2014 AA

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2014 AA
Perihelion
0.9163 AU (137.08 Gm) (q)
1.1623 AU (173.88 Gm) (a)
Eccentricity0.2116 (e)
1.25 yr (457.26 d)
324.1460° (M)
0° 47m 14.244s / day (n)
Inclination1.4156° (i)
101.6086° (Ω)
15 February 2014 (would have been)
52.3393° (ω)
Earth MOID4.54412×10−7 AU (67.9791 km)
Jupiter MOID3.58092 AU (535.698 Gm)
Physical characteristics
Dimensions~3 meters (10 ft)
Mass~4×104 kg (assumed)
30.9[2]

2014 AA was a small

near-Earth asteroid roughly 2–4 meters in diameter that struck Earth on 2 January 2014.[1] It was discovered on 1 January 2014 by Richard Kowalski at the Mount Lemmon Survey at an apparent magnitude of 19 using a 1.52-meter (60 in) reflecting telescope at Mount Lemmon Observatory.[1] 2014 AA was only observed over a short observation arc of about 70 minutes,[1] and entered Earth's atmosphere about 21 hours after discovery.[3] Nonetheless, it remains one of only a few asteroids observed before impact (see Asteroid impact prediction).[4]

Entry

Animation of 2014 AA around the Sun
  Sun ·   Earth ·    2014 AA

Using a

with respect to Earth.[6]

The impactor would have been roughly the size of

shadow cone approximately 40 minutes before entering the atmosphere.[7]

Infrasound was detected by three stations of the Comprehensive Nuclear-Test-Ban Treaty Organization.[8] Peter Brown and Petrus Jenniskens located weak signals from infrasound stations in Bolivia, Brazil and Bermuda.[3] 2014 AA entered Earth's atmosphere around 03:06 ± 5 min UT,[9] 3,000 km from Caracas, Venezuela, far from any landmass.[8][9] No ships or planes reported witnessing the event.[8] A recalculation of the impact parameters of this meteor based on infrasound recordings puts it in the Atlantic Ocean about 1900 km (1030 nautical miles) east of Port of Spain in Trinidad, at a longitude of impact of nearly 44º west and a latitude of 11º north, the impact time being 2456659.618 JD UTC.[10] Extensive numerical simulations indicate that, prior to impact, 2014 AA was subjected to a number of secular resonances and it may have followed a path similar to those of the NEOs 2011 GJ3, 2011 JV10, 2012 DJ54, and 2013 NJ4; NEOs in this transient group experience close encounters with the Earth-Moon system at perihelion and Mars at aphelion and could be a dynamical family.[10]

Other discoveries

Kowalski previously discovered

billion near-Earth objects in the size range of 2014 AA, and impacts of comparably-sized objects occur several times each year.[3]

Several years later, 2018 LA was also discovered by the Mount Lemmon Survey, and ended up impacting Earth in southern Botswana in June 2018.

See also

References

  1. ^
    IAU Minor Planet Center
    . 2 January 2014. Retrieved 2 January 2014. (K14A00A)
  2. ^ a b c "JPL Small-Body Database Browser: (2014 AA)" (last observation: 1 January 2014; arc: 1 day). Jet Propulsion Laboratory. Retrieved 4 April 2016.
  3. ^ a b c d "The First Discovered Asteroid of 2014 Collides With The Earth – An Update". NASA/JPL. 3 January 2014. Archived from the original on 7 January 2014. Retrieved 4 January 2014.
  4. ^ "Tiny Asteroid Discovered Saturday Disintegrates Hours Later Over Southern Africa". NASA/JPL. Jet Propulsion Laboratory. Retrieved 4 June 2018.
  5. ^ "JPL Close-Approach Data: (2014 AA)" (last observation: 1 January 2014; arc: 1 day). Retrieved 2 January 2014.
  6. ^ "2014 AA at 2014-Jan-02 03:04 UT". JPL Horizons. Retrieved 17 January 2021.
  7. ^ Guido, Ernesto (2 January 2014). "Small asteroid 2014 AA hit the Earth's atmosphere". Associazione Friulana di Astronomia e Meteorologia. Retrieved 2 January 2014.
  8. ^ a b c d Beatty, Kelly (2 January 2014). "Small Asteroid 2014 AA Hits Earth". Sky & Telescope. Retrieved 3 January 2014.
  9. ^ .
  10. ^ .

External links