It means round and thin which is what a circle is
The literal meaning -the poet has to travel miles before he reaches home and sleeps.
Metaphorical meaning of sleep -sleep is a metaphor for death. The poet has to fulfill a lot of responsibilities before he dies.
The author most likely chose to call this story “The Cold Equations” because he believes that space is a freezing wasteland wants to indicate that the EDS is cold needs to communicate that math is boring tries to foreshadow that numbers are heartless
Include a picture of the texts so I can a answer.
