Question

1) Consider a perfectly spherical alien spaceship with a diameter of 10 meters. It moves past you (while you are standing on Earth) with a speed of 0.5c. You have the presence of mind to take a (perfect) photo of the spaceship when it is directly in front of you. a) What shape does the spacecraft in the photo have? What are its dimensions? b) You see two lightning bolts hit each side of the spacecraft simultaneously (as captured in your photo). Later on, you are talking with the alien as its ship is racing away from Earth. The alien is convinced that the lightning hit the front of his spaceship first. Explain this (or perish, Earthling!) c) You travel on the alien's ship for what appears to you to be 6 years (at a constant speed of 0.8c). How many years have passed on Earth while you were gone?