Lab 4

Other Worlds: crater counting and age estimates.

Previously we compared different areas on one world at a time (the Moon and Mars). This week we will try to determine surface ages for several different planets or other bodies. This can include the Moon or Mars, but at least one should be from another body. The data source for our examples can be the USGS Map-a-planet site, or anywhere else you can find images. For instance, Mercury images can come from the MESSENGER website, or an asteroid or planetary surface from some other site. Use the links to resources in Lab 1

Results can be plotted on this graph (print it) or via a spreadsheet or graphing program - your choice.

The assignment:

1. Find three interesting worlds or places. Any places - they don't all need to be different worlds, but don't go to very small objects like a small asteroid or comet nucleus, they will not have enough craters in our size ranges. You could use cratered and smooth areas of Enceladus as two of your areas, for instance. But do include at least two different worlds. Download the three images. For each one, give location, image dimensions and surface area, and name the region or any individual features if you can find names on a map. Make sure they are different enough to be interesting. Nobody should have the same areas... Also, make sure the area is fairly uniform in its crater density. There would be no point counting craters on an area with half plains and half highlands.

2. For each one, Count craters in the size ranges. Tabulate results. Plot on a paper copy of the graph or via a spreadsheet or graphing program. Summarize your results, estimating ages from the graph and commenting on the results - are they reasonable?

Hand in in two weeks.