An alien spaceship traveling at 0.500c toward the Earth launches a landing craft. The landing craft travels in the same direction with a speed of 0.780c relative to the mother ship (as measured by aliens on the mother ship). As measured on the Earth, the spaceship is 0.250 ly from the Earth when the landing craft is launched. What travel time is required for the landing craft to reach the Earth as measured by Earth-based observers? What travel time is required for the landing craft to reach the Earth as measured by those on the landing craft?