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.
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).

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 do 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]

A list of examples of known close approaches.[note 1] (see also NEO Earth Close Approaches)

Date of
closest approach
Object Nominal geocentric
distance (km)[note 2]
Size (m)
(approximate)
October 29, 2013 2013 UV3 283,000 11 - 25
October 25, 2013 2013 UX2 150,000 3.8 - 8.4
February 15, 2013 367943 Duende[2][3] 34,100 40×20[4]
October 12, 2012 2012 TC4[5] 95,000 17
May 29, 2012 2012 KT42 20,800 4–10
May 28, 2012 2012 KP24[6][7] 57,300 25
January 27, 2012 2012 BX34 65,400 8
December 3, 2011 2011 XC2 347,000 100
November 8, 2011 (308635) 2005 YU55 324,900 400
June 27, 2011 2011 MD[8][9] 18,700 10
February 4, 2011 2011 CQ1[10] 11,900 1
October 9, 2008 2008 TS26[11] 12,500 1

The average distance to the Moon is about 384,400 km[12]

For lists of close approaches less than one lunar distance from Earth for a given year:

Earth-grazers[edit]

Distance
(km)
Size (m)
(approximate)
Date of
closest approach
Object
0 mean sea level
57 2–10 August 10, 1972 1972 Great Daylight Fireball
circa 100 circa 1 between October 13, 1990,
and August 7, 2007
three Earth-grazing fireballs
100 Kármán line

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.

Small asteroids[edit]

Asteroids smaller than about 50 meters:[13]

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[10]
0.000084 12,500 1 October 9, 2008 2008 TS26[11]
0.000086 12,900 6 March 31, 2004 2004 FU162
0.000125 18,700 10 June 27, 2011 2011 MD[8][9]
0.000137 20,400 7 November 6, 2009 2009 VA
0.000139 20,800 4–10 May 29, 2012 2012 KT42
0.00018 27,000 3 December 23, 2013 2013 YB[14]
0.000228 34,100 40×20[4] February 15, 2013 367943 Duende[2][3]
0.000260 38,900 3 November 17, 2010 2010 WA[15]
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[6][7]
0.000437 65,400 8 January 27, 2012 2012 BX34
0.000482 72,100 9 September 8, 2010 2010 RK53[16]
0.000483 72,200 19 March 2, 2009 2009 DD45
0.000484 72,400 2–7 December 11, 2013 2013 XS21[17]
0.000531 79,400 7 September 8, 2010 2010 RF12[18]
0.000564 84,300 5 September 27, 2003 2003 SQ222[19]
0.000568 85,000 15 March 18, 2009 2009 FH[20]
0.000635 95,000 17 October 12, 2012 2012 TC4[21]
0.000704 105,400 10 December 9, 1994 1994 XM1[22][23]
0.000862 129,000 15–30 January 13, 2010 2010 AL30
0.000998 149,200 7 May 20, 1993 1993 KA2[22][24]
0.001124 168,200 6–10 January 18, 1991 1991 BA
0.001539 230,200 47 April 1, 2012 2012 EG5[25]
0.001655 247,600 12 September 8, 2010 2010 RX30[26]
0.00257 384,400 average distance to the Moon[12]
0.002899 433,600 22 April 9, 2010 2010 GA6

Asteroids[edit]

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

Asteroids larger than about 50 meters:[13][27]

Nominal geocentric
distance (AU)
Nominal geocentric
distance (km)
Size (m)
(approximate)
Date of
closest approach
Object
0.00155* 233,000 500 December 31, 1914 (152680) 1998 KJ9
0.00159* 239,000 200 April 11, 1971 2002 JE9
0.002172 324,900 360 November 8, 2011 2005 YU55
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[12]
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 2007 PA8[28][29]
0.046332 6,900,000 5400 December 12, 2012 4179 Toutatis[30][31]

* 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:[32]

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
0.001572 235,200 170–370 January 2, 2101 2007 YV56[33]
0.001585 237,000 360±40 November 8, 2075 (308635) 2005 YU55
0.001663 248,800 700–1500 June 26, 2028 (153814) 2001 WN5
0.001980 296,200 170–370 January 22, 2148 85640 (1998 OX4)[34]
0.002222 332,500 190–250 May 28, 2065 2005 WY55
0.00257 384,400 average distance to the Moon[12]

A list of predicted NEO approaches at larger distances is maintained as a database by the NASA Near Earth Object Program.[35]

** 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]

Furthermore, 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.

Notes[edit]

  1. ^ A more complete listing of near-Earth asteroids is published by the International Astronomical Union: "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.

