> What astronomers hope to finally see when they add up all the signals is a halo of light surrounding a dark circle—the shadow of the black hole. The crescent

> What astronomers hope to finally see when they add up all the signals is a halo of light surrounding a dark circle—the shadow of the black hole. The crescent of light comes from luminous gases, heated to hundreds of billions of degrees, that orbit just outside the black hole, tracing the region just beyond the event horizon. Probably some sort of ring image captured from the side or something like the artist's rendering in the article maybe.