Draft:The Nereides Nebula, SNR G107.5-5.2

The Nereides Nebula or SNR G107.5-5.2 is large a supernova remnant in the constellation Cassiopeia, discovered in 2023 by amateur astronomers Bray Falls and Marcel Drechsler. SNR G107.5-5.2 has an apparent angular diameter of 3 degrees, comparable to the nearby Cygnus Loop Supernova Remnant. The remnant itself is primarily composed of [ Oiii] emission from doubly ionized oxygen, suggesting the supernova occurred from a type 1B stripped core-collapse supernova.

SNR G107.5-5.2 has remained undetectable to professional observatories due to a lack of bright radio, x-ray, or ultraviolet emission. The remnant is only weakly visible in optical wavelengths like hydrogen-alpha, Sulfur-ii, and Oxygen-iii.

The Nereides Nebula gets its name from the sea nymph daughters of the god Nereus, since the remnant is located within Cassiopeia, and the remnant visually looks like a group of blue sea nymphs.

The nebula was first photographed as an international collaboration between three refractor telescopes, located in California, Morocco, and France.