Picture of the day

2026-03-31

Uranus's Largest Moon: Titania

Titania's tortured terrain is a mix of canyons, cliffs, and craters. NASA's interplanetary robot spacecraft Voyager 2 passed the largest moon of Uranus in 1986 and took the feature picture. That the trenches of Titania resemble those on another moon of Uranus, Ariel, indicate that Titania underwent some violent surface event possibly related to water freezing and expanding in its distant past. Although Titania is Uranus's largest moon, it is only about half the radius of Triton - the largest moon of Uranus's sister planet Neptune, which itself is slightly smaller than Earth's Moon. Titania, discovered by William Herschel in 1787, is essentially a large dirty iceball that is composed of about half water-ice and half rock. There is recent speculation that radioactive heating melts some underground ice into oceans.

Recent Images

2026-03-30

Peculiar Elliptical Galaxy Centaurus A

2026-03-29

A Message from Earth

2026-03-28

Robert Goddard and Nell

2026-03-27

Hickson 44 in Leo