Because we're basically looking at it from the "top" of the accretion disk. That's not exactly correct, but the way light and gravity mix the image isn't perfectly uniform.

The brightest edge of the picture is the matter heading toward us, where as the darker edge it's heading away.

The image you shared has a bit of artistic touch. It's hard to visualize how a disk of matter spinning in one plane can emit light in the massively warped space around a black hole.

[–] [email protected] 2 points 2 months ago* (last edited 2 months ago) (1 children)

Because we're basically looking at it from the "top" of the accretion disk.

I'm not sure which way M87 points, but for Saggitarius A*, shouldn't we be seeing it pretty much edge on? Our solar system is in the plane of the Milky Way.

[–] Telodzrum 6 points 2 months ago

The Solar System sits about 20.5 parsecs above the galactic plane, so not really edge on.

[–] Khanzarate 4 points 3 months ago

Possible we're looking at the top and the band is a disk around it. Dunno for sure.