January 3, 2014
Car-Sized New Year’s Asteroid Enters Earth Over Atlantic Ocean
[ Watch the Video: First Asteroid Of 2014 ]
Gerard LeBlond for redOrbit.com - Your Universe Online
According to NASA, the first asteroid of the 2014 season was discovered by Catalina Sky Survey, a NASA-sponsored observatory near Tucson, Arizona. It has been designated as 2014 AA and was viewed moving across the sky early Wednesday morning, January 1, 2014. The size of 2014 AA was estimated to be between seven and 10 feet and had the potential of striking Earth.
The exact path of the object was uncertain, but seemed to be on an impact course with Earth. It most likely entered the atmosphere between 2:00 p.m. Wednesday and 9:00 a.m. Thursday (EST), NASA said in a statement.
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., agree, soon after it was spotted, that 2014 AA would hit the Earth’s atmosphere but the potential location of impact was uncertain. They did concur that the likely range of impact could be from Central America to East Africa. However, according to Chesley, it would most likely impact off the coast of West Africa around 9:00 p.m. EST on January 1.
The experts also believed it would not have survived Earth entry intact, potentially exploding miles above the Earth's surface.
Another asteroid of about the same size, 2008 TC3 completely broke up over northern Sudan in October 2008. Interestingly, asteroid 2008 TC3 was also discovered just prior to entering the Earth’s atmosphere. A few weak signals detected by infrasound stations in the region of the suspected entry are being analyzed to see if there is any connection between them and 2014 AA.
According to Sky and Telescope, Richard Kowalski noticed a blip crossing the screen through northern Orion at 5:16 p.m. on January 1, 2014. He confirmed it was a new find and submitted the information to the IAU’s Minor Planet Center.
At the time of discovery, the object was 300,000 miles from Earth. Peter Brown, from the University of Western Ontario, collected and analyzed the infrasound data. There is a global network of detectors that can pinpoint energy from airbursts and atmospheric detonations.
According to Brown, three stations detected a weak signal, and he was able to connect it to 2014 AA. From this data, Brown was able to pinpoint the asteroid's entry: around 1,900 miles east of Caracas, far away from any landmass.
Brown explains, “The energy is very hard to estimate with much accuracy — the signals are all weak and buried in noise. Had this occurred in the middle of the day I doubt we would see any signals at all.”
It had the explosive power of 500 to 1,000 tons of TNT. Though it sounds like a powerful explosion, the object was about the size of a small car. It seems as though it entered the atmosphere without any eye witnesses and occurred roughly 22 hours after its initial discovery.