003 2003-12-06 2003 XJ7 148 0.39 11–36 meters 26.4[41]
2002 2002-06-14 2002 MN 120 0.31 40–130 meters 23.6[42]
2001 2001-01-15 2001 BA16 306 0.80 13–43 meters 26.0[43]
1999 1999-08-12 2016 CD137 179 0.47 13–43 meters 26.0[44]
1994 1994-12-09 1994 XM1 105 0.27 5–16 meters 28.2[45]
1993 1993-05-20 1993 KA2 149 0.39 3–11 meters 29.0[46]
1991 1991-04-08 2012 UE34 322 0.84 46–149 meters 23.3[47]
1990 1990-09-19 2003 SW130 186 0.48 3–10 meters 29.1[48]
1988 1988-10-16 2010 UK 322 0.84 9–30 meters 26.8[49]
1982 1982-11-04 2012 TY52 314 0.82 111-358 meters 21.4[50]
1980 1980-05-18 2009 WW7 74 0.19 4-11 meters 28.9[51]

The year 2011 was notable as two asteroids with size 100 meters or more approached within one lunar distance.

Passed by outside of atmosphere[edit]

Objects with distances greater than 100 km are listed here, although there is no discrete beginning of space. The lists do not pretend to completeness.

Objects < 50 meters[edit]

Asteroids smaller than about 50 meters.[52]

Nominal geocentric
distance (AU)
Nominal geocentric
distance (km)
Size (m)
(approximate)
Date of
closest approach
Object
0.000079 11,900 1 February 4, 2011 2011 CQ1[19]
0.000084 12,500 1 October 9, 2008 2008 TS26[23]
0.000086 12,900 6 March 31, 2004 2004 FU162
0.000125 18,700 10 June 27, 2011 2011 MD[20][53]
0.000137 20,400 7 November 6, 2009 2009 VA
0.000139 20,800 4–10 May 29, 2012 2012 KT42
0.000177 26,500 3-14 September 22, 2015 2015 SK7
0.00018 27,000 3 December 23, 2013 2013 YB[54]
0.000228 34,100 40×20[55] February 15, 2013 367943 Duende[56][57]
0.000260 38,900 3 November 17, 2010 2010 WA[58]
0.000328 49,100 30 March 18, 2004 2004 FH
0.000346 51,800 5–10 October 12, 2010 2010 TD54
0.000383 57,300 25 May 28, 2012 2012 KP24[59][60]
0.000437 65,400 8 January 27, 2012 2012 BX34
0.000482 72,100 9 September 8, 2010 2010 RK53[61]
0.000483 72,200 19 March 2, 2009 2009 DD45
0.000484 72,400 2–7 December 11, 2013 2013 XS21[62]
0.000531 79,400 7 September 8, 2010 2010 RF12[63]
0.000564 84,300 5 September 27, 2003 2003 SQ222[64]
0.000568 85,000 15 March 18, 2009 2009 FH[65]
0.000635 95,000 17 October 12, 2012 2012 TC4[66]
0.000704 105,400 10 December 9, 1994 1994 XM1[67][68]
0.000856 128,000 2 October 13, 2015 2015 TC25
0.000862 129,000 15–30 January 13, 2010 2010 AL30
0.000998 149,200 7 May 20, 1993 1993 KA2[67][69]
0.001124 168,200 6–10 January 18, 1991 1991 BA
0.001539 230,200 47 April 1, 2012 2012 EG5[70]
0.001655 247,600 12 September 8, 2010 2010 RX30[71]
0.002454 367,100 10–17 March 4, 2013 2013 EC[72]
0.00257 384,400 average distance to the Moon[2]
0.002899 433,600 22 April 9, 2010 2010 GA6

Objects > 50 meters[edit]

Goldstone radar image of asteroid 2005 YU55 taken November 7, 2011.

Asteroids larger than about 50 meters.[52][73]

Nominal geocentric
distance (AU)
Nominal geocentric
distance (km)
Size (m)
(approximate)
Date of
closest approach
Object
0.000802 120,000 73 June 14, 2002 2002 MN
0.00155* 233,000 500 December 31, 1914 (152680) 1998 KJ9
0.00159* 239,000 200 April 11, 1971 2002 JE9
0.00210* 314,000 200 November 4, 1982 2012 TY52
0.002172 324,900 360 November 8, 2011 (308635) 2005 YU55
0.00219* 328,000 150 October 17, 1976 2013 UG1
0.0022** 329,000 100 April 8, 1991 2012 UE34
0.0023* 340,000 730 August 30, 1925 (163132) 2002 CU11
0.0023 340,000 100 December 3, 2011 2011 XC2
0.00257 384,400 average distance to the Moon[2]
<0.00266* <398,000 100 January 6, 1936 2010 VB1
0.002891 432,400 500 July 3, 2006 2004 XP14
0.003704 554,200 250 January 29, 2008 2007 TU24
0.004241* 634,500 300 April 26, 1942 69230 Hermes
0.004572 684,000 300 March 22, 1989 4581 Asclepius
0.004950 740,500 300 October 30, 1937 69230 Hermes
0.0062* 930,000 200 December 27, 1976 2010 XC15
0.00836 1,251,000 325 June 8, 2014 2014 HQ124
0.0093* 1,390,000 5000 August 27, 1969 (192642) 1999 RD32
0.0124855 1,867,800 400 December 16, 2001 (33342) 1998 WT24
0.036415 5,447,600 1000 June 14, 2012 2012 LZ1
0.043294 6,476,600 1600 November 5, 2012 (214869) 2007 PA8[74][75]
0.046332 6,900,000 5400 December 12, 2012 4179 Toutatis[76][77]

