Uranus’ Small Moons

Uranus’ innermost ten moons are:

  • Cordelia,
  • Ophelia,
  • Bianca,
  • Cressida,
  • Desdemona,
  • Juliet,
  • Portia,
  • Rosalind,
  • Belinda and
  • Puck.

(For information on the newly discovered moons see S/1997 U 1.)


Cordelia

Uranus VI

Cordelia is the innermost of Uranus’ known satellites:

        orbit:    49,752 km from Uranus
        diameter: 26 km
        mass:     ?

Cordelia is a daughter of Lear in Shakespeare’s King Lear.

Discovered by Voyager 2 in 1986.

Cordelia appears to be the inner shepherding satellite for Uranus’s Epsilon ring.

Cordelia and Ophelia orbit inside the synchronous orbit radius.

More about Cordelia

Ophelia

Uranus VII

Ophelia is the second of Uranus’ known satellites:

        orbit:    53,764 km from Uranus
        diameter: 32 km
        mass:     ?

Ophelia is the daughter of Polonius in Shakespeare’s Hamlet.

Discovered by Voyager 2 in 1986.

Ophelia appears to be the outer shepherding satellite for Uranus’s Epsilon ring.

More about Ophelia

Bianca

Uranus VIII

Bianca is the third of Uranus’ known satellites:

        orbit:    59,165 km from Uranus
        diameter: 44 km
        mass:     ?

Bianca is the sister of Katherine in Shakespeare’s Taming of the Shrew.

Discovered by Voyager 2 in 1986.

More about Bianca

Cressida

Uranus IX

Cressida is the fourth of Uranus’ known satellites:

        orbit:    61,767 km from Uranus
        diameter: 66 km
        mass:     ?

Cressida is the daughter of Calchas in Shakespeare’s Troilus and Cressida.Discovered by Voyager 2 in 1986.

More about Cressida

Desdemona

Uranus X

Desdemona is the fifth of Uranus’ known satellites:

        orbit:    62,659 km from Uranus
        diameter: 58 km
        mass:     ?

Desdemona is the wife of Othello in Shakespeare’s Othello.

Discovered by Voyager 2 in 1986.

More about Desdemona

Juliet

Uranus XI

Juliet is the sixth of Uranus’ known satellites:

        orbit:    64,358 km from Uranus
        diameter: 84 km
        mass:     ?

Juliet is the tragic heroine in Shakespeare’s Romeo and Juliet.

Discovered by Voyager 2 in 1986.

More about Juliet

Portia

Uranus XII

Portia is the seventh of Uranus’ known satellites:

        orbit:    66,097 km from Uranus
        diameter: 110 km
        mass:     ?

Portia is a rich heiress in Shakespeare’s Merchant of Venice.

Discovered by Voyager 2 in 1986.

More about Portia

Rosalind

Uranus XIII

Rosalind is the eighth of Uranus’ known satellites:

        orbit:    69,927 km from Uranus
        diameter: 54 km
        mass:     ?

Rosalind is a daughter of the banished Duke in Shakespeare’s As You Like It.

Discovered by Voyager 2 in 1986.

More about Rosalind

Belinda

Uranus XIV

Belinda is the ninth of Uranus’ known satellites:

        orbit:    75,255 km from Uranus
        diameter: 68 km
        mass:     ?

Belinda is the heroine in Alexander Pope’s The Rape of the Lock.

Discovered by Voyager 2 in 1986.

More about Belinda

Puck

Uranus XV

Puck is the tenth of Uranus’ known satellites:

        orbit:    86,006 km from Uranus
        diameter: 154 km
        mass:     ?

Puck is a mischievous fairy in Shakespeare’s Midsummer-Night’s Dream.

Discovered by Voyager 2 in 1986.

Of the 10 new Uranian moons discovered by Voyager 2, only Puck was discovered soon enough that the observation schedule could be adjusted to get images.

Puck and the other small moons are very dark (albedo less than 0.1).

More about Puck


Open Issues

  • Cressida and Bianca are within the Roche limit; are they stable or will they be disrupted?
  • These small moons are all very dark; Uranus’ larger moons are much brighter. Why?
  • We know next to nothing about these moons. Even the basic orbital and size data are not very accurate.