FERNANDO OLIVEIRA DE MENEZES
So 174mm and so290mc
Positioned further south of this beautiful group of craters is Catharina, 100 km in diameter and 3.1 km deep. Its rough, irregularly contoured walls host the smaller impact marks. Catharina is clearly the most eroded and thus the oldest of the trio.
The middle crater, Cyrillus, is not much younger. Note the seemingly huge “channel” that connects Cyrillus to Catharina. In reality, the connection is the result of many impacts and collapses.
Cyrillus is 98 km in diameter and only 3.1 km deep, although its inner slopes are more prominent and give the crater a deeper impression. On the floor of Cyrillus, near the center, there are three prominent peaks.
The youngest crater of the three is Theophilus, with its 100 km in diameter and 3.2 km deep. It is, in itself, a spectacular formation. The outer edges surrounding the crater rise by about 1.2 km above the level of the outer roundness. The outer edges form a kind of “fortification” with steep and sloping walls, created by the debris of impact.
Its interior is a little deeper, presenting 3.2 Km below the level of external roundness. The interior of the Theophilus crater is very complex. Clearly its interior walls in the form of steps or curves of level, were very degraded by slides and collapses.