Asteroids with large uncertainty regions are not included.

* Asteroid approach did NOT occur during an observed apparition. Passage is calculated by integrating the equations of motion.

** Only the nominal (best-fit) orbit shows a passage this close. The uncertainty region is still somewhat large due to a short observation arc.

Predicted encounters[edit]

Incomplete list of asteroids larger than about 50 meters predicted to pass close to Earth:[73][78]

Nominal geocentric
distance (AU)
Nominal geocentric
distance (km)
Size (m)
(approximate)
Date of
closest approach
Object
0.000256 38,300 325 April 13, 2029 99942 Apophis
0.000670 100,200 75–170 October 19, 2129 2007 UW1
0.000721 107,800 50–120 April 8, 2041 2012 UE34
0.001572 235,200 170–370 January 2, 2101 (456938) 2007 YV56[79]
0.001585 237,000 360±40 November 8, 2075 (308635) 2005 YU55
0.001629 243,700 370–840 December 1, 2140 (153201) 2000 WO107
0.001635** 244,600 190–420 October 26, 2087 2011 WL2
0.001663 248,800 700–1500 June 26, 2028 (153814) 2001 WN5
0.001980 296,200 170–370 January 22, 2148 (85640) 1998 OX4[80]
0.002222 332,500 190–250 May 28, 2065 2005 WY55
0.002241 335,200 75–170 March 23, 2146 2009 DO111
0.00257 384,400 average distance to the Moon[2]

A list of predicted NEO approaches at larger distances is maintained as a database by the NASA Near Earth Object Program.[81]

** Only the nominal (best-fit) orbit shows a passage this close. The uncertainty region is still somewhat large due to a short observation arc.

Earth grazers[edit]

All-sky photo with the Earth-grazing meteoroid of 13 October 1990 (the light track across the picture going from the south to the north) taken at Červená hora (Czechoslovakia), one of the stations of the European Fireball Network. The bright track on the left is the Moon.

Objects which enter and then leave Earth's atmosphere, the so-called 'Earth-grazers,' are a distinct phenomenon, in as much as entering the lower atmosphere can constitute an impact event rather than a close pass. Earth grazer can also be short for a body that "grazes" the orbit of the Earth, in a different context.

Altitude
(km)
Size (m)
(approximate)
Mass (kg)
(approximate)
Date of
closest approach
Object Note Ref.
0 mean sea level
8.8 Mount Everest (height)
58 5 105–106 August 10, 1972 1972 Great Daylight Fireball above the United States and Canada First scientifically observed [82]
71.4 100 March 29, 2006 2006 Earth-grazing Fireball above Japan

[83]

98.7 44 October 13, 1990 1990 Earth-grazing Fireball above Czechoslovakia and Poland First captured from 2 distant locations, which enabled computing its orbit by geometrical methods [84]
August 7, 2007 2007 Earth-grazing Fireball Its pre-encounter orbit belonged to the rare Aten type. [85]
100 Kármán line

Animation[edit]

Here is simulated animation of the course of 2015 TB145, a NEO during close approach to the Earth

Asteroid flyby 2015 TB145.gif
An animation of the flyby, as seen from the center of the Earth, with hourly trace circles along the path of motion

Overview[edit]

Plot of orbits of known Potentially Hazardous Asteroids (size over 460 feet (140 m) and passing within 4.7 million miles (7.6×10^6 km) of Earth's orbit) as of early 2013 (alternate image).

Notes[edit]

  1. ^ : "Near Earth Asteroids (NEAs): A Chronology of Milestones".
  2. ^ Distance from the center of Earth to the center of the object. See the NASA/JPL Solar System Dynamics Glossary: Geocentric. Earth has a radius of approximately 6,400 km.
  3. ^ Distance from the center of Earth to the center of the object. See the NASA/JPL Solar System Dynamics Glossary: Geocentric. Earth has a radius of approximately 6,400 km.

References[edit]

  1. ^ Responding to Potential Asteroid Redirect Mission Targets
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External links[edit]