2007 VK184

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2007 VK184
The 2014 close approach of 2007 VK184[1]
Discovered by Catalina Sky Survey (703)
Discovery date November 12, 2007
Apollo NEO[3]
Orbital characteristics[3]
Epoch 2014-May-23
(JD 2456800.5)
Aphelion 2.7104 AU
Perihelion 0.74227 AU
1.7263 AU
Eccentricity 0.57003
828.49 d (2.27 yr)
15.6 km/s
Inclination 1.2225°
Physical characteristics
Dimensions ~130 meters (430 ft)[4]
Mass 3.3×109 kg (assumed)[4]
~0.065 meters (2.6 in) per second

2007 VK184 (also written 2007 VK184) is an Apollo near-Earth asteroid estimated to be about 130 meters (430 ft) in diameter.[4] It was listed on the Sentry Risk Table with a Torino Scale rating of 1.[4] A Torino scale rating of 1 is a routine discovery in which a pass near the Earth is predicted that poses no unusual level of danger.[5] 2007 VK184 was discovered on November 12, 2007, by the Catalina Sky Survey.[2] It was recovered on March 26, 2014 by Mauna Kea,[6][7] and removed from the Sentry Risk Table on March 28, 2014.[8]

By January 4, 2008, with an observation arc of 52 days, there was a 1 in 2700 chance of an impact with Earth on June 3, 2048.[9]

The Sentry Risk Table, using an observation arc of 60 days, showed the asteroid had a 1 in 1820 chance (0.055%) of impacting Earth on June 3, 2048.[4] Since the March 2014 recovery, it is known that the asteroid will pass 0.013 AU (1,900,000 km; 1,200,000 mi) from Earth on June 2, 2048.[1]

2014 passage[edit]

Before the 2014 close approach, the asteroid had a modest observation arc of 60 days,[4] and the imprecise trajectory of this asteroid was complicated by close approaches to Earth, Venus and Mars.[1] On May 23, 2014, the asteroid passed 0.17 AU (25,000,000 km; 16,000,000 mi) from Earth[1] and reached an apparent magnitude of ~20.8.[10] As expected the close approach allowed astronomers to recover the asteroid on March 26, 2014 and refine the odds of a future collision.[7] As the asteroid gets closer to Earth, the positional uncertainty becomes larger.[11] By recovering the asteroid well before closest approach you can avoid searching a larger region of the sky.[11] Most asteroids rated 1 on the Torino Scale are later downgraded to 0 after more observations come in.

Risk assessments were calculated based on a diameter of 130 meters.[4] It was estimated that, if it were ever to impact Earth, it would enter the atmosphere at a speed of 19.2 km/s and would have a kinetic energy equivalent to 150 megatons of TNT.[4] Assuming the target surface is sedimentary rock, the asteroid would impact the ground with the equivalent of 40 megatons of TNT and create a 2.1 kilometers (1.3 mi) impact crater.[12] Asteroids of approximately 130 meters in diameter are expected to impact Earth once every 11000 years or so.[12]

On March 26–27, 2014, additional observations were made which ruled out the chance of an impact in 2048.[11]

See also[edit]

  • 99942 Apophis, a NEO that, for a few days, was thought to have a slight probability of striking the Earth in 2029. But the likelihood that would happen was quickly determined to be zero.


  1. ^ a b c d "JPL Close-Approach Data: (2007 VK184)" (last observation: 2014-03-27; arc: 6.37 years). Retrieved 2014-04-01. 
  2. ^ a b "MPEC 2007-V94 : 2007 VK184". IAU Minor Planet Center. 2007-11-13. Retrieved 2010-10-27. 
  3. ^ a b c d "JPL Small-Body Database Browser: (2007 VK184)" (last observation: 2014-03-27; arc: 6.37 years). Jet Propulsion Laboratory. Retrieved 2014-04-01. 
  4. ^ a b c d e f g h "2007 VK184 Earth Impact Risk Summary". Wayback Machine:NASA/JPL Near-Earth Object Program Office. 2013-10-17. Retrieved 2014-04-01. 
  5. ^ "The Torino Impact Hazard Scale". NASA/JPL Near-Earth Object Program Office. 13 Apr 2005. Retrieved 2011-11-05. 
  6. ^ "MPEC 2014-F50 : 2007 VK184". IAU Minor Planet Center. 2014-03-28. Retrieved 2014-04-01. 
  7. ^ a b "2007 VK184 Orbit". IAU Minor Planet Center. Retrieved 2014-04-01. 
  8. ^ "Date/Time Removed". NASA/JPL Near-Earth Object Program Office. Retrieved 2014-04-01. 
  9. ^ "WayBack Machine archive from 10 Jan 2008". Wayback Machine. 2008-01-10. Retrieved 2013-02-20. 
  10. ^ "2012 VK184 Ephemerides for 23 May 2014". NEODyS (Near Earth Objects – Dynamic Site). Retrieved 2013-02-21. 
  11. ^ a b c "Asteroid 2007 VK184 Eliminated as Impact Risk to Earth". NASA/JPL Near-Earth Object Program Office. 2014-04-02. Retrieved 2014-04-03. 
  12. ^ a b Robert Marcus; H. Jay Melosh & Gareth Collins (2010). "Earth Impact Effects Program". Imperial College London / Purdue University. Retrieved 2013-02-20.  (solution using 130 meters, 2600 kg/m3, 19.2 km/s, 45 degrees, Target: Sedimentary Rock)

External links[edit]