A massive emission nebula in Monoceros, roughly 5,000 light-years away, spanning about 130 light-years across — large enough that five full moons would fit inside it. At its centre sits NGC 2244, a cluster of young, hot O- and B-type stars whose intense ultraviolet radiation ionises the surrounding hydrogen and has blown a cavity in the middle of the cloud. The result is the distinctive rose-like ring shape, with petals of glowing gas radiating outward.

The Rosette is one of the most photogenic deep-sky objects. Its combination of scale, brightness, and intricate structure makes it a favourite among astrophotographers, and it responds beautifully to narrowband imaging where the different emission lines reveal layered detail invisible in broadband.