References[edit]

  1. ^ Responding to Potential Asteroid Redirect Mission Targets
  2. ^ a b "NEOs Removed from Impact Risk Tables". Near-Earth Object Program Office. NASA/JPL. Retrieved 17 February 2013. 
  3. ^ a b "JPL Small-Body Database Browser: (2012 DA14)". 2013-02-16 last obs. Retrieved 17 February 2013. 
  4. ^ a b Benner, Lance A. M. "2012 DA14 Goldstone Radar Observations Planning". Asteroid Radar Research. JPL/California Institute of Technology. Retrieved 20 February 2013. 
  5. ^ Malik, Tariq (11 October 2012). "House-Size Asteroid Comes Closer to Earth Than the Moon Friday: Watch Live". SPACE.com. Retrieved 10 February 2013. 
  6. ^ a b "JPL Small-Body Database Browser: (2012 KP24)". 2012-05-28 last obs. Retrieved 16 February 2013. 
  7. ^ a b Plait, Phil (25 May 2012). "Small asteroid to buzz Earth on May 28". Discover. Retrieved 16 February 2013. 
  8. ^ a b "JPL Small-Body Database Browser: (2011 MD)". 2011-07-03 last obs. Retrieved 22 February 2013. 
  9. ^ a b Benner, Lance A. M. "2011 MD Goldstone Radar Observations Planning". Asteroid Radar Research. JPL/California Institute of Technology. Retrieved 22 February 2013. 
  10. ^ a b 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. 
  11. ^ a b "JPL Small-Body Database Browser: (2008 TS26)". 2008-10-09 last obs. Retrieved 12 February 2013. 
  12. ^ a b c d NASA Staff (10 May 2011). "Solar System Exploration: Planets: Earth's Moon: Facts & Figures". NASA. Retrieved 6 November 2011. 
  13. ^ a b "Closest Approaches to the Earth by Minor Planets". International Astronomical Union/Minor Planet Center. Retrieved 12 February 2013. 
  14. ^ "JPL Small-Body Database Browser: (2013 YB)". 2013-12-23 last obs. Retrieved 2013-12-24. 
  15. ^ "JPL Small-Body Database Browser: (2010 WA)". 2010-11-17 last obs. Retrieved 12 February 2013. 
  16. ^ "JPL Small-Body Database Browser: (2010 RK53)". 2010-09-17 last obs. Retrieved 1 March 2013. 
  17. ^ "JPL Small-Body Database Browser: (2013 XS21)". 2013-12-14 last obs. 
  18. ^ "2010 RF12 Earth Impact Risk Summary". Near-Earth Object Program Office. NASA/JPL. Retrieved 12 February 2013. 
  19. ^ "JPL Small-Body Database Browser: (2003 SQ222)". 2003-10-02 last obs. Retrieved 12 February 2013. 
  20. ^ "JPL Small-Body Database Browser: (2009 FH)". 2009-03-18 last obs. Retrieved 1 March 2013. 
  21. ^ "JPL Small-Body Database Browser: (2012 TC4)". 2012-10-11 last obs. Retrieved 12 February 2013. 
  22. ^ a b Williams, David R. "Near Earth Object Fact Sheet". Lunar & Planetary Science. NASA Goddard Space Flight Center. Retrieved 17 February 2013. 
  23. ^ "JPL Small-Body Database Browser: (1994 XM1)". 1994-12-09 last obs. Retrieved 17 February 2013. 
  24. ^ "JPL Small-Body Database Browser: (1993 KA2)". 1993-05-22 last obs. Retrieved 17 February 2013. 
  25. ^ "JPL Small-Body Database Browser: (2012 EG5)". 2012-04-03 last obs. Retrieved 1 March 2013. 
  26. ^ "JPL Small-Body Database Browser: (2010 RX30)". 2010-09-08 last obs. 
  27. ^ "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 15 November 2011. 
  28. ^ Benner, Lance A. M. "(214869) 2007 PA8 Goldstone Radar Observations Planning". Asteroid Radar Research. JPL/California Institute of Technology. Retrieved 14 February 2013. 
  29. ^ "JPL Small-Body Database Browser: 214869 (2007 PA8)". 2013-02-13 last obs. Retrieved 15 February 2013. 
  30. ^ "JPL Small-Body Database Browser: 4179 Toutatis (1989 AC)". 2012-12-08 last obs. Retrieved 12 February 2013. 
  31. ^ Atkinson, Nancy (11 December 2012). "Two Asteroids Will Buzz Past Earth on December 11". Universe Today. Retrieved 12 February 2013. 
  32. ^ "PHA Close Approaches To The Earth". International Astronomical Union/Minor Planet Center. Retrieved 14 November 2011. 
  33. ^ "JPL Small-Body Database Browser: (2007 YV56)". 2012-01-29 last obs. Retrieved 17 February 2013. 
  34. ^ "JPL Small-Body Database Browser: 85640 (1998 OX4)". 2008-07-29 last obs. Retrieved 17 February 2013. 
  35. ^ 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)

External links[edit]