Located in the constellation of Cassiopeia, SNR G107.5-5.2 is a gigantic and extremely delicate supernova remnant, spanning approximately 3 degrees across the sky.

Discovered in 2023 by Bray Falls, Marcel Drechsler and their team, this structure is distinguished by its remarkably delicate ionized oxygen emission lines (OIII 500.7 nm). Its shock waves, forming what appear to be vast gaseous “draperies”, have earned the object the nickname The Nereides, in tribute to the sea nymphs of Greek mythology.