Since it opened in 1824, The Franklin Institute has been giving annual awards for achievement in science and technology. This year's awards ceremony is this evening, when the Benjamin Franklin Medal in Earth Science will be awarded to Dr. Rob Van der Voo, Professor of Geology at the University of Michigan.

Dr. Van der Voo's research spans hundreds of millions of years of earth history. You may know that the earth's crust is broken into a few dozen pieces called plates which drift very slowly, maybe an inch or so a year. As a result, the continents have not always been where they are today. You may also know that the earth has a magnetic field - that's why compasses work. But that magnetic field has also changed over long periods of time. Dr. Van der Voo figured out how to use the variations in earth's magnetic field to track the movement of the plates, and in doing so allowed us to estimate where the continents and oceans have been during the past billion years or so of earth history. He has, you could say, helped shape a new scientific discipline that might be called "paleomagnetism" or "paleogeography," where "paleo" means "ancient."

By the way, the awards ceremony will be webcast tonight, starting at 7 o'clock. Just point your browser to the Franklin Institute web site at

http://www.fi.edu/webcast

to tune in.