Supernova remnant
A supernova remnant was a gaseous structure resulting from a star exploding in a supernova. Examples include the MacPherson Nebula and Arachna. (; )

In July of 2151,  detected a J'ral class supernova remnant approximately three light years off their course. However, they opted to study another nearby object instead. ()

The Briar Patch was flooded with radiation from supernova remnants. ()

In 2375, Captain Kathryn Janeway used studying a supernova remnant as an excuse for entering a restricted part of Devore space. ()

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Celestial objects