Bauer & Westfall

This app lets you travel on board of the starship Enterprise and explore ... the practical consequences of special relativity. There are two sliders in this applet that you can use: the vertical slider controls the speed of the spaceship, and the horizontal slider controls the distance traveled to the faraway star system. Click on the START button, and off you go. Displayed will be the starship - properly length contracted (as viewed from Earth's reference frame) - on it's trip, as well as the time t' on board of the Enterprise and the time t on Earth.