sentences:  in Astronomy at Vanderbilt University, he received a one-year internship at the Strasenburgh Planetarium in Rochester, New York.He has held positions at the Smithsonian Institution's National Air and Space Museum in Washington, D.C. from 1975-1978, the Flandrau Planetarium of the University of Arizona in Tucson from 1978-1986, and the Reuben H. Fleet Science Center in San Diego, California from 1987-2001.Mammana has authored six astronomy books for adults and children, as well as hundreds of magazine, encyclopedia and web articles.