Abstract: Spacecraft propulsion systems and methods featuring a first storage tank containing a metallic propellant and a second storage tank containing a non-metallic propellant are provided. A selected one of the metallic propellant and the non-metallic propellant is supplied to an electric propulsion thruster, depending on an operational mode of the spacecraft. The metallic propellant is stored at a relatively high density, while the non-metallic propellant is stored at a lower density than the metallic propellant. Moreover, the non-metallic propellant is preferably utilized to produce thrust through the electric propulsion thruster during operational maneuvers, while the metallic propellant is reserved for producing thrust through the electric propulsion thruster during end-of-life, such as deorbiting, maneuvers.

Abstract: A method and an apparatus for designing generalized tables. The method and the apparatus are described by a collection of processes for performing operations such as creating a generalized table, deleting a generalized table, drawing a rule, stretching or shrinking a rule, shifting a set of rules, deleting a rule, aligning a rule, unaligning a rule, combining cells, dividing a cell, creating a region, and deleting a region.