1. The problem statement, all variables and given/known data This is a relativity problem: A tree and a pole are 3000 m apart. Each is hit by a bolt of lightning. Mark, who is standing at rest midway between the two, sees the two lightning bolts at the same instant of time. Nancy is flying her rocket at v = 0.5c in the direction from the tree toward the pole. The lightning hits the tree just as she passes by it. Define event 1 to be “lightning strikes tree” and event 2 to be “lightning strikes pole.” For Nancy, does event 1 occur before, after, or at the same time as event 2? The actual answer: After 2. Relevant equations 1) The speed of light is constant in all reference frames 3. The attempt at a solution I really can't figure this one out. The classic example, in which a train rider sees two lighting bolts, differs in that the rider is at the middle of the train. Thus, the example prepares us for a seemingly impossible result. Here, Nancy literally passes the train as it begins to move right. Doesn't she see event 1 first then?