A spacecraft is moving at speed 0.61c relative to two star systems—star system A and star system B— that are always the same distance apart with respect to each other. Observers aboard the spacecraft measure the time taken to travel from start system A to star system B as 23.22 years. What is the distance between the two star systems, in light-years, as measured by an observer that is bound to star system B.

A spacecraft is moving at speed 0.61c relative to two star systems—star system A and star system B— that are always the same distance apart with respect to each other. Observers aboard the spacecraft measure the time taken to travel from start system A to star system B as 23.22 years. What is the distance between the two star systems, in light-years, as measured by an observer that is bound to star system B.