Required: L. = ? Analysis: According to an observer on the International Space Station, the space vehicle is moving, therefore she will measured relative length, L . The rocket was contracted (this is the value we are given). To an astronaut on the space vehicle, the space vehicle will look stationary (not moving), so the astronaut will measure the proper length, L. (this is the value we are solving for). We need to use the equation for proper length. Solution: L=L (1 L = (25.0 m)- /(1 - (26 x 10'1/!) (3.00 x 10 0?) 1 = (25.0 m) (1 - 0. 751) L = (25.0 m) /0. 248 L = 12.45 m L. = 12 m (2 sig figs) Statement: -- The length of the space vehicle as measured by an astronaut on the space vehicle is 12 m