Cyrillus (crater)

Template:Short description Template:Infobox Lunar crater

Cyrillus is a lunar impact crater located on the northwest edge of Mare Nectaris. Intruding into the northeast rim is the slightly larger, and younger crater Theophilus. To the south is another prominent crater named Catharina. Together these three craters form a prominent trio in the southeast quadrant of the Moon. To the northwest is Ibn-Rushd. Cyrillus is named after Saint Cyril of Alexandria, a 5th-century Patriarch and theologian.<ref>Template:Gpn</ref>

The floor of Cyrillus contains a reduced central hill and the considerable crater Cyrillus A. The walls of the broken formation of Cyrillus remain intact until the point of junction with Theophilus.<ref name="b">Moore, Patrick (2001). On the Moon. Sterling Publishing Co.. Template:ISBN. p. 81, 209</ref> Slightly northeast of its center, three rounded mountains rise to heights of 1,000 metres above Cyrillus' floor: Cyrillus Alpha, Delta, and Eta.<ref>Grego, Peter (2005). Moon Observer's Guide. Springer. Template:ISBN. p. 207</ref>

A tiny crater with bright rays on the east side of Cyrillus has been named Shioli.<ref>Template:Gpn</ref> A point to the east of Shioli is the proposed landing site of Japan's SLIM lander.<ref>Moon Monday #144: On the most precise planetary landing attempt by SLIM, sprawling SLS rocket costs, and more, Jatan’s Space, SEP 11, 2023.</ref><ref>SLIM, JAXA website in Japanese</ref><ref>On the Way to Shioli Crater, LROC image team, Posted by Mark Robinson on November 07, 2023 18:51 UTC.</ref>

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Cyrillus.<ref>Template:Cite book</ref>