Titania (moon)

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Titania
Titania (moon) color cropped.jpg
Click image for description
Discovery
Discovered by William Herschel
Discovered in January 11, 1787
Orbital characteristics
Semi-major axis 435,910 km
Mean radius 436,300 km
Eccentricity 0.0011
Orbital period 8.706 d
Inclination 0.340° (to Uranus' equator)
Is a moon of Uranus
Physical characteristics
Mean diameter 1577.8 km

(0.1237 Earths)

Surface area 7,820,000 km²
Volume 2,057,000,000 km³
Mass 3.526×1021 kg

(5.9×10−4 Earths)

Mean density 1.72 g/cm³
Surface gravity 0.378 m/s2 (~0.039 g)
Escape velocity 0.77 km/s
Rotation period synchronous
Axial tilt zero
Albedo 0.27
Apparent magnitude 13.73
Surface temp.
min mean max
 ? K ~60 K  ? K
Atmospheric pressure  

Titania is the biggest moon of Uranus and the eighth biggest moon in the Solar System.

Discovery[change | edit source]

Titania was found on January 11, 1787 by William Herschel. He reported it and Oberon the same year.[1] He later reported four more moons, which turned out to be spurious.[2]

Name and pronunciation[change | edit source]

The names of Titania and the other four moons of Uranus then known were suggested by Herschel's son John Herschel in 1852 at the request of William Lassell, who had found Ariel and Umbriel the year before.[3] Lassell had earlier supported Herschel's 1847 naming scheme for the seven then-known moons of Saturn and had named his newly-found eighth moon Hyperion in accordance with Herschel's naming scheme in 1848.

All of the moons of Uranus are named for characters from Shakespeare or Alexander Pope. Titania was named after Titania, the Queen of the Faeries in A Midsummer Night's Dream.

Shakespeare's character's name is pronounced how to say: /tɨˈtɑnjə/, but the moon is often pronounced /taɪˈteɪniə/, by analogy with the familiar chemical element titanium.

It is also designated Uranus III.

Physical characteristics[change | edit source]

So far the only close-up images of Titania are from the Voyager 2 probe, which photographed the moon during its Uranus flyby in January, 1986. At the time of the flyby the southern hemisphere of the moon was pointed towards the Sun so only it was studied.

Although what its interior is made up of is uncertain, one model suggests that Titania is made of about 50% water ice, 30% silicate rock, and 20% methane-related organic compounds.

Surface features[change | edit source]

Surface features on Titania are named for characters from plays by William Shakespeare.[4] Chasms on Titania are called chasmata. Escarpments here are called rupes. They are named after the places where plays by Shakespeare happen. craters on Titania are named after female characters in the plays.

A major surface feature is a huge canyon that dwarfs the scale of the Grand Canyon on Earth and is in the same class as the Valles Marineris on Mars or Ithaca Chasma on Saturn's moon Tethys.

Named surface features on Titania[5]
Feature Named after Type Length (diameter), km Coordinates
Belmont Chasma Belmont, Italy (The Merchant of Venice) Chasma 238 8°30′S 32°36′E / 8.5°S 32.6°E / -8.5; 32.6
Messina Chasmata Messina, Italy (Much Ado About Nothing) 1,492 33°18′S 335°00′E / 33.3°S 335°E / -33.3; 335
Rousillon Rupes Roussillon, France (All's Well That Ends Well) Rupes 402 14°42′S 23°30′E / 14.7°S 23.5°E / -14.7; 23.5
Adriana Adriana (The Comedy of Errors) Crater 50 20°06′S 3°54′E / 20.1°S 3.9°E / -20.1; 3.9
Bona Bona (Henry VI, Part 3) 51 55°48′S 351°12′E / 55.8°S 351.2°E / -55.8; 351.2
Calphurnia Calpurnia Pisonis (Julius Caesar) 100 42°24′S 291°24′E / 42.4°S 291.4°E / -42.4; 291.4 (Calphurnia crater)
Elinor Eleanor of Aquitaine (The Life and Death of King John) 74 44°48′S 333°36′E / 44.8°S 333.6°E / -44.8; 333.6
Gertrude Gertrude (Hamlet) 326 15°48′S 287°06′E / 15.8°S 287.1°E / -15.8; 287.1
Imogen Imogen (Cymbeline) 28 23°48′S 321°12′E / 23.8°S 321.2°E / -23.8; 321.2
Iras Iras (Antony and Cleopatra) 33 19°12′S 338°48′E / 19.2°S 338.8°E / -19.2; 338.8
Jessica Jessica (The Merchant of Venice) 64 55°18′S 285°54′E / 55.3°S 285.9°E / -55.3; 285.9
Katherine Katherine (Henry VIII) 75 51°12′S 331°54′E / 51.2°S 331.9°E / -51.2; 331.9
Lucetta Lucetta (The Two Gentlemen of Verona) 58 14°42′S 277°06′E / 14.7°S 277.1°E / -14.7; 277.1
Marina Marina (Pericles, Prince of Tyre) 40 15°30′S 316°00′E / 15.5°S 316°E / -15.5; 316
Mopsa Mopsa (The Winter's Tale) 101 11°54′S 302°12′E / 11.9°S 302.2°E / -11.9; 302.2
Phrynia Phrynia (Timon of Athens) 35 24°18′S 309°12′E / 24.3°S 309.2°E / -24.3; 309.2
Ursula Ursula (Much Ado About Nothing) 135 12°24′S 45°12′E / 12.4°S 45.2°E / -12.4; 45.2
Valeria Valeria (Coriolanus) 59 34°30′S 4°12′E / 34.5°S 4.2°E / -34.5; 4.2

Occultation[change | edit source]

On September 8, 2001, Titania occulted a faint star; this was a chance to both refine its diameter and ephemeris, and to detect any extant atmosphere. The data revealed no atmosphere to a surface pressure of 0.03 microbars; if it exists, it would have to be far thinner than that of Triton or Pluto.[6][7]

Other websites[change | edit source]

Notes[change | edit source]

  1. Herschel, "An Account of the Discovery of Two Satellites Revolving Round the Georgian Planet", Philosophical Transactions of the Royal Society of London, Vol. 77, pp. 125-129, 1787; and "On George's Planet and its satellites", Philosophical Transactions of the Royal Society of London, Vol. 78, pp. 364-378, 1788.
  2. "On the Discovery of Four Additional Satellites of the Georgium Sidus; The Retrograde Motion of Its Old Satellites Announced; And the Cause of Their Disappearance at Certain Distances from the Planet Explained", Philosophical Transactions of the Royal Society of London, Vol. 88, pp. 47-79, 1798.
  3. http://adsabs.harvard.edu//full/seri/AN.../0034//0000169.000.html Adsabs.harvard.edu Retrieved on 05-19-07
  4. Strobell, M.E.; Masursky, H. (1987). "New Features Named on the Moon and Uranian Satellites". Abstracts of the Lunar and Planetary Science Conference 18: 964–65.
  5. USGS/IAU. "Titania Nomenclature Table Of Contents". Gazetteer of Planetary Nomenclature. USGS Astrogeology. http://planetarynames.wr.usgs.gov/Page/TITANIA/target. Retrieved 2012-02-23.
  6. http://www.obspm.fr/actual/nouvelle/mar02/titania.en.shtml Obspm.fr Retrieved on 05-19-07
  7. http://www.lesia.obspm.fr/~titania/results.html Lesia.obspm.fr Retrieved on 05-19-07

Other websites[change | edit source]