Operationally Responsive Spacecraft Using Electric Propulsion

A desirable space asset is responsive and flexible to mission requirements, low-cost, and easy to acquire. Highly-efficient electric thrusters have been considered a viable technology to provide these characteristics; however, it has been plagued by limitations and challenges such that operational implementation has been severely limited. The technology is constantly improving, but even with current electric propulsion, a spacecraft is capable of maneuvering consistently and repeatedly in low-Earth orbit to provide a responsive and flexible system. This research develops the necessary algorithm and tools to demonstrate that EP systems can maneuver significantly in a timely fashion to overfly any target within the satellite’s coverage area. An in-depth analysis of a reconnaissance mission reveals the potential the proposed spacecraft holds in today’s competitive, congested, and contested environment. Using Space Mission Analysis and Design concepts along with the developed algorithm, an observation mission is designed for three conventional methods and compared to the proposed responsive system. Analysis strongly supports that such a spacecraft is capable of reliable target overflight at the same cost as non-maneuvering ones, while it is three times as responsive in terms of time-to-overflight by sacrificing one third of its mission life. An electric versus a chemical system can maneuver 5.3 times more. Its responsiveness and mission life are slightly inferior to that of a Walker constellation, but cuts total system cost by almost 70%

Invoice from Thomas Meadows & Co. to Ogden Goelet

https://digitalcommons.salve.edu/goelet-personal-expenses/1119/thumbnail.jp

A Taskable Space Vehicle: Realizing Cost Savings by Combining Orbital and Suborbital Flight

The use of space gives the United States distinct advantages in any battlefield environment, but the high cost of space operations increasingly jeopardizes those advantages. Although the United States pioneered much of the current space technology, declining budgets for space research, development, and operations leave our legacy systems vulnerable to adversaries around the world. Other nations formerly incapable of space exploitation are quickly learning to counter US space technologies at surprisingly low costs. In order to reduce the expense of deploying and maintaining a robust space capability, the Department of Defense (DOD) must change the status quo in space operations or risk losing its dominance

Receipt from Thomas Goode & Co. to Mrs. Robert Goelet

https://digitalcommons.salve.edu/goelet-personal-expenses/1325/thumbnail.jp

Attack on Fort Wagner

The black and white steel engraving features a battle scene from the Battle of Morris Island, which took place at Fort Wagner, South Carolina in 1863. The image depicts men fighting on either side of a fallen barrier wall. An American flag, held by a soldier, is featured at the center of the image. The engraving is printed on off-white paper.https://scholarsjunction.msstate.edu/fvw-prints/1068/thumbnail.jp

Battle of Chicamaug Lt. Van Pelt Defending His Battery

The black and white steel engraving features a scene from the Battle of Chickamauga. Lt. Van Pelt is shown standing by a cannon across from a line of Confederate soldiers. Union soldiers cover him from behind. The image is printed on off-white paper with black ink and appears to have be torn from a bound volume.https://scholarsjunction.msstate.edu/fvw-prints/1072/thumbnail.jp

Battle of Lookout Mountain

The black and white engraving depicts a scene from the Battle of Lookout Mountain. Union soldiers are shown climbing rough terrain to face the Confederate army. The image is printed on off-white paper with black ink and appears to have been removed from a bound volume.https://scholarsjunction.msstate.edu/fvw-prints/1051/thumbnail.jp

Shut Tight Dose Winkin\u27 Blinkin\u27 Eyes / words by Thomas Curtis Clark

Key of Eb. Cover: A southern lullaby, a drawing of trees; Publisher: The Thompson Music Co. (Chicago)https://egrove.olemiss.edu/sharris_b/1054/thumbnail.jp