Early Wednesday morning (Jan. 1, 2014), while New Year's 2014 celebrations were
still underway in the United States, the Catalina Sky Survey near Tucson, Ariz.,
collected a single track of observations with an immediate follow-up on what was
possibly a very small asteroid -- 7 to 10 feet (2 to 3 meters) in size -- on a
potential impact trajectory with Earth.
Designated 2014 AA, which would make it the first asteroid discovery of 2014,
the track of observations on the object allowed only an uncertain orbit to be
calculated. However, if this was a very small asteroid on an Earth-impacting
trajectory, it most likely entered Earth's atmosphere sometime between 11 a.m.
PST (2 p.m. EST) Wednesday and 6 a.m. PST (9 a.m. EST) Thursday.
Using the only available observations, three independent projections of the
possible orbit by the independent orbit analyst Bill Gray, of the Minor Planet
Center in Cambridge, Mass., and Steve Chesley, of NASA's Near-Earth Object
Program Office at the Jet Propulsion Laboratory in Pasadena, Calif., are in
agreement that 2014 AA would hit Earth's atmosphere. According to Chesley, the
potential impact locations are widely distributed because of the orbit
uncertainty, falling along an arc extending from Central America to East Africa.
The most likely impact location of the object was just off the coast of West
Africa at about 6 p.m. PST (9 p.m. EST) Jan. 1.
It is unlikely asteroid 2014 AA would have survived atmospheric entry intact,
as it was comparable in size to asteroid 2008 TC3, which was about 7 to 10 feet
(2 to 3 meters) in size. 2008 TC3 completely broke up over northern Sudan in
October 2008. Asteroid 2008 TC3 is the only other example of an object
discovered just prior to hitting Earth. So far, there have been a few weak
signals collected from infrasound stations in that region of the world that are
being analyzed to see if they could be correlated to the atmospheric entry of
2014 AA.
NASA's Near-Earth Object Program at NASA Headquarters, Washington, manages
and funds the search, study and monitoring of asteroids and comets whose orbits
periodically bring them close to Earth. JPL manages the Near-Earth Object
Program Office for NASA's Science Mission Directorate in Washington. JPL is a
division of the California Institute of Technology in Pasadena.
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