Two moons of Uranus might collide

Date:8 September 2017 Tags:, , , ,

A new paper predicts that two of the moons of Uranus are on a collision course with each other. Desdemona and Cressida, two small moons, are on pace for a crash in approximately a million years.

By David Grossman

The collision was predicted by a study uploaded to arVix by two researchers at the University of Idaho and one from Wellesley College. Uranus is the fourth-largest planetary mass in the solar system and has both a ring system and a remarkable 27 moons in its orbit. The moons are divided into 13 inner moons, 5 major moons, and 9 irregular moons. Mankind’s first real encounter with most of these moons was not until the 1986 Voyager 2 flyby.

The researchers were studying the ring system when they noticed an odd orbit. It wasn’t round or elliptical, but instead resembled a triangle. The odd shape, according to the study, is because of one of the inner moons, Cressida. Named after a title character in Shakespeare’s Troilus and Cressida, the moon Cressida’s gravitational pull is exaggerated. This is because it keeps pace with Uranus itself, and that extra pull makes the rings slightly triangular.

Troilus and Cressida is a tragedy, and the same can be said for the moon’s gravitational pull. That pull, which gives the Uranian ring system a unique quality, is also pulling Cressida closer and closer to Desdemona, another inner moon named after a Shakespeare character. The two currently orbit a mere 900 kilometres apart from each other. The study believes that this gravitational pull will ultimately cause a collision.

Beyond their eventual destruction, we know virtually nothing about Desdemona or Cressida. But a closer study of Uranus (and its sibling ice giant, Neptune), might give a better understanding of its numerous and fascinating moons.

From: PM USA