URANUS SYSTEM / SATELLITE DOSSIER

Perdita

Perdita is a tiny dark moon of Uranus, identified in archived Voyager images and later confirmed with the Hubble Space Telescope.

Moon view ↗

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Artist’s impression of Perdita

Perdita is a tiny dark moon of Uranus, identified in archived Voyager images and later confirmed with the Hubble Space Telescope.

Environment ↗

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DIAMETER / EARTH0.0024×
EARTHPERDITA
ATMOSPHERE
No substantial atmosphere detectedEffectively airless
SURFACE TEMPERATURE
Cold exposed surface
SURFACE PRESSURE
Effectively airless
HABITABILITYNo life detected
UNPROTECTED HUMANSNot survivable

Interior ↗

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Perdita interiorPerdita's internal structure is unresolved.Unresolved

Moon system ↗

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Uranus moon orbitsSelected moons, ordered outward. Orbit sizes and positions are schematic; relative periods are preserved.URANUSCORDELIAOPHELIABIANCACRESSIDADESDEMONAJULIETPORTIAROSALINDCUPIDBELINDAPERDITAPUCKMABMIRANDAARIELUMBRIELTITANIAOBERON

Landscape ↗

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A speculative ground-level view on Perdita. The fragments, depressions and distant relief are artistic reconstructions.
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Rotation ↗

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Perdita rotationThe rotation period is unresolved. Static portrait, not an orientation prediction.PERIOD UNCERTAINNO UNIQUE PERIOD ADOPTED

Gravity ↗

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GRAVITY UNKNOWNMASS UNCERTAIN

Orbit ↗

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Perdita orbitElliptical orbit viewed along the orbital axis, relative to Uranus. Motion is accelerated, not a live position. Distances are center to center.URANUSPERDITA≈ 76,418 km
Sources ↗
PERDITA

Instrument detail

THE SKY FROM PERDITA

Uranus, in perspective.

SHARED ANGULAR SCALE
Uranus compared with Luna in Earth's skyAt semimajor-axis distance, Uranus spans approximately 39.09 degrees, 75.47 times the apparent diameter of Luna at its mean distance from Earth. Both disks share one angular scale.URANUSOUR MOON≈ 0.52°
Idealized size study · full disks · decorative lighting · rings excluded
ANGULAR DIAMETER
39.09°
OUR MOON'S APPARENT DIAMETER
75.47 ×
CENTER-TO-CENTER DISTANCE
76,418 km

The viewpoint is on Perdita’s nominal spherical surface, directly facing Uranus. The reference is Luna seen from Earth’s center at its mean distance. The reference distance is the orbit’s semimajor axis. Rounded body diameters and orbital elements set the disk sizes; terrain, phases, rings and the actual sky position are not modeled.

Explore Uranus ↗
Perdita orbitElliptical orbit viewed along the orbital axis, relative to Uranus. Motion is accelerated, not a live position. Distances are center to center.URANUSPERDITA≈ 76,418 km
ONE ORBIT0.6382 Earth days around Uranus
Closest to Uranus
76,036 km
Farthest from Uranus
76,800 km

Perdita circles Uranus. Distances are measured between the centers of the two bodies.

This URA184 mean-element path omits inclination, precession, ring dynamics and perturbations. It is not a live position prediction.

Perdita rotationThe rotation period is unresolved. Static portrait, not an orientation prediction.PERIOD UNCERTAINNO UNIQUE PERIOD ADOPTED
ROTATION STATEUncertain

Rotation remains uncertain

The cited overview gives no measured spin period. This static portrait assumes no fixed rate or orientation; uncertainty alone does not imply chaotic tumbling.

