Jessie Christiansen is an Australian astrophysicist who serves as the Chief Scientist of the NASA Exoplanet Science Institute at the California Institute of Technology (Caltech). She completed a Bachelor of Science (Advanced Studies) in physics and mathematics at Griffith University in 2002, followed by a BSc first class honours in Astronomy at the Australian National University. She earned her PhD from the University of New South Wales in 2007.