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Abstract

In memory of late Professor I. M. Cohen [1937-2007, whose lifelong dedication to teaching and research has inspired, and continues to inspire Abstract. Fundamental temperature solutions in closed form of composite spherical bodies are given for mixed and time-dependent boundary conditions. Solid and hollow spherical bodies are included as further examples. The solution requires calculating the roots of certain transcendental equations. A method is developed to find the roots rapidly. As a practical application, the two-layer composite solution is used to determine the available fuel mass of an orbiting spacecraft.