Composite image of Arp 26, also known as M101 or the Pinwheel Galaxy.

X-rays from NuSTAR (green) show a supernova, on a visible light (KPNO, yellow and red) and far-UV (GALEX, blue) image of M101.

Credit: NASA, JPL-Caltech, NOIRLab, NSF, AURA, B. Grefenstette, R. Hurt
https://www.nustar.caltech.edu/image/nustar240125a