You are the first astronaut aboard a ship to travel to Alpha Centauri. Coincidentally, a scientist working on an outer space station post is one of your former classmate. Your ship, with your former classmate onboard, leaves the space station traveling at constant velocity v on its way to Alpha Centauri, a distance d away from the space station. You and your former classmate devise a clever plan to celebrate your arrival at Alpha Centauri exactly when scientists at the space station observe, through their telescope, your ship arriving at Alpha Centauri. To do this, you have to calculate the time according to the clock on the spaceship and the time at according to the clock at the space station.