Does Earth Have Impact Craters?
Learning Target
Construct an explanation to describe how geoscience processes have changed Earth's surface at varying time and spatial scales.
Success Criteria
I can make observations of the Moon and Earth to determine similarities and differences.
I can infer the reasons for similarities and differences between the Earth and the Moon.
Questions to Ponder
What are some ways the Earth and moon are similar?
What are some ways the Earth and moon are different?
A Closer Look
Use Google Earth to observe the moon a little bit more closely.
Click on the moon and choose visible.
Observe several craters by zooming into an area.
Compare your observations to your experiments from the previous lesson. How are they similar and different?
Can you infer the conditions in which the craters were created?
Back to Teams...
Describe your observations about the craters on the Moon.
When you looked at the Moon it seemed as if the entire surface was covered with craters. If the Earth has had impacts as well then why don't we seem to have as many?
Investigate
We will use Google Earth to search for potential craters near where you live.
Click on the Google Earth image to the right to get started.
Procedures
Find a familiar landmark such as your home or school. Use the navigation tools to explore the nearby area, searching for evidence of craters.
Stay in your general area!
Record the location of any craters you find using longitude and latitude. Make a sketch of the crater and label it with the parts you find. (refer back to the crater diagram from the previous lesson)
Meteor Crater
Meteor Crater, also known as Barringer Crater, in Arizona, USA is the best preserved crater in the world. It was once thought to be an extinct volcano but was proved to be
The crater was created about 50,000 years ago during the Pleistocene epoch, when the local climate on the Colorado Plateau was much cooler and damper. The area was an open grassland dotted with woodlands inhabited by mammoths and giant ground sloths.
The object that excavated the crater was a nickel-iron meteorite about 160 feet (50 meters) across. The speed of the impact has been a subject of some debate. Modeling initially suggested that the meteorite struck at up to 45,000 mph (20 km/s) but more recent research suggests the impact was substantially slower, at 29,000 mph (12.8 km/s). It is believed that about half of the impactor's bulk was vaporized during its descent through the atmosphere. Impact energy has been estimated at about 10 megatons. The meteorite was mostly vaporized upon impact, leaving few remains in the crater.
Meteor Crater Photos
Scanning For Other Craters
Think about other location on Earth where craters may be more visible. Use Google Earth to investigate as many different areas as you can.
Make a note of any evidence you find that a crater or part of a crater is present. Form a hypothesis as to whether it is an impact crater, volcanic crater, or was formed by some other natural or man-made process.
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How many craters did you find on Earth? How do you know they were craters?
Where are most of the craters that you found? Were they on land or in the water?
Famous Craters of the World
Your teacher will assign you a famous crater to investigate. Locate your crater on Google Earth using the search function, then find out about your crater by doing a brief search on the internet.
Prepare a brief presentation to share your crater with the rest of the class.
Include
name and location of crater
approximately when the crater was formed
what kind of impactor (if known) created the crater
interesting facts about the crater
image of the crater
reference page - at least three resources
List of Famous Craters
Vredefort crater
Sudbury crater
Popigai crater
Manicouagan crater
Acraman crater
Chesapeake Bay crater
Morokweng crater
Kara crater
Beaverhead crater
Haughton crater
Kaali crater
Carancas crater
