Dr. Margaret Rhea Seddon, otherwise known as Rhea, spent 19 years at NASA playing numerous rolls along with meeting her husband, a fellow astronaut. She receive her Bachelor’s degree in physiology from the University of California and following, a doctorate of medicine degree from the University of Tennessee. He primary focus after medical school was to focus on her general surgery residency but plans soon changed when she was accepted into the NASA Johnson Space Center training program for the space shuttle program in 1978. She is most famously known for performing the first echocardiogram in space. During her 722 hours in space, Rhea flew as both a mission specialist and a payload commander while performing numerous cardiovascular experiments during her flights.