Video of the Aug. 21, 2013 Mexican daylight fireball. No sounds were heard by eyewitnesses
On the afternoon of Aug. 21 a fireball strikingly reminiscent of the Great Daylight Fireball of 1972 streaked across the sky near San Luis Potosi in central Mexico. Fortunately, a few people caught its passage with video cameras and cellphones.
Another video of the fireball taking from a moving car
Since there’ve been no reports of falling meteorites, it’s possible the space rock responsible for the spectacular display either skipped off the atmosphere and returned to outer space or fragmented and disintegrated.
The meteor’s speed is amazing. My hunch is in the neighborhood of 40-50,000 mph (56-80,000 km/hr) based upon a similar daylight fireball that etched a chalky streak above the Grand Tetons in Wyoming on Aug. 10, 1972. A tiny asteroid estimated at 10-32 feet (3-10 meters) in diameter entered Earth’s atmosphere over Utah at 50,000 mph that afternoon and traveled some 2,000 miles to a point over central Alberta, Canada. There it bid a fond farewell and returned to space. Easy come, easy go.
Video of the Great Fireball of 1972
Like a rock skipped on a pond, the truck-sized meteoroid briefly skimmed the rarified air 35 miles (57 km) above Earth surface and “landed” back in space to continue an orbit around the sun. To this day, the object known as US19720810, remains an Earth-crosser, though its orbit was changed by the close encounter. The burned and bruised space rock last passed near the planet in August 1997.
How do we know so much about an object that dashed by so briefly so long ago? Beginning in the early 1970s the U.S. Department of Defense (DOD) has kept an eye on missile launches and the like using classified satellites equipped with infrared sensors. These space based eyes also routinely record brilliant fireballs and exploding meteoroids in Earth’s atmosphere.
The 1972 atmospheric impact was the first fireball to be recorded with the new technology. Later analysis showed it was an Apollo-class asteroid first detected at an altitude of about 45 miles (73 km). It dipped as low as 33 miles (53 km) over the Idaho-Montana border before climbing back out of the atmosphere and into space. The entire passage lasted about 100 seconds.
Apollos are Earth-crossing asteroids. The February 15 Russian Chelyabinsk meteor fireball also belonged to the Apollo class. Astronomers have found about 240 of an estimated 2,000 of the largest Earth-grazers, those one kilometer or larger. The bad news (or good news if you like fireballs) is there are about 80 million Apollo-ettes buzzing around out there.
For the latest on the Mexico meteor including more videos, click over to Dirk Ross’s fab Latest Worldwide Meteor / Meteorite News.
** Bright fireball update: A major fireball brighter than the half moon blazed over the southeastern U.S. at about 2:27 a.m. CDT Aug. 28. Sonic booms were heard, and it’s likely meteorites from the breakup of the object reached the ground near Cleveland, Tennessee. Click HERE for photos, a video and updated info.