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Chronos Spacecraft with Chiron Probe: Exploration of the Hydrosphere, Principle Satellites, Atmosphere, and Rings of Uranus

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Chronos Spacecraft with Chiron Probe: Exploration of the Hydrosphere, Principle Satellites, Atmosphere, and Rings of Uranus Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 9-2020 Chronos Spacecraft with Chiron Probe: Exploration of the Hydrosphere, Principle Satellites, Atmosphere, and Rings of Uranus Payton E. Pearson Follow this and additional works at: https://scholar.afit.edu/etd Part of the Space Vehicles Commons, and the The Sun and the Solar System Commons Recommended Citation Pearson, Payton E., "Chronos Spacecraft with Chiron Probe: Exploration of the Hydrosphere, Principle Satellites, Atmosphere, and Rings of Uranus" (2020). Theses and Dissertations. 4333. https://scholar.afit.edu/etd/4333 This Thesis is brought to you for free and open access by the Student Graduate Works at AFIT Scholar. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of AFIT Scholar. For more information, please contact [email protected]. CHRONOS SPACECRAFT WITH CHIRON PROBE: EXPLORATION OF THE HYDROSPHERE, PRINCIPLE SATELLITES, ATMOSPHERE, AND RINGS OF URANUS THESIS Payton E. Pearson, Captain, USAF AFIT-ENG-MS-20-S-015 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED The views expressed in this thesis are those of the author and do not reflect the official policy or position of the U.S. Air Force, the Department of Defense, or the U.S. Government. The views expressed in this thesis are those of the author and do not reflect the official policy or position of the U.S. Air Force, Department of Defense, or the U.S. Government. This material is declared a work of the U.S. Government and is not subject to copyright protection in the U.S.. AFIT-ENG-MS-20-S-015 CHRONOS SPACECRAFT WITH CHIRON PROBE: EXPLORATION OF THE HYDROSPHERE, PRINCIPLE SATELLITES, ATMOSPHERE, AND RINGS OF URANUS THESIS Presented to the Faculty Department of Aeronautics and Astronautics Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In Partial Fulfillment of the Requirements for the Degree of Master of Science in Electrical Engineering Payton E. Pearson, BS Captain, USAF September 2020 APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENG-MS-20-S-015 CHRONOS SPACECRAFT WITH CHIRON PROBE: EXPLORATION OF THE HYDROSPHERE, PRINCIPLE SATELLITES, ATMOSPHERE, AND RINGS OF URANUS Payton E. Pearson, BS Captain, USAF Approved: Dr. Carl Hartsfield Dr. Carl Hartsfield Chair Dr. Robert Mills Member Maj Robert Bettinger, PhD Member Maj Joshuah Hess, PhD Member AFIT-ENG-MS-20-S-015 Abstract A design reference mission using improved technologies has been developed for exploration of the outer reaches of our Solar System, specifically Uranus and its system of satellites. This mission will utilize theoretical technologies mostly without regard to their current technological readiness level (TRL), though most systems have a TRL of at least 5. The primary innovations explored in this thesis are the new launch systems that provide far greater payload capacity potentially sent to anywhere in the Solar System, new Stirling- engine radioisotope thermoelectric generators (SRTGs), vastly improved data storage technologies, optimized satellite antenna relay of data using much higher transfer frequencies and wider arrays, and much more precise gyroscopes that allow for more powerful communications, only to name a few improvements. The final result is a payload capacity of greater than 3,000 kg that can be sent to Uranus, data transfer rates of upwards of 10 Mbps that the Earth will receive from the probe and its satellite system, 6 kW (4.5 kW at time of reaching Uranus) of power generated by all SRTGs onboard the spacecraft, all accomplished in a single launch that will take approximately 15 years to reach the water world. 1 Acknowledgments I would like to express my sincere appreciation to my faculty advisor, Dr. Carl Hartsfield, for his guidance and support throughout the course of this thesis effort. The insight and experience he provided was certainly appreciated. Captain Payton E. Pearson 2 Table of Contents Page Abstract ................................................................................................................................1 Table of Contents .................................................................................................................3 List of Figures ......................................................................................................................6 List of Tables .......................................................................................................................9 CHRONOS SPACECRAFT WITH CHIRON PROBE: EXPLORATION OF THE HYDROSPHERE, PRINCIPLE SATELLITES, ATMOSPHERE, AND RINGS OF URANUS ...........................................................................................................................10 I. Introduction ...................................................................................................................10 1.1 Uranus and the Purpose of Space Exploration .....................................................10 1.2 Thesis Objectives..................................................................................................13 1.3 Problem Statement................................................................................................18 II. Literature Review ..........................................................................................................20 2.1 Chapter Overview .................................................................................................20 2.2.1 Mariner II through IX ........................................................................................21 2.2.2 Viking I and II ...................................................................................................27 2.2.3 Voyager I, II ......................................................................................................31 2.2.4 Galileo ...............................................................................................................33 2.2.6 Mars Pathfinder .................................................................................................40 2.2.7 Cassini-Huygens ................................................................................................41 2.2.8 Uranus Pathfinder ..............................................................................................49 2.3 Patched Conics and Hohmann Transfers ..............................................................50 2.4 Uranus...................................................................................................................51 III. Methodology ...............................................................................................................60 3 3.1 Chapter Overview .................................................................................................60 3.2 Stirling RTGs........................................................................................................62 3.3 Communications and Data Handling....................................................................65 3.4 Traveling-Wave Guide Amplifier (TWTA) Calculations: ...................................82 3.5 Constellation Design ............................................................................................83 3.6 Inclination Changes ..............................................................................................88 3.7 Launch Window Design .......................................................................................90 3.8 Tidal Force Effects .............................................................................................101 3.9 Probe Design ......................................................................................................106 3.10.1 Doppler and Collision Broadening Science ..................................................110 3.10.2 Collision Broadening Calculations Methodology .........................................111 3.10.3 Doppler and Overall Broadening Calculations..............................................116 3.10.4 Doppler and Collision Broadening Modelling Through Filters ....................117 3.11 Falcon 9 Heavy Launch Vehicle ......................................................................119 3.12 Orbital Dynamics..............................................................................................121 3.13 Launch ∆V Estimations ....................................................................................129 3.14 Atmospheric Insertion Dynamics .....................................................................132 IV. Analysis and Results .................................................................................................137 4.1 Chapter Overview ...............................................................................................137 4.2 Results of Doppler and Collision Broadening Models .......................................137 4.3 Settled Upon Frequency Range ..........................................................................138 4.4 Settled Upon General Probe Design ...................................................................141 4.5 Settled Upon Launch Specifications ..................................................................145 4 4.6 Settled Upon SRTG Dynamics ...........................................................................147
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