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.
Born: October 17, 1956. Decatur, Alabama. African American physician and astronaut. Mae Jemison, a doctor, was the first African American woman to be selected for the National Aeronautic and Space Administration's (NASA's) astronaut training program and was the first African American woman to travel in space.