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This paper presents a study of star tracker attitude estimation algorithms and implementation on an indoor ground-based Three Axis Spacecraft Simulator (TASS). Angle, Planar Triangle, and Spherical Triangle algorithms are studied for star pattern recognition. Least squares, QUEST and TRIAD algorithms are studied for attitude determination. A star field image is suspended above TASS. The indoor laboratory environment restricts the placement of the star field to be in close proximity to TASS. This restriction adds some additional complication to the standard attitude determination problem. An iterative solution handles this complication. Experimental verification is also performed for the proposed iterative solution. I