Week 3 (8 Oct): Assignment 4

What is the impact crater and lunar-like volcanic feature closest to where you live. How do those features compare to ones on the Moon? Bigger? Smaller? Different erosional state? What questions do you have about any lunar feature?

Ans: The closest impact crater to me (Washington DC region) is the Chesapeake Bay Impact Crater formed about 35 million years ago. Although it is a well preserved (complex) crater, it has only been recently recognized since it is covered by 35 million years of sediment. SSA Greg Redfern gave a presentation about the crater at the VAAS meeting this past Saturday. Although there were many clues, some dating back to the Civil War, it wasn't until some oil companies released their seismic data and all the pieces fell into place. In 2005, they made a core drilling. The crater is about 53 miles (90km) in diameter making it the 7th largest. This makes it just a little smaller than Copernicus (93km) but is about the same size as Petzval, Hertz, Heraclitus to name a few...

Some links about the crater:

Earth Impact Database -- currently at 174 craters
USGS: Gazetteer of Planetary Nomenclature: The Moon -- Useful website for finding sizes of craters and other lunar features

Random weird link that I found about moon craters... Moon Crater Simulator... not sure of its purpose...

As for volcanic features, that's a bit tougher to pinpoint. I guess that the nearest volcano is either Yellowstone or one of the ones in the West Indies or Iceland (in terms of distance from DC region). There are some hot springs in Bath County, VA. Not sure if those count though.

Websites about volcanoes:

===My Questions ===(I know the answers to some, but raise them anyway as something to think about since those questions are not obvious...)
  • Why are the maria mainly on one side of the moon?
  • On Earth, notice how there are "no" craters in the jungle regions of South America, Africa and Asia. Why not?