List of asteroid close approaches to Earth

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

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

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 0.10 LD. The table shows the year 2016 has three 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 0.11 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)
2016 2016-02-25 2016 DY30 14 0.04 2–5 meters30.5[3]
2016 2016-01-12 2016 AH164 27 0.07 3–7 meters29.6[4]
2016 2016-03-11 2016 EF195[5] 32 0.08 16–31 meters25.6[6]
2015 2015-09-22 2015 SK7 27 0.07 3–14 meters28.9[7]
2015 2015-11-15 2015 VY105 35 0.09 4–9 meters29.0[8]
2014 2014-06-03 2014 LY21 15 0.04 4–8 meters 29.1[9]
2013 2013-12-23 2013 YB 27 0.07 3 meters 31.4[10]
2013 2013-02-15 367943 Duende 34 0.09 30 meters 24.0[11]
2012 2012-05-29 2012 KT42 21 0.05 9 meters 29.0[12]
2011 2011-02-04 2011 CQ1[13] 12 0.03 1 meters32.1[14]
2011 2011-06-27 2011 MD 19 0.05 14 meters 28.0[15]
2010 2010-11-17 2010 WA 39 0.10 2–6 meters 30.0[16]

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

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)
2016 2016-03-21 2016 FN56 384 1.00 35–86 meters 24.2[17]
2015 2015-01-18 2015 BP513 240 0.62 12–27 meters 26.7[18]
2014 2014-03-05 2014 DX110 349 0.91 20–40 meters 25.7[19]
2013 2013-08-04 2013 PJ10 3710.97 60 meters 24.6[20]
2012 2012-04-01 2012 EG5 2300.60 60 meters 24.3[21]
2011 2011-11-08 2005 YU55 324 0.84 360 meters 21.9[22]
2011 2011-12-03 2011 XC2 347 0.90 100 meters 23.1[23]
2010 2010-11-02 2010 UJ7 286 0.74 20–49 meters 25.4[24]

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

Passed by outside of atmosphere

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

Asteroids smaller than about 50 meters.[25]

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[14]
0.000084 12,500 1 October 9, 2008 2008 TS26[26]
0.000086 12,900 6 March 31, 2004 2004 FU162
0.000125 18,700 10 June 27, 2011 2011 MD[15][27]
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[28]
0.000228 34,100 40×20[29] February 15, 2013 367943 Duende[30][31]
0.000260 38,900 3 November 17, 2010 2010 WA[32]
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[33][34]
0.000437 65,400 8 January 27, 2012 2012 BX34
0.000482 72,100 9 September 8, 2010 2010 RK53[35]
0.000483 72,200 19 March 2, 2009 2009 DD45
0.000484 72,400 2–7 December 11, 2013 2013 XS21[36]
0.000531 79,400 7 September 8, 2010 2010 RF12[37]
0.000564 84,300 5 September 27, 2003 2003 SQ222[38]
0.000568 85,000 15 March 18, 2009 2009 FH[39]
0.000635 95,000 17 October 12, 2012 2012 TC4[40]
0.000704 105,400 10 December 9, 1994 1994 XM1[41][42]
0.000862 129,000 15–30 January 13, 2010 2010 AL30
0.000998 149,200 7 May 20, 1993 1993 KA2[41][43]
0.001124 168,200 6–10 January 18, 1991 1991 BA
0.001539 230,200 47 April 1, 2012 2012 EG5[44]
0.001655 247,600 12 September 8, 2010 2010 RX30[45]
0.002454 367,100 10–17 March 4, 2013 2013 EC[46]
0.00257 384,400 average distance to the Moon[2]
0.002899 433,600 22 April 9, 2010 2010 GA6

Objects > 50 meters

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

Asteroids larger than about 50 meters.[25][47]

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
0.0432946,476,600 1600 November 5, 2012 (214869) 2007 PA8[48][49]
0.0463326,900,000 5400 December 12, 2012 4179 Toutatis[50][51]

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

Incomplete list of asteroids larger than about 50 meters predicted to pass close to Earth:[47][52]

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 2007 YV56[53]
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[54]
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.[55]

** 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

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, inasmuch 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 [56]
71.4 100 March 29, 2006 2006 Earth-grazing Fireball above Japan

[57]

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 [58]
August 7, 2007 2007 Earth-grazing Fireball Its pre-encounter orbit belonged to the rare Aten type. [59]
100 Kármán line

Animation

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


An animation of the flyby, as seen from the center of the Earth, with hourly trace circles along the path of motion

