In this clip, Dr. Worth Seagondollar describes the after-effects of the 1st man-made nuclear explosion on the New Mexico desert floor.
Note: This is a large file (45MB), and may take several minutes to load depending on your connection speed. You can also save the file to your desktop by right-clicking the link and selecting "save target as."
http://www.spsnational.org/programs/internships/2007/seagondollar2.mpg