Satellite atlasMoons
Uranus moon orbitsSelected moons, ordered outward. Orbit sizes and positions are schematic; relative periods are preserved.URANUSCORDELIAOPHELIABIANCACRESSIDADESDEMONAJULIETPORTIAROSALINDCUPIDBELINDAPERDITAPUCKMABMIRANDAARIELUMBRIELTITANIAOBERON
FEATURED MOONS18
  1. 01Cordelia ↗0.3347 days
  2. 02Ophelia ↗0.3764 days
  3. 03Bianca ↗0.4347 days
  4. 04Cressida ↗0.4639 days
  5. 05Desdemona ↗0.4736 days
  6. 06Juliet ↗0.4931 days
  7. 07Portia ↗0.5132 days
  8. 08Rosalind ↗0.5583 days
  9. 09Cupid ↗0.6125 days
  10. 10Belinda ↗0.6236 days
  11. 11Perdita0.6382 days
  12. 12Puck ↗0.761833 days
  13. 13Mab ↗0.9229 days
  14. 14Miranda ↗1.41 days
  15. 15Ariel ↗2.5204 days
  16. 16Umbriel ↗4.1442 days
  17. 17Titania ↗8.7059 days
  18. 18Oberon ↗13.4632 days

Faint rings and a family of moons surround Uranus. Many of those moons take their names from characters in Shakespeare and Alexander Pope. One journey around the Sun lasts about 84 Earth years.

GRAVITY UNKNOWNMASS UNCERTAIN
SURFACE GRAVITYUnknown

Mass remains uncertain

No measured mass is adopted from the cited overview. A numerical gravity comparison would require additional assumptions and is omitted.

Perdita interiorPerdita's internal structure is unresolved.Unresolved

Beyond the surface

Perdita’s interior remains unresolved. The available observations do not establish distinct layers or a present-day ocean.

    Artist’s impression of Perdita

    A discovery waiting in the archive.

    Erich Karkoschka identified Perdita in 1999 while examining Voyager 2 images taken in 1986. The moon had been recorded during the flyby but overlooked in the original search.

    Hubble confirmed the missing companion.

    After follow-up searches failed, the initial recognition was withdrawn as premature. Hubble recovered an object at the predicted location in 2003, confirming Perdita’s existence.

    A tiny body still seen from afar.

    Perdita is estimated to be about 30 kilometers across and has a dark surface. Its shape, local geology and interior remain poorly constrained. The illustrations are speculative, not resolved surface maps.

    Between Belinda and Puck.

    The adopted mean elements give a 76,418-kilometer orbital scale and a period of 0.6382 Earth days. This approximate ellipse omits interactions with neighboring moons and does not predict their future encounters.

    DIAMETER / EARTH0.0024×
    EARTHPERDITA
    EARTH
    12,742 km
    PERDITA
    30 km
    Mean diameters · circles share one scale

    Approximately 30 km across, following NASA’s overview. This is a size estimate, not a detailed shape model.

    ATMOSPHERE
    No substantial atmosphere detectedEffectively airless

    Perdita is effectively airless. No substantial atmosphere is known.

    SURFACE TEMPERATURE
    Cold exposed surface
    SURFACE PRESSURE
    Effectively airless
    HABITABILITYNo life detected

    No life has been detected, and a habitable environment has not been established.

    UNPROTECTED HUMANSNot survivable

    The exposed surface requires oxygen, pressure protection and thermal control.

    Planet and landscape images are artistic interpretations.

    • NASA ↗
      • Classification and orbital data
      • Mass and gravity constraints
      • Rotation model and synchronous or independent spin
      • Rotation and internal structure constraints
      • Size, physical data and atmospheric constraints
      • Natural conditions and human survival
      • Discovery
      • Recovery
      • Scale
    • NASA ↗
      • Parent-body diameter for the angular sky comparison
    • NASA / JPL ↗
      • Mean orbital dimensions; distances from parent center
      • Orbit
    A speculative ground-level view on Perdita. The fragments, depressions and distant relief are artistic reconstructions.

    Across an imagined hollow

    A speculative ground-level view on Perdita. The fragments, depressions and distant relief are artistic reconstructions.

    An imagined landscape on Perdita. Neither local terrain nor illumination reproduces a spacecraft panorama.

    Along a low rise

    An imagined landscape on Perdita. Neither local terrain nor illumination reproduces a spacecraft panorama.

    A modest dark rounded stone partly buried in fine gray regolith. An artistic reconstruction of Perdita; local detail, lighting and viewpoint are imagined.

    Surface fragments in close view

    A modest dark rounded stone partly buried in fine gray regolith. An artistic reconstruction of Perdita; local detail, lighting and viewpoint are imagined.