Webcomic artist Randall Munroe found a simple way to illustrate just how massive the black hole seen in Wednesday’s viral photo is.

According to NASA, the black hole at the center of Messier 87 is 6.5 billion times the mass of the Sun, and Munroe’s April 10 entry on xkcd helps illustrate that.

M87 is an elliptical galaxy some 55 million light-years from Earth.