Knight in Stainless Armor NASA's highly ambitious Mars Sample Return (MSR) mission is on thin ice. An independent review board balked last year at the Mars Sample Return mission's "unrealistic" budget, highly complex mission design, and glaring management failures. Earlier this year, budget cuts forced the agency's Jet Propulsion Lab to let go of a whopping 530 employees, with NASA leaders racing to keep the MSR mission from imploding completely…