Peru Meteorite could have survived descent if it lacked internal cracks and irregularities

ANI

Tue, 01 Jan 2008: 

London, July 4 (ANI): Scientists have said that a meteorite that crashed in Peru in September last year may have survived the descent towards Earth if, by a one-in-a-million chance, it lacked internal cracks and irregularities.

 

According to a report in New Scientist, the Carancas meteorite struck the to of that name in Peru last September, blowing a hole in the ground 13 metres wide.

 

The fact that locals saw a single object strike suggests a meteorite made of iron, like the one that created a similar crater in 1990 in Sterlitamak, Russia, because stony meteorites normally fragment high above the Earth and spread relatively harmlessly over a wide area.

 

However, the debris found by investigators was stone.

 

"Stony meteorites normally fragment high up above the Earth and spread harmlessly over a wide area," said the researchers.

 

One explanation for this conundrum, though at odds with the eyewitness accounts, is that the object broke into smaller pieces, which hit the ground together.

 

Another theory is that the meteorite was one of many chunks from a larger, slow-moving object which broke up when it met the atmosphere at a glancing angle. Yet all these chunks would probably have been traveling too slowly to create the Carancas crater.

 

Now, Pavel Spurny and colleagues at the Astronomical Institute of the Academy of Sciences of the Czech Republic argue that the object could have survived the descent intact if, by a one-in-a-million chance, it lacked internal cracks and irregularities.

 

Using estimates from other groups of the meteorite's trajectory, velocity and impact energy, Spurny and colleagues built a computer model showing that an object around 1 metre across could enter the atmosphere at a relatively fast 20 kilometres per second and survive the descent if it was free of cracks. (ANI)