A small telescope or even 10×50 mm binoculars will reveal a beautiful cluster of large and interesting lunar craters -Theophilus, Cyrillus and Catharina.
Theophilus is an exceptional formation 60 miles in diameter with steep walls extending 2.7 miles unto the crater’s floor. There is a spectacular mountain peak in the center of the crater.
Cyrillius lies to the west of Theophilus in the picture. It is about 61 miles across and about 2 miles deep and is somewhat older than Theophilus. The crater has three distinct peaks near its center but not as impressive as the massive peak in the Theophilus crater.
Lastly is Catharina. This crater is the oldest and most eroded of the trio. Catharina’s walls and surface floor have been greatly damaged by almost four billions of years of meteoric bombardment. It remains, however a steep walled crater even after all of these years.
To observe the Theophilus, Cyrillus and Catharina trio look for them 5 days after New Moon or 4 days after the Full Moon.
Image taken August 22, 2016.