2007 VK184

2007 VK184

The 2014 close approach of 2007 VK184[1]
Discovery[2]
Discovered by Catalina Sky Survey (703)
Discovery date November 12, 2007
Designations
Apollo NEO[3]
Orbital characteristics[3]
Epoch 2014-May-23
(JD 2456800.5)
(Uncertainty=1)[3]
Aphelion 2.7104 AU
Perihelion 0.74227 AU
1.7263 AU
Eccentricity 0.57003
828.49 d (2.27 yr)
15.6 km/s
338.50°
Inclination 1.2225°
253.96°
73.159°
Physical characteristics
Dimensions ~130 meters (430 ft)[4]
Mass 3.3×109 kg (assumed)[4]
~0.065 meters (2.6 in) per second
22.0[3]

    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

    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

    References

    1. 1 2 3 4 "JPL Close-Approach Data: (2007 VK184)" (last observation: 2014-03-27; arc: 6.37 years). Retrieved 2014-04-01.
    2. 1 2 "MPEC 2007-V94 : 2007 VK184". IAU Minor Planet Center. 2007-11-13. Retrieved 2010-10-27.
    3. 1 2 3 4 "JPL Small-Body Database Browser: (2007 VK184)" (last observation: 2014-03-27; arc: 6.37 years). Jet Propulsion Laboratory. Retrieved 2014-04-01.
    4. 1 2 3 4 5 6 7 8 "2007 VK184 Earth Impact Risk Summary". Wayback Machine:NASA/JPL Near-Earth Object Program Office. 2013-10-17. Archived from the original on October 17, 2013. 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. 1 2 "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. Archived from the original on January 10, 2008. Retrieved 2013-02-20.
    10. ↑ "2012 VK184 Ephemerides for 23 May 2014". NEODyS (Near Earth Objects – Dynamic Site). Retrieved 2013-02-21.
    11. 1 2 3 "Asteroid 2007 VK184 Eliminated as Impact Risk to Earth". NASA/JPL Near-Earth Object Program Office. 2014-04-02. Retrieved 2014-04-03.
    12. 1 2 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

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