5 ms·
From reddit: >"Hi, regarding the image itself: What I don't understand is why does it look like a donut and not a bright sphere? Assuming the black hole is act
by nonbel 8y ago
From reddit:
>"Hi, regarding the image itself: What I don't understand is why does it look like a donut and not a bright sphere? Assuming the black hole is actually spherical and not disc shaped, I would expect the Halo to be spherical and surrounding the black hole? so all we would see would be the ball of bright gas, even though there is a black hole in the middle?"
This is also what I would have expected.
- petschge 8y agoThings don't simply form a halo around a black hole. Instead you get a relatively flat accretion disk of things that orbit around the black hole.
- Sharlin 8y agoThe same reason planetary rings, solar systems, and (spiral) galaxies are flat: friction and conservation of angular momentum. Internal drag forces will eventually cancel out velocity components perpendicular to the plane of rotation, turning a cloud into a flat plane.
- VikingCoder 8y agoThis was a great explanation: https://www.youtube.com/watch?v=zUyH3XhpLTo https://www.youtube.com/watch?v=zUyH3XhpLTo
- db48x 8y agoMaterial can come in towards the black hole from any angle. However, because matter can't just pass through other matter, matter travelling in the wrong directions will collide more frequently than matter travelling in the right direction. Because of the conservation of angular momentum, the "right" direction will depend on the average angular momentum of everything in the cloud that is collapsing into the disk. You might be interested to know that this is the same reason all the planets in our solar system orbit in the same disk: all the matter that is now in our solar system was originally a very thin cloud of gas with a small amount of overall angular momentum. As gravity drew it together it flattended out into a disk and eventually the clumps became planets (and the sun in the middle.)