Thesis Defense by Christopher Church on April 29th
Space Studies Master’s student, Christopher Church, will defend his thesis as follows. Please show your support by attending.
When: Tuesday, April 29, 2014 at 3:00 p.m. (Central) (note time change)
Where: Ryan Hall, Room 111 (note room change)
Title: A FEASIBILITY STUDY ON THE IMPLEMENTATION OF SATELLITE-TO-SATELLITE TRACKING AROUND A SMALL NEAR-EARTH OBJECT
About the Topic: There are currently more than 10,000 known Near-earth objects (NEO). The majority of these objects are less than 1 km in diameter. Despite the number of NEOs, little is known about most of them. Characterizing these objects is a crucial component in developing a thorough understanding of solar system evolution, human exploration, exploitation of asteroid resources, and threat mitigation. Of particular interest is characterizing the internal structure of NEOs. While ground-based methods exist for characterizing the internal structure of NEOs, the information that can be gleaned from such studies is limited and often accompanied by large error. An alternative is to use in situ studies to examine an NEO’s shape and gravity field. These can in turn be used to assess its internal structure.
This work investigated the use of satellite-to-satellite tracking (SST) to map the gravity field of a small NEO on the order of 500 m or less. An analysis of the mission requirements of two previously flown SST missions, GRACE and GRAIL was conducted. A simulation was also developed to investigate the dynamics of SST in the vicinity of a small NEO. The simulation was then used to simulate range and range-rate data in the strongly perturbed environment of the small NEO. These data were used in conjunction with the analysis of the GRACE and GRAIL missions to establish a range of orbital parameters required for executing low-low SST mission around a small NEO and to establish the time available for data collection between orbital correction maneuvers.
BIO: I graduated from James Madison University with a Bachelor of Science in Physics. After graduation I worked briefly in the aircraft instrumentation industry before accepting an engineering position at a small test and measurement company. This position afforded me the opportunity to work with many aerospace companies configuring and designing test systems for a variety of applications. After several years, my exposure to the aerospace industry and my interest in space led me to the Space Studies program at UND. I began the program in 2010 and started working on Near Earth Object mission design shortly after. My interest in investigating NEO internal structure grew out of early participation in this mission design work, which was headed by Dr. Fevig.
1) A live webcast which includes PowerPoint slides will be available here. Please note: this option is currently not operational on portable devices/tablets.
2) A simple live webcast is also available here