Editing Natural satellite (section)

== Shape ==
{{see also|Satellite planet}}
<!--Linked from [[Template:Infobox planetary system]]-->
[[File:Masses of all moons.png|thumb|300px|The relative masses of the natural satellites of the [[Solar System]]. [[Mimas (moon)|Mimas]], [[Enceladus]], and [[Miranda (moon)|Miranda]] are too small to be visible at this scale. All the irregularly shaped natural satellites, even added together, would also be too small to be visible.]]

Neptune's moon [[Proteus (moon)|Proteus]] is the largest irregularly shaped natural satellite; the shapes of Eris' moon [[Dysnomia (moon)|Dysnomia]] and {{dp|Orcus}}' moon [[Vanth (moon)|Vanth]] are unknown. All other known natural satellites that are at least the size of Uranus's [[Miranda (moon)|Miranda]] have lapsed into rounded [[ellipsoid]]s under [[hydrostatic equilibrium]], i.e. are "round/rounded satellites" and are sometimes categorized as [[planetary-mass moon]]s. (Dysnomia's density is known to be high enough that it is probably a solid ellipsoid as well.) The larger natural satellites, being tidally locked, tend toward [[Oval|ovoid]] (egg-like) shapes: squat at their poles and with longer equatorial axes in the direction of their primaries (their planets) than in the direction of their motion. Saturn's moon [[Mimas (moon)|Mimas]], for example, has a major axis 9% greater than its polar axis and 5% greater than its other equatorial axis. [[Methone (moon)|Methone]], another of Saturn's moons, is only around 3&nbsp;km in diameter and [[:File:Methone PIA14633.jpg|visibly egg-shaped]]. The effect is smaller on the largest natural satellites, where their gravity is greater relative to the effects of tidal distortion, especially those that orbit less massive planets or, as in the case of the Moon, at greater distances.
{| class="wikitable" style="font-size: 0.9em;"
! rowspan="2" width=120 | Name
! rowspan="2" | Satellite of
! colspan="2" | Difference in axes
|-
! km
! {{longitem|% of [[mean diameter]]}}
|-
| [[Mimas (moon)|Mimas]] || [[Saturn]] || 33.4 {{smaller|(20.4{{\}}13.0)}} || 8.4 {{smaller|(5.1{{\}}3.3)}}
|-
| [[Enceladus]] || Saturn || 16.6 || 3.3
|-
| [[Miranda (moon)|Miranda]] || [[Uranus]] || 14.2 || 3.0
|-
| [[Tethys (moon)|Tethys]] || Saturn || 25.8 || 2.4
|-
| [[Io (moon)|Io]] || [[Jupiter]] || 29.4 || 0.8
|-
| [[Moon|Luna]] || [[Earth]] || 4.3 || 0.1
|}