Question

4. Suppose you synchronize your coordinate system with a traveler as he passes you at a steady speed of 0.98c. 1.4 years later, a black hole appears (magically) 7.9 light years away from you directly in the travelers path. Where and when did the black hole appear in the travelers reference frame? If you sent a message (on a radio wave) to the traveler to warn him (he’s pretty oblivious), will he receive the message before colliding with the black hole?

Answer 1