George Greenstein

Astrophysicist / Educator / Writer

Sidney Dillon Professor of Astronomy Emeritus at Amherst College

Homepage -- Contact George

George Greenstein Blog

A Trip to Alpha Centauri

Conventional rocketry cannot do the trick. We need new technology

Fun Physics Puzzles

They’ve got me stumped -- how about you?

A tip for teachers

The incessant talker can be a problem