Meteoroids

THE TUNGUSKA EVENTThough it flattened all the trees in every direction for 30 miles, the

airburst that took place over Siberia's Tunguska River left no crater behind. Scientists theorize that the blast, caused probably by a meteor or comet fragment that exploded a few miles over the

surface of the Earth, was 1000 times as powerful as the bomb that fell on Hiroshima, Japan .

OTHERWORLDLY OBJECTIt is believed that the Willamette meteorite crashed to the Earth somewhere in Canada, but that it was shifted by a

glacier south to Oregon, where it was discovered in 1902. It is the largest meteorite found in the United

States, and the sixth largest in the world .

IMPACT CRATERGosses Bluff, near Alice Springs, Australia was

formed by the impact of a meteor or comet about 143 million years ago. It is one of the

approximately 170 terrestrial impact craters on the Earth's surface .

HOLE IN THE DESERTMuch smaller and younger than Gosses Bluff, Arizona's

Meteor Crater is also known as Barringer Crater, in honor of Daniel Barringer, the man who first suggested it was formed by the collision of a meteor with the Arizona

desert around 50,000 years ago .

CURIOSITYTwo Saudi men examine a two-ton meteorite embedded

in the sand of the Kingdom's desolate Empty Quarter .• •

METEOR SHOWERA time-lapse photograph captures the trails of two meteors in the

sky over Amman, Jordan. The red streaks at the mid left and bottom right are meteors; the white streaks are stars. Most meteors

disintegrate in the intense heat created from entering the Earth's atmosphere .

RING SHAPED RESERVOIRWater from a series of hydroelectric projects has filled

Manicougan Crater in northern Quebec to brimming. The resulting lake and the island in its middle are sometimes

called the "eye of Quebec".

VAST EXPANSEIt is believed that when Gosses Bluff crater was originally

formed, it measured over 13.5 miles in diameter. After 143 million years, much of it has eroded away, leaving

an exposed 3-mile wide formation .

CLOSE ENCOUNTERThe Ahnighito Meteorite, at New York's American Museum of Natural History, is one part of a much

larger meteorite that fell to Earth (landing in Greenland) thousands of years ago. Even so, at 34 tons, it is the second largest meteorite in the world .