Characteristics
Like all lunar maria, Oceanus Procellarum was formed by ancient basaltic flood volcanic eruptions that covered the region in a thick, nearly flat layer of solidified magma. Unlike the other lunar maria, however, Oceanus Procellarum is not contained within a single well-defined impact basin (evidence for a "Procellarum basin" of impact origin is equivocal). Around its edges lie many minor bays and seas, including Mare Nubium and Mare Humorum to the south. To the northeast, Oceanus Procellarum is separated from Mare Imbrium by the Carpathian Mountains. On its north-west edge lies the 32 km wide Aristarchus ray crater, which is considered as the brightest feature on the Near side of the Moon. Also, the more-prominent ray-crater Copernicus lies within the eastern edge of the mare, distinctly with its bright ray materials sprawling over the darker material. On the northern edge of Oceanus Procellarum lies Sinus Roris.
Read more about this topic: Oceanus Procellarum