Now although sunlight indeed travels along straight lines, the projections of these lines onto the spherical sky are greatcircles.
虽然阳光呈直线照射，但光线在球型天空的投影却是巨大的圆形。
2
So she changed the eldest into an eagle, which was forced to dwell in the Rocky Mountains, and was often seen flying in greatcircles in the sky.
于是她把老大变成了苍鹰，只能生活在石山上，人们时常看见它在空中盘旋翱翔。
3
Dr Penrose, though, predicts another form of irregularity—greatcircles in the sky where the microwave background is slightly more uniform than it should be.