Charles Messier was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the Messier objects, referred to with the letter M and their number between 1 and 110.
Some of these are now known to be planetary nebulae

Click on each image for more details.
Image description
M37 / IPHASX J055226.2+323724
Image description
M 57
Image description
M 76
Image description
M 97 with Halo