Thesis Defense by John Shepard on April 27th

Space Studies M.S. candidate, John Shepard, will defend his thesis as follows.  All Space Studies students and faculty are encouraged to show your support by attending.

When:  Monday, April 27th at 1:00 pm (Central DST)

Where:  online only – see details below

Title:  A Preliminary Study of LEO to GEO Transfers for Inclination Changes Using Libration Point Orbits

About the topic: Inclination changes in space are difficult as such maneuvers require large amounts of fuel in an environment where fuel is a limited resource. One unique method to address the issue of fuel usage is to take advantage of the surrounding gravitational forces around Earth. The gravitational force of the Sun – Earth/Moon system are used in the form of the circular restricted three-body problem. The model developed is used to create a maneuver that is more efficient than traditional transfer methods like a Hohmann transfer. The trajectory design takes advantage of unique properties of the gravitational model that allows for decrease fuel usage. The properties used are known as invariant manifolds and libration point orbits. With the maneuver presented different potential uses are explored along with costs and the hazards of the space environment.

Advisor:  Dr. Ronald Fevig

About the Presenter: John is a Senior Software Engineer at Lockheed Martin Rotary Mission Systems where he develops software for satellite systems. Additionally, He also serves in the Pennsylvania Air National Guard as a Cyber Systems Operations Specialist where he provides communication support for remotely piloted aircraft missions. In May, John will be starting a new career path with Lockheed Martin Space as a Senior Guidance Navigation and Control Engineer where he will be designing spacecraft trajectories through modeling and simulation. In his personal life he is happily married with five children.

Join us online via one of two formats:

A simple live webcast will be available here.

Via Zoom video conferencing.  Questions for the speaker may be posted at this site during the presentation.

meeting number: 327-372-990


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