The speaker imagines standing at the far frontier of the universe, where time stops behaving the way we know it. Instead of running in a line, it loops back on itself. Every event happens at once, yet each one sits sealed in its own "time capsule," cut off from the rest. The poem openly contradicts itself here: events are separate and simultaneous, never repeated and yet all the same. These paradoxes are the point, since the speaker is trying to describe something ordinary logic can't hold.
The last stanza turns to a biological image. Time becomes an "ambi-morphous amoeba" that pushes its body into a butterfly's flight, and the amoeba's mouth becomes the wingtip's drive. One shape melts into another without a break, a picture of change and continuity at once.
The mood is calm, strange, and awed. The speaker sounds less frightened than fascinated, as if puzzling over something vast and quietly beautiful.