The Mineral Museum on the campus of Montana Tech in Butte has displays of meteorites. Meteorites are thought to originate in the Asteroid Belt, located between the orbits of Mars and Jupiter. Occasionally, objects from the Asteroid Belt come close enough to get caught in earth’s gravity. When they travel through the earth’s atmosphere they are known as meteors. As they travel through the atmosphere, they are heated to extreme temperatures which causes the outer surface to melt off and produce the thumbprint feature which resembles thumbprints made in soft clay. Meteors which survive the trip through the atmosphere and strike the surface of the earth are known as meteorites.
Tektites
Tektites look like volcanic glass or obsidian but they are not formed by volcanic activity. According to the display:
“There are two schools of thought on the origin of tektites. Some scientists think that they are from the moon and were produced from material rejected from the lunar surface by meteor impacts. Others give evidence for tektites having been produced by meteor impacts on the earth’s surface.”
Nickel-Iron Meteorites
Nickel-iron meteorites are composed of nickel-iron alloys. This means that they are two or three times heavier than a typical rock of comparable size. These are the most frequently found meteorites.
Pallasite Meteorites
Only about 1% of all meteorites are pallasites: that is, they contain large crystals of the mineral olivine in an iron-nickel matrix.
Stony Meteorites
Stone meteorites are composed of silicate minerals and look much like ordinary rock.
Shown above is the Twodot Meteorite. The original meteorite weighed 21,400 grams while the cut slab shown above weighs on 66.85 grams.
Mistaken Meteorites
There are some objects which, at first glance, look like meteorites but upon closer examination are found to be either human-made or naturally occurring objects.
New Museums Group
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More museum photo tours:
Mineral Museum: Butte Minerals (Photo Diary)
Museums 101: Hall of African Mammals (Photo Diary)
National Museum of Scotland: Discoveries (Photo Diary)
Museums 101: The Chinese in British Columbia (Photo Diary)
Museums 101: Hagerman Valley Historical Museum (Photo Diary)
Museums 101: The Presby House Kitchen (Photo Diary)
Veterans Memorial Museum: Women in World War II (Photo Diary)
Museums 101: The Parlor at the Fort Dalles Museum (Photo Diary)