Picks

The Mosquito Killer

What do you think of when someone mentions DDT (dichloro-diphenyl-trichlorethane)? Chances are that your mind immediately goes to the damage the use of this chemical has done to bird populations, Rachel Carson's "Silent Spring", and the effort to ban or control its use.

The Shaken-Soda Syndrome

Try this! Take two identical cans of soda (or some other beverage). Roll then down a slight incline to confirm that they roll at about the same speed. What do you think will happen if you shake up one can and roll them again? Make a prediction. Then try it. Have your students do it. Develop hypotheses and test them. This is a terrific experiment that anyone can do.

Impact Event at the Permian-Triassic Boundary: Evidence from Extraterrestrial Noble Gases in Fullerenes

It has been twenty years since Luis Alvarez suggested that the dinosaurs were extinguished by a meteor impact that killed much of the life on earth. His evidence was in a thin layer of iridium-rich soil that corresponded with the extinction, and the fact that iridium is much more abundant in some meteors than it is on earth.