1. The problem statement, all variables and given/known data Suppose our sun is about to explode. In an effort to escape, we depart in a spaceship at v = 0.8c and head toward the start Tau Ceti, 12 light years away. When we reach the midpoint of our journey from the Earth, we see our Sun explode and, unfortunately, at the same instant we see Tau Ceti explode as well. (a) In the spaceship's frame of reference, should we conclude that the two explosions occurred simultaneously? If not which occurred first? (b) In a frame of reference in which the Sun and Tau Ceti are at rest, did they explode simultaneously? If not, which exploded first? 2. Relevant equations Lorentz transforms, velocity transforms 1 lightyear = the distance light travels in one year = c*(1 year) 3. The attempt at a solution I'm really confused about how to approach this problem. Any hints? Thanks.