Overview

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

  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

  1. ↑ Responding to Potential Asteroid Redirect Mission Targets
  2. 1 2 3 4 NASA Staff (10 May 2011). "Solar System Exploration: Planets: Earth's Moon: Facts & Figures". NASA. Retrieved 6 November 2011.
  3. ↑ "JPL Small-Body Database Browser: (2016 DY30)" (last observation: 2016-02-27).
  4. ↑ "JPL Small-Body Database Browser: (2016 AH164)" (last observation: 2016-01-13).
  5. ↑ "Small asteroid detected 4 days after passing as close as satellites".
  6. ↑ "JPL Small-Body Database Browser: (2016 EF195)" (last observation: 2016-03-17).
  7. ↑ "JPL Small-Body Database Browser: (2015 SK7)" (last observation: 2015-10-13).
  8. ↑ "JPL Small-Body Database Browser: (2015 VY105)" (last observation: 2015-11-15).
  9. ↑ "JPL Small-Body Database Browser: (2014 LY21)" (last observation: 2014-06-02).
  10. ↑ "JPL Small-Body Database Browser: (2013 YB)" (last observation: 2013-12-23).
  11. ↑ "JPL Small-Body Database Browser: 367943 Duende (2012 DA14)" (last observation: 2013-02-21).
  12. ↑ "JPL Small-Body Database Browser: (2012 KT42)" (2012-05-29 last obs).
  13. ↑ Yeomans, Don; Chodas, Paul (4 February 2011). "Very Small Asteroid Makes Close Earth Approach on February 4, 2011". Near-Earth Object Program Office. NASA/JPL. Retrieved 22 February 2013.
  14. 1 2 "JPL Small-Body Database Browser: (2011 CQ1)" (2011-02-04 last obs).
  15. 1 2 "JPL Small-Body Database Browser: (2011 MD)" (2011-07-03 last obs (arc=12 days)).
  16. ↑ "JPL Small-Body Database Browser: (2010 WA)" (last observation: 2010-11-17).
  17. ↑ "JPL Small-Body Database Browser: (2016 FN56)" (last observation: 2016-04-05).
  18. ↑ "JPL Small-Body Database Browser: (2015 BP513)" (last observation: 2015-01-29).
  19. ↑ "JPL Small-Body Database Browser: (2014 DX110)" (last observation: 2014-03-05).
  20. ↑ "JPL Small-Body Database Browser: (2013 PJ10)" (last observation: 2013-09-09).
  21. ↑ "JPL Small-Body Database Browser: (2012 EG5)" (2012-04-03 last obs).
  22. ↑ "JPL Small-Body Database Browser: (2005 YU55)" (2011-12-16 last obs).
  23. ↑ "JPL Small-Body Database Browser: (2011 XC2)" (2011-12-30 last obs (arc=22 days)).
  24. ↑ "JPL Small-Body Database Browser: (2010 UJ7)" (last observation: 2010-11-02).
  25. 1 2 "Closest Approaches to the Earth by Minor Planets". International Astronomical Union/Minor Planet Center. Retrieved 12 February 2013.
  26. ↑ "JPL Small-Body Database Browser: (2008 TS26)" (2008-10-09 last obs). Retrieved 12 February 2013.
  27. ↑ Benner, Lance A. M. "2011 MD Goldstone Radar Observations Planning". Asteroid Radar Research. JPL/California Institute of Technology. Retrieved 22 February 2013.
  28. ↑ "JPL Small-Body Database Browser: (2013 YB)" (2013-12-23 last obs). Retrieved 2013-12-24.
  29. ↑ Benner, Lance A. M. "2012 DA14 Goldstone Radar Observations Planning". Asteroid Radar Research. JPL/California Institute of Technology. Retrieved 20 February 2013.
  30. ↑ "NEOs Removed from Impact Risk Tables". Near-Earth Object Program Office. NASA/JPL. Retrieved 17 February 2013.
  31. ↑ "JPL Small-Body Database Browser: (2012 DA14)" (2013-02-16 last obs). Retrieved 17 February 2013.
  32. ↑ "JPL Small-Body Database Browser: (2010 WA)" (2010-11-17 last obs). Retrieved 12 February 2013.
  33. ↑ "JPL Small-Body Database Browser: (2012 KP24)" (2012-05-28 last obs). Retrieved 16 February 2013.
  34. ↑ Plait, Phil (25 May 2012). "Small asteroid to buzz Earth on May 28". Discover. Retrieved 16 February 2013.
