How stretched is Surtur’s orbit?

Eccentricity explained with one of Saturn’s most elongated orbits.

Published 2026-10-23

Eccentricity describes an orbit’s shape: close to 0 is circular, close to 1 very elongated. Saturn’s Norse moons all have eccentric orbits.^[2]

Surtur’s value

JPL’s mean eccentricity for Surtur is about 0.45.^[3] Wikipedia lists 0.451.^[1]

What it means

Surtur swings from about 12.6 million km to about 32.9 million km from Saturn — its far point is more than 2.5 times its near point.^[3]

Compare Phoebe

Phoebe, Saturn’s best-known distant moon, orbits at a mean of about 12.9 million km — close to Surtur’s nearest approach.^[3]

Numbered citations link to the sources list on the Surtur overview page.