1 / 9

Cratering in the Solar System

Cratering in the Solar System. Lab 8. Properties of Craters. Craters formed by asteroids and comets able to penetrate the planet’s atmosphere An impactor forms a crater ~20x its own diameter After a crater is formed, it is gradually obliterated by wind or water erosion

gary-norris
Download Presentation

Cratering in the Solar System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Cratering in the Solar System Lab 8

  2. Properties of Craters • Craters formed by asteroids and comets able to penetrate the planet’s atmosphere • An impactor forms a crater ~20x its own diameter • After a crater is formed, it is gradually obliterated by wind or water erosion • On Mars, wind erosion can obliterate a small crater in ~1x106 yrs, large in ~100x106 yrs

  3. Impact Crater

  4. Barringer Meteor Crater, Arizona (50,000 years old) Made by iron meteorite, ~30-100m in diameter, weighing ~60,000 tons, energy released by impact ~3.5 million tons of TNT

  5. Asteroid Signature strip of clay that runs through rocks around the world

  6. NEOs • Pea-size meteoroids – 10/hr • Walnut-size – 1/hr • Grapefruit-size – 1/10 hrs • Basketball-size – 1/month • 50-m rock that would destroy an area the size of NJ – 1/100 yrs • 1-km asteroid – 1/100,000 yrs • 2-km asteroid – 1/500,000 yrs • A "nemesis" parabolic comet impactor would give us a 6-month warning

  7. isochrons Martian Lava Plains

  8. Crater Density and Size • Density • More small craters than large ones, regardless of age of surface • Size • More large craters indicates older surface

  9. Ages • Mercury 4.6 billion years old • Mars 4.6 billion years old • Earth 4.5 billion years old • Moon 4.5 billion years old • http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/index.shtml

More Related