The close fly-by of an asteroid like DA14, like the Tunguska meteor, is a once-in-1, 000-years event.
It's also unlikely that this event would happen within 3, 000 miles of the Tunguska impact.
The close fly-by of an asteroid like DA14, like the Tunguska meteor, is a once-in-100-years event.
For sky-watchers, the reports bring to mind the famous Tunguska event of 1908 in remote Siberia.
Regardless, researchers are hoping that the Tunguska event can help them better prepare for future meteor collisions.
This Asteroid did not even hit the Ground and this is known by most as the TUNGUSKA EVENT.
The object appears to have approached Tunguska from the southeast at about 11 km per second (7 miles a second).
In 1908 a comparatively tiny piece of space-borne rock, 30-50 metres across, exploded above Tunguska, a remote part of Siberia.
It is the largest reported meteor since the one that hit Tunguska, Siberia, in 1908, according to the U.S. National Aeronautics and Space Administration.
But even if Spaceguard does succeed, another problem remains smaller asteroids, of the size believed to have caused a huge explosion above Tunguska, in Russia, in 1908.
ECONOMIST: A large asteroid sweeps by Earth. Where are the others?
"In terms of things we have observed, this is the largest since Tunguska, " Brown said, referring to the suspected meteor that flattened a Siberian forest in 1908.
The "Tunguska Event" that flattened over 800 square miles of Siberian forest in 1908 was caused by a stony asteroid only 50 meters in diameter exploding in the lower atmosphere.
Apophis is some 350 metres across, considerably larger than the object that is thought to have flattened 2, 000 square kilometres of Siberian forest as it vaporised in the atmosphere above Tunguska in 1908.
While 1km-size and bigger asteroids are thought to hit only once every 500, 000 years, on average, rocks 50-100 metres across, like the Tunguska object, are thought to hit the planet once every thousand years.
ECONOMIST: A large asteroid sweeps by Earth. Where are the others?
For sky watchers, the reports bring to mind the famous Tunguska event of 1908 in remote Siberia, in which an asteroid entered the atmosphere and exploded, leveling trees over an area of 820 square miles -- about two-thirds the size of Rhode Island.
Siberia time in the morning in June of the year 1908 high in the sky above the Forest in the remote wilderness of Tunguska Siberia heard an explosion that laid flat more than 800 square miles of the forest with all the trees pointing away from the center of the blast with most all the trees laying on their side.
If asteroids as big as DA14 pass close to Earth once every decade or two, and meteors as large as the Chelyabinsk one impact once every 100 years (a similar meteor having caused the Tunguska event in 1908), the chance of both events happening on any one day are indeed very small: 1 in 3, 650 days times 1 in 36, 500 days, or about 1 in 100 million -- not odds you would bet against.
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