Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS
Rough Science Photo of the Rough Science cast
 Home | Death Valley | Scientists | Mike | Communication Diary - Day 3
Series 4:
Death Valley
Aerial Surveyor
The Scientists
Director's Notes
Producer's Notes
Tune In
Series 1:
Series 2:
Series 3:
New Zealand
About the Show
Discover More
Site Map
spacer spacer spacer
Mike's Communication Diary Day 1&2 3

Day Three

By the middle of day three I’ve got enough data points to be able to plot a graph of log (crater diameter) against log (energy of impact). Using Kathy and Iain’s estimate of the diameter of the real Nevada impact crater, we will be able to extrapolate from my graph in order to determine the energy of the meteorite that caused it. Knowing the impact energy, and the approximate speed of impact (which we can guestimate), will give us the mass of the meteorite. If we also guestimate the density of the meteorite (most of them are composed of iron and nickel, so a reasonable estimate should be possible), we can work out the volume of the meteorite. From there it’s easy enough to calculate its diameter.

I’m absolutely astonished when we find out at the end of the day that we’re not all that far out from the meteorite diameter value which the professionals have estimated for the Nevada crater. Okay, we’ve made lots of assumptions and approximations along the way, not the least of which was ignoring the explosion that accompanies real meteorite impacts. Maybe the errors we’ve made in our measurements have all cancelled themselves out, but I’m impressed nevertheless. I'd never have thought it possible…

< Previous


Mike performing impact tests
Scientists Diaries

All craters great and small - read the other team members' diaries as they attempt to measure the impact of impacts: