Chapter32 Relativity The time between departure Farth 卫○ of earth and arrival of Neptune is the proper time Because the two events occur at the same point in space-on le spacecra ft △n=△y1-(v/c) L is the distance between two events as viewed by the spacecraft observers, then L=vAThe time between departure o f Ea r t h a n d a r r i v a l o f Neptune is the proper time, Because the two events occur at the same point in space-on the spacecraft. 2 0 t  t 1 (v / c) L is the distance between two events as viewed by the spacecraft observers, then 0 Lvt