• WHY WE EXPLORE
• PLANETARY NEWS
• SPACE TOPICS
  • Contests, Events, and Awards
  • Extrasolar Planets
  • How It Works
  • Near Earth Objects
  • Our Solar System
    • Asteroids and Comets
    • Compare the Planets
    • Earth
    • Jupiter
    • Mars
    • Mercury
    • Moon
    • Neptune
    • Pluto and Charon
    • Saturn
    • Trans-Neptunian Objects
    • Uranus
      • Facts and Pictures
      • Voyager Images
      • Uranus' Rings
      • Uranus' Moons
      • Miranda
      • Ariel
      • Umbriel
      • Titania
      • Oberon
      • Missions to Uranus
      • Links
    • Venus
  • Search for Life
  • Space Missions
• FOR KIDS

browse projects: Apophis Mission Design Competition Asteroid Impact Mapping System Catalog of Exoplanets Drive a Mars Rover Extrasolar Planets Transit Search International Lunar Decade LIFE Experiment: Phobos Mars Climate Sounder Team Website Messages from Earth Observing Earth Pioneer Anomaly Planetary Microphones S.O.S: Save Our Science! SETI Optical Telescope SETI Radio Searches SETI@home Shoemaker NEO Grants Solar Sailing Space Advocacy Space Information Stardust@home Target Earth Visions of Mars

browse space topics: 2001 Mars Odyssey Asteroids and Comets Cassini-Huygens Chandra X-Ray Observatory Chandrayaan-1 Chang'e 1 Compare the Planets Dawn Deep Impact Earth Extrasolar Planets Genesis Hayabusa (MUSES-C) Hubble Space Telescope Jupiter Kaguya (SELENE) Lunar Reconnaissance Orbiter (LRO) Mars Mars Exploration Rovers Mars Express Mars Global Surveyor Mars Reconnaissance Orbiter Mercury MESSENGER Moon Near Earth Objects Neptune New Horizons New Horizons Digital Time Capsule Past Missions Phoenix Planetary Analogs Planetary Exploration Timelines Planetfest 2008 Pluto and Charon Pluto Top Ten Postcards from Venus Private Missions Rosetta Saturn Search for Extraterrestrial Intelligence SMART-1 SOHO Space Imaging Spitzer Space Telescope Stardust Trans-Neptunian Objects Ulysses Uranus Venus Venus Express Voyager Weekly Planetary Radio Trivia Contest

Space Topics: Uranus

Uranus' Moon Umbriel

Click to enlarge > A processed view fits color from more distant observations of Umbriel to the highest-resolution photo obtained by Voyager 2. Doughnut-shaped Wunda is on the equator near the left side of the image. Credit: NASA/JPL/Ted Stryk

Diameter: 1,169.4 kilometers
Orbital distance: 266,000 kilometers from Uranus
Orbital period: 4.14 days
Discovery: 1851 by William Lassell

Umbriel has the darkest and oldest surface of Uranus’ five major moons.  This is in sharp contrast to Ariel, which has similar physical properties to Umbriel, but a much more interesting surface.  Only one feature stands out prominently, a 40-kilometer-diameter bright circle called Wunda, which is located on Umbriel’s equator.  Wunda could be a relatively fresh impact crater, or (less likely) a methane volcano.