By Timothy Kusky
ISBN-10: 0816064695
ISBN-13: 9780816064694
Asteroids and comets are area items that orbit the solar. This publication examines the various craters in the world that experience shaped due to meteorites or asteroids crashing into the planet, excavating large holes and wreaking common destruction at the panorama.
Read Online or Download Asteroids and Meteorites: Catastrophic Collisions With Earth (The Hazardous Earth) PDF
Similar science & technology books
New PDF release: Focus on Physical Science: Grade 8, California
Specialize in actual technological know-how Grade eight, California [Glencoe/Mcgraw-Hill,2007] [Hardcover]
Download PDF by Sean McCollum: Volcanic Eruptions, Earthquakes, And Tsunamis (Scientific
Explores the underground reasons of traditional failures and exhibits how scientists search to avoid wasting lives via figuring out of Earth's wild and stressed geology.
- Holt Science & Technology: Astronomy: Short Course J
- Germ Hunter: A Story About Louis Pasteur (Creative Minds Biography)
- Food (Experimenting With Everyday Science)
- Tornadoes
Additional resources for Asteroids and Meteorites: Catastrophic Collisions With Earth (The Hazardous Earth)
Example text
6 miles (1 km) are orbiting the Sun between Mars and Jupiter. They may get pushed into Earth-crossing orbits after being deflected by collisions in the asteroid belt or by gravitational perturbations during complex orbital dynamics. Spectral measurements of some of the asteroids show that they have compositions that correlate with the meteorites sampled on Earth, and a crude gradation of compositions in the asteroid belt is thought to represent both the original distribution of different parent bodies that broke up during collisions, and the initial compositional trends across the solar nebula.
Examples of simple craters include the Barringer Meteor Crater in Arizona, and Roter Kamm in Namibia. Complex craters are larger, generally greater than two miles (3 km) in diameter. They have an uplifted peak in the center of the crater, and have a series of concentric rings around the excavated core of the crater. Examples of complex craters include Manicougan, Clearwater Lakes, and Sudbury in Canada; Chicxulub in Mexico; and Gosses Bluff in Australia. The style of impact crater depends on the size of the impacting meteor, the speed at which it strikes the surface, and to a lesser extent the underlying geology and the angle at which the meteor strikes Earth.
The moon and other planets show much greater densities of impact craters, and since Earth has a greater gravitational pull than the moon, it should have been hit by many more impacts than the moon. Meteorite impact craters have a variety of forms but are of two basic types. Simple craters are circular bowl-shaped craters with overturned rocks around their edges, and are generally less than three miles (5 km) in diameter. They are thought to have been produced by impact with objects less than 100 feet (30 m) in diameter.
Asteroids and Meteorites: Catastrophic Collisions With Earth (The Hazardous Earth) by Timothy Kusky
by Steven
4.0