Question: What is the name of the largest known crater on Uranus's moon Titania, named after the mother of Hamlet in Shakespeare's work?
Context: Uranus is the seventh planet of the Solar System; it has 27 known moons, all of which are named after characters from the works of William Shakespeare and Alexander Pope.  Uranus's moons are divided into three groups: thirteen inner moons, five major moons, and nine irregular moons.  The inner moons are small dark bodies that share common properties and origins with Uranus's rings.  The five major moons are massive enough to have reached hydrostatic equilibrium, and four of them show signs of internally driven processes such as canyon formation and volcanism on their surfaces.  The largest of these five, Titania, is 1,578 km in diameter and the eighth-largest moon in the Solar System, and about one-twentieth the mass of the Moon.  The orbits of the regular moons are nearly coplanar with Uranus's equator, which is tilted 97.77° to its orbit.  Uranus's irregular moons have elliptical and strongly inclined (mostly retrograde) orbits at large distances from the planet. Rousillon Rupes is a scarp ("rupes" is Latin for "cliff") on the surface of the Uranian moon Titania named after "Bertram, count of Rousillon" (an Elisabethan English misspelling for Roussillon) in William Shakespeare's comedy All's Well That Ends Well.  The 402 km long feature is a normal fault situated near the equator and running perpendicular to it.  The scarp cuts impact craters, which probably means that it was formed at a relatively late stage of moon's evolution, when the interior of Titania expanded and its ice crust cracked as a result.  Rousillon Rupes has only few crater superimposed on it, which also implies its relatively young age.  The scarp was first imaged by Voyager 2 spacecraft in January 1986. Ursula is a large crater on Uranus's moon Titania.  It is about 135 km across, and is cut by Belmont Chasma.  It is named after Hero's attendant in William Shakespeare's comedy Much Ado About Nothing. Gertrude is the largest known crater on Uranus's moon Titania.  It is about 326 km across, 1/5 of Titania's diameter.  It is named after the mother of Hamlet in William Shakespeare's play Hamlet.  Features on Titania are named after female Shakespearean characters. Messina Chasma is the largest canyon on the surface of the Uranian moon Titania and is named after a location in William Shakespeare's comedy Much Ado About Nothing.  The 1492 km long chasma is made of two normal faults running NW–SE, which bound a down-dropped crustal block forming a structure called graben.  The canyon cuts impact craters, which probably means that it was formed at a relatively late stage of the moon's evolution, when the interior of Titania expanded and its ice crust cracked as a result.  Messina Chasma has only a few crater superimposed on it, which also implies it is relatively young structure.  The chasma was first imaged by the Voyager 2 spacecraft in January 1986. Turgis is the largest known crater on Saturn's moon Iapetus.  It is 580 km in diameter, 40% of the moon's diameter and one of the larger craters in the Solar System.  It is named after a Saracen baron, "Turgis of Turtelose (Tortosa)". In William Shakespeare's play "Hamlet", Gertrude is Hamlet's mother and Queen of Denmark.  Her relationship with Hamlet is somewhat turbulent, since he resents her marrying her husband's brother Claudius after he murdered the King (young Hamlet's father, King Hamlet).  Gertrude reveals no guilt in her marriage with Claudius after the recent murder of her husband, and Hamlet begins to show signs of jealousy towards Claudius.  According to Hamlet, she scarcely mourned her husband's death before marrying Claudius. Hamlet is the largest crater on the known part of the surface of Uranus' moon Oberon.  It has diameter of about 206 km and is named after the title character of the play Hamlet, by William Shakespeare.  The crater has a dark floor and is surrounded by a system of bright rays, which are ice ejecta deposited during the impact event.  The nature of the dark material on the floor is not known, but it may have erupted from depth.  The crater was first imaged by the Voyager 2 spacecraft in January 1986. Yangoor is the largest known crater on the surface of the Uranian moon Ariel.  The name comes from a spirit that brings day in Australian Aboriginal mythology.  It is about 80 km in diameter and is located approximately 450 km from Ariel's south pole.  The northwestern edge of the crater was erased by formation of ridged terrain.  The crater lacks bright ejecta deposits and was imaged for the first time by the "Voyager 2" spacecraft in January 1986. Titania is the largest of the moons of Uranus and the eighth largest moon in the Solar System at a diameter of 1578 km .  Discovered by William Herschel in 1787, Titania is named after the queen of the fairies in Shakespeare's "A Midsummer Night's Dream".  Its orbit lies inside Uranus's magnetosphere.
Answer: Gertrude