Ursula (crater)

Lore & Background

Ursula is a large impact crater on Uranus's moon Titania, with a diameter of about 135 km, making it the second-largest known impact feature on the moon after Gertrude. The crater is disrupted by a series of parallel chasms, and it is cut by Belmont Chasma. Ursula has a flat floor and what appears to be a central pit about 20 km in diameter, though this structure is more likely a series of depressions caused by multiple tectonic faults breaking up the crater floor. It is probably one of the youngest large impact craters on Titania. The crater is surrounded by smooth plains that have the lowest impact crater density of all geological units on the moon, though they are cut by Belmont Chasma. While these smooth plains could represent an ejecta blanket from the Ursula impact, the lack of similar deposits around Titania's other large craters suggests a cryovolcanic origin, making the regions around Ursula one of the only identified candidate cryovolcanic features on Titania.

Reader's Guide

Ursula's significance lies in its status as the second-largest impact crater on Titania and its association with smooth plains that may indicate cryovolcanic activity. The article notes that the smooth plains surrounding Ursula have the lowest impact crater density on the moon, which could be due to an ejecta blanket from the impact event obliterating nearby craters. However, the absence of similar deposits around other large craters on Titania suggests a cryovolcanic origin instead, making Ursula's surroundings one of the only candidate cryovolcanic features identified on the moon. This potential cryovolcanism may be analogous to the smooth plains observed on Saturn's moons Dione and Tethys. The crater itself is disrupted by tectonic faults and chasms, including Belmont Chasma, and its central pit is likely a result of these faults rather than a single impact structure. As probably one of the youngest large impact craters on Titania, Ursula provides insight into the moon's geological history, including impact processes and possible internal activity.

Did You Know?

• The crater is about 135 km across and is cut by Belmont Chasma.
• Ursula's name was officially adopted by the International Astronomical Union in 1988.
• The smooth plains around Ursula may be cryovolcanic, making them one of the only candidate cryovolcanic features on Titania.