What is "ammonius"

Ammonius is a bowl-shaped lunar impact crater with a slightly raised rim. It is located on the floor of the walled plain Ptolemaeus, about 30 kilometers northeast of the crater midpoint. In the past this crater was identified as Ptolemaeus A, before being named by the IAU in 1976.

Just to the north on the lava-flooded floor of Ptolemaeus is a relatively prominent "ghost" crater: the discernible buried rim of a pre-existing crater. The diameter of this ghost crater is nearly double that of Ammonius, and is currently identified as Ptolemaeus B.

Ammonius may refer to:

• Ammonius Lithotomos (3rd century BC), Greek lithotomist
• Ammonius of Athens (1st century AD), philosopher and teacher of Plutarch
• Ammonius Saccas (3rd century AD), Neoplatonist philosopher and teacher of Plotinus
• Ammonius of Alexandria (Christian) (3rd century AD), Christian writer confused with Ammonius Saccas
• Ammonius the Hermit (4th century) celebrated abbot and desert father, also known as Ammonas
• Ammonius Hermiae (5th century AD), Alexandrian philosopher
• Ammonius Grammaticus, supposed author of a grammatical treatise
• Ammonius (genus), a genus of the spider family Barychelidae
• Ammonius (crater), a lunar crater
• Ammonius (monk)

Ammonius (c. 5th Century AD) was a Christian monk, involved in the power struggle between the bishop Cyril of Alexandria and the Praefectus augustalis Orestes.

Ammonius was part of a group of supporters for the bishop Cyril, composed of both Parabalani and Nitrian monks. Whether he was a member of the Parabalani or the Nitrian Monks in support of Cyril during his early reign is not made clear.

He, along with his fellow monks, confronted the Prefect riding in his open chariot in the streets of Alexandria. During the confrontation, he hurled a stone towards Orestes which struck him in the head. The cut spilled enough blood to cover his face nearly killing him. The monks then fled the scene from the prefect's guards and his supporters. He did not manage to flee in time and was captured by the guards and tortured to death. To show appreciation, Cyril seized his body and had his funeral at the church. During the proceedings, Cyril proclaimed him a martyr and saint and renamed him Saint Thaumasius (the Wonderful). This title was soon stripped by Cyril after fellow Christians who were embarrassed by his actions began to question this decision.