Merri Sue Carter is an astronomer at the U.S. Naval Observatory, Flagstaff Station. She received an M.S. degree from the University of Maryland. Her primary work is studying polar motion and variations in the rotation of Earth, using VLBI and Global Positioning System (GPS) observations collected at stations around the world. This father-and-daughter team has written two books and several refereed papers on astronomy’s beginnings in the United States and on the discoveries that gave America its earliest scientific credibility.