Categories Astronomy M 57 Post author By Luca Zanini Post date April 17, 2021 No Comments on M 57 M 57 or NGC 6720 is a planetary nebula in the constellation of Lyra and it is what remains of a supernova explosion.At its center there is a white dwarf which is what remains of the supernova core. Tags m57, ngc6720, planetary nebula ← M 13 → My first photos of Jupiter Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Email * Website Δ This site uses Akismet to reduce spam. Learn how your comment data is processed.