 However, they do not attempt to reach the sole remaining rocket ship due to the futility of attempting to reach it in one hour, which is the longest length of time between day and night (both deadly).Sim is then moved by the memory of his ancestors to find and meet with scientists who make halting progress towards the goal of lengthening the world's decreased life span.Sim, motivated by his dwindling days, makes it his goal to extend his life and reach the distant rocket, despite the protests of his sister and other cave-dwellers.