Elizabeth Essex-Cohen (nee Essex)
This profile was written from publicly available information
Elizabeth Annette Essex-Cohen was one of the first women in Australia to complete a Doctor of Philosophy (PhD) in physics. She gained international recognition as a first class ionosphere physicist for her pioneering work on the global positioning satellite (GPS) system. Elizabeth developed her own research program into the study of the ionosphere and played a pivotal role in the creation of FedSat- Australia’s first launched satellite in 30 years which continues to operate today.
She was appointed a senior lecturer in Space Physics at La Trobe University in 1968. While she taught undergraduates and research students, she continued to explore new ways of observing the ionosphere using the tools of the space age.
During her time at La Trobe, Elizabeth helped form research links with the Australian Antarctic Division and pioneered the University’s partnership with the Co-operative Research Centre for Satellite Systems. This resulted in the construction and launch of FedSat in 2002, a satellite which has opened up a new means of studying the outer regions of Earth’s atmosphere, as far out at 22,000km. Elizabeth was the project leader for the satellite’s space-based GPS observations and experiments.
After the FedSat project, she continued her GPS research and worked at the US Air Force Geophysical Research Laboratory where she produced a study of the bending of radio waves from orbiting satellites. This knowledge was essential in the development of Satellite Navigation (SatNav), the earliest form of the GPS navigational system.
This then led to the formation of an international group of scientists known as the “Beacon Satellite Group”. Elizabeth was considered a valued member and helped to plan international conferences and exchanged ideas and results to expand on the research into the field of space physics.
As the fourth woman to gain a PhD in physics in Australia, Elizabeth was the only one to be both a lifelong researcher and lead a full life as a wife and mother of four children.
Elizabeth remained a long-term academic at La Trobe University until her death in 2004 and has inspired many students who have embarked on significant careers of their own.
In a tribute, Heath McCreadie, who gained a PhD at La Trobe, said:
“Elizabeth was a role model for me. She was quiet and gentle, yet very determined. She helped me to become strong and stick by decisions. She showed me that being a scientist didn’t mean I had to stop being a woman. Her example and leadership helped to forge my career. It is from her that I got my strength to continue to follow the path of science in the face of much adversity.”