1. If astronauts could travel at v = 0.950c, we on Earth would say it takes 4.42 years to reach Alpha Centauri, which is 4.20 light-years away. The astronauts disagree. a. How much time do the astronauts measure has passed? b. What is the distance to Alpha Centauri as measured by the astronauts? c. Before the spaceship leaves Earth, a person on Earth measures the spaceship to be 75.0 m. What is the ship's proper length?