Helicon is a small lunar impact crater that is located on the north part of the Mare Imbrium.
The crater was named after 4th century BC Greek astronomer Helicon of Cyzicus,[1] a friend and disciple of Plato.
[2] To the northwest is the prominent Sinus Iridum, a mountain-ringed bay on the mare.
Helicon is a nearly circular formation with inner walls that curve down to a relatively flat floor.
According to convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Helicon.