Introduction: Meteorites are the oldest and most distant objects of our solar system that have been available for scientists to study. They came to us from the asteroid belt, about 2.8 AU out, between the orbits of Mars and Jupiter. Essentially they remain unchanged since their formation. Samples from both the Earth and the Moon are younger. So these essentially hold within them, the secrets of creation (of the solar system.) By studying them we unlock that information and get a glimpse into the beginning of the solar system. Your job is three fold:

1. View the NASA Slide - Tape presentation JSC 742, Meteorites - Rocks from Space
2. Examine the samples before you and describe them. For your help a brief introduction to them is attached with space to complete your description.
3. Complete the Activity Sheet.

Achondrite - Norton County

This is part of the huge stony meteorite that fell in Norton County, Kansas in 1946. It is primarily magnesium rich silicate (MgSiO₃ ) with no iron present.

This fell near Pueblito de Allende, Chihuaha, Mexico on February 8, 1969. Three tons so far have been recovered. We think the chondrules were formed at high temperatures and the matrix of cementing material came together at a lower temperature. The dark carbonaceous chondrites contain concentrations of organic compounds.

This was found in Texas in 1883. It is hard and dense and seems resistant to oxidation. It is a "high-iron" chondrite. The chondrules are difficult to see.

This is a well known event. The Holbrook Meteor Shower struck the ground near Holbrook, Arizona in July 1912. The cut side of the sample that is light colored showws us pieces of iron-nickel. This is a "low-iron" meteorite.

Iron Meteorite - El Sampal

This is a sample found in Argentina in 1973. One side has been polished and etched with acid to show the Widmanstatten pattern. Kamacite and Taenite are minerals formed as the nickel-iron cooled. These minerals are not uncommon in meteorites but not found in Earth rocks.

Pallasite - Admire

This was found near Admire, Kansas. Pallasites are stony-iron meteorites with equal amounts of iron-nickel and silicate minertal olivine. Similar materials are believed to exist in the iron core and silicate mantle of planets.

1. Rocks that fall to the earth from space are called ____________________________________.

2. As they approach the Earth they are called ___________________________________.

3. The light effect produced as they pass through the atmosphere is called a ____________________________________.

4. Most meteorites originate in the ______________________________________________.

5. The age of meteorites is approximately ______________________________________________.

6. Meteoroids that break up in the atmosphere produce _____________________________________________.

7. Very large meteoroids produce _________________________________________ about ___________________ times their diameter upon impact with the Earth.

8. __________________________ people have been killed by meteorites.

9. The most common type of meteorite is the ________________________________________________.

10. The most commonly found kind of meteorite is the ___________________________________________.

11. About ________________ meteorites fall each year in the United States.

12. Meteorites can come from other planets as well, including the one from Mars. How could we know it came from Mars?

Credit: Many of the ideas and information for this activity are taken from the NASA materials accompanying the Meteorite Sample Disc. Thanks to NASA Johnson Center in Houston.