White LRSI (low-temperature reusable surface insulation) tiles were an integral component of the Space Shuttle's thermal protection system. This system shielded the vehicle from the destructively searing heat of re-entry into the earth's atmosphere and also provided passive thermal control in orbit. White tiles covered selected areas on the sides and upper surfaces of the vehicle where temperatures remain below 1,200° F (650° C). Originally about 7,000 LRSI tiles protected portions of the vertical tail, OMS pods, upper wing, and the forward, mid and aft fuselages. However, many tiles were replaced with quilted insulation blankets because they were lighter weight, more durable, and easier to produce and install than tiles. This tile was removed after being damaged on the first flight of Columbia in 1981. NASA transferred a number of such tiles to the Museum after the STS-1 mission.