Saturday, December 6, 2008

Meteorites

Meteors are tiny meteoroids that burn up as they travel through the earth's atmosphere producing tiny streaks of light. Meteorites are meteoroids that reach the surface of earth without being fully burnt. The meteoroid material is left by comets as they pass close to the Sun.



More than 3,000 meteorites land on Earth every year. Most fall in the sea, but a handful are seen to fall on the land.



The fragmentation of the meteorite causes a visual effect called a shooting star.

Willamette Meteorite





Meteorites from mars

Atleast eight meteorites have fallen on theEarth from the Mars. The Nakhla meteorite fell in Egypt in 1911. Those meteorites tell us that the Mars had once running water.




There are atleast three main types of meteorites: stony, iron, or stony-iron.
The stony meteorites contain silicate minerals.They are subdivided into Chondrites and Achondrites meteorites


Chondrite meteorite


Achondrite Meteorite


The Iron meteorites contain a high percentage of iron and nickel. They are created in the rupture of asteroids.



Iron meteorite


Stony-iron meteorite

Gao Meteorite

The Hoba meteorite, the largest in the world was found in Nambia in 1920. It measures 2.73x 2.43 and is 82 percent iron and 16 percent nickel. It weighs more than 60 tonnes.


Hoba Meteorite


The Tent, found in Greenland in 1894, originally known by its Eskimos name, as Ahnighito. This meteorite weighs about 57.3 tonnes. One can view this meteorite, it the New York Museum of Natural History.

Ahnighito

Large meteorites can form a crater when they strike the Earth.


Vredefort, South Africa


Chicxulub, Yucatan, Mexico

The collisionof the meteorite compresses and excavates the ground, leaving a crater.




The Popigai crater in Siberia, Russia is the fourth largest impact crater on the earth.


Popigai, Russia

Today about 150 impact craters can be identified including the Wolfe Crater of Australia.

1 comment:

Anonymous said...

can meteorites be sold for money??