An element is a chemical substance made up of a particular kind of atom and hence cannot be broken down or transformed by a chemical reaction into a different element, though it can be transmuted into another element through a nuclear reaction.
Almost 40 years separate Shirley Ann Jackson's achievement, as the first African-American woman to earn a Ph.D. in theoretical high energy physics at Massachusetts Institute of Technology, and Jedidah Isler, the first African-American woman to receive a Ph.D. in Astrophysics from Yale.
Burby, Liza N. Mae Jemison: The First African American Woman Astronaut, The Rosen Publishing Group, 1997 â ISBN 0-8239-5027-1; Canizares, Susan. Voyage of Mae Jemison, Sagebrush Education Resources, 1999 â ISBN 0-613-22577-5; Ceaser, Ebraska D. Mae C. Jemison: 1st Black Female Astronaut, New Day Press, 1992. Polette, Nancy.