Messier 57 is a planetary Nebula with all the consequences. It was formed about 7,000 years ago, when a dying red giant star expelled its shell of ionized gas to form the nebula. And this star then became a white dwarf – a hot, dense stellar remnant roughly the size of the Earth and surface […]
This post first appeared on Astrojolo - Astronomy And Astrophotography, please read the originial post: here