  35. ↑ "JPL Small-Body Database Browser: (2010 RK53)" (2010-09-17 last obs). Retrieved 1 March 2013.
  36. ↑ "JPL Small-Body Database Browser: (2013 XS21)" (2013-12-14 last obs).
  37. ↑ "2010 RF12 Earth Impact Risk Summary". Near-Earth Object Program Office. NASA/JPL. Retrieved 12 February 2013.
  38. ↑ "JPL Small-Body Database Browser: (2003 SQ222)" (2003-10-02 last obs). Retrieved 12 February 2013.
  39. ↑ "JPL Small-Body Database Browser: (2009 FH)" (2009-03-18 last obs). Retrieved 1 March 2013.
  40. ↑ "JPL Small-Body Database Browser: (2012 TC4)" (2012-10-11 last obs). Retrieved 12 February 2013.
  41. 1 2 Williams, David R. "Near Earth Object Fact Sheet". Lunar & Planetary Science. NASA Goddard Space Flight Center. Retrieved 17 February 2013.
  42. ↑ "JPL Small-Body Database Browser: (1994 XM1)" (1994-12-09 last obs). Retrieved 17 February 2013.
  43. ↑ "JPL Small-Body Database Browser: (1993 KA2)" (1993-05-22 last obs). Retrieved 17 February 2013.
  44. ↑ "JPL Small-Body Database Browser: (2012 EG5)" (2012-04-03 last obs). Retrieved 1 March 2013.
  45. ↑ "JPL Small-Body Database Browser: (2010 RX30)" (2010-09-08 last obs).
  46. ↑ "JPL Small-Body Database Browser: (2013 EC)" (2013-03-03 last obs). Retrieved 4 June 2015.
  47. 1 2 "NEO Earth Close-Approaches (Between 1900 A.D. and 2200 A.D., NEOs with H <=22, nominal distance within 5 LD)". Near-Earth Object Program Office. NASA/JPL. Retrieved 17 May 2015.
  48. ↑ Benner, Lance A. M. "(214869) 2007 PA8 Goldstone Radar Observations Planning". Asteroid Radar Research. JPL/California Institute of Technology. Retrieved 14 February 2013.
  49. ↑ "JPL Small-Body Database Browser: 214869 (2007 PA8)" (2013-02-13 last obs). Retrieved 15 February 2013.
  50. ↑ "JPL Small-Body Database Browser: 4179 Toutatis (1989 AC)" (2012-12-08 last obs). Retrieved 12 February 2013.
  51. ↑ Atkinson, Nancy (11 December 2012). "Two Asteroids Will Buzz Past Earth on December 11". Universe Today. Retrieved 12 February 2013.
  52. ↑ "PHA Close Approaches To The Earth". International Astronomical Union/Minor Planet Center. Retrieved 14 November 2011.
  53. ↑ "JPL Small-Body Database Browser: (2007 YV56)" (2012-01-29 last obs). Retrieved 17 February 2013.
  54. ↑ "JPL Small-Body Database Browser: 85640 (1998 OX4)" (2008-07-29 last obs). Retrieved 17 February 2013.
  55. ↑ NASA, Near Earth Object Program, database NEO Earth Close-Approaches Between 1900 A.D. and 2200 A.D. limited to encounters with reasonably low uncertainty (accessed 20 Sept. 2013)
  56. ↑ Ceplecha, Z. (March 1994). "Earth-grazing daylight fireball of August 10, 1972" (PDF). Astronomy and Astrophysics 283 (1): 287–288. Bibcode:1994A&A...283..287C. ISSN 0004-6361. Retrieved 2015-03-14.
  57. ↑ S., Abe; J., Borovička; P., Spurný; P., Koten; Z., Ceplecha; Meteor Network Team in Japan (18–22 September 2006). "Earth-grazing fireball on March 29, 2006". European Planetary Science Congress 2006. Berlin. p. 486. Bibcode:2006epsc.conf..486A. Retrieved 2015-03-14.
  58. ↑ Borovička, J.; Ceplecha, Z. (April 1992). "Earth-grazing fireball of October 13, 1990". Astronomy and Astrophysics 257 (1): 323–328. Bibcode:1992A&A...257..323B. ISSN 0004-6361. Retrieved 2015-03-14.
  59. ↑ Spurný, P.; Borovička, J.; Ceplecha, Z.; Shrbený, L. (2008), "Precise Multi-Instrument Data on 45 Fireballs Recorded over Central Europe in the Period 2006-2008" (PDF), Asteroids, Comets, Meteors 2008 held July 14–18, 2008 in Baltimore, Maryland, Bibcode:2008LPICo1405.8217S, retrieved 2015-03-14

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