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Comment by murat124 | Hacker News Reader

This image apparently has not captured as much attention as the image of M87, but anyway, I have a question, maybe someone with the knowledge can answer:

Between the images of M87 and Sgr A, one noticeable difference is that the image of M87 appears to have a single cluster of light "below" the blackhole whereas the image of Sgr A has three surrounding the blackhole. Is this because of the mass and spin differences between the two blackholes?

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Likely it is not about the mass, but about the arrangement of clumps of matter circling around the super massive black holes in the accretion disk. During the presentation they speak about much shorter time-scales for Sgr A* in comparison with M87, saying that for Sgr A* they were "making the image while it was changing" [1]. Also see other variations of the image (many teams analyzed data independently) here [2].

1. https://www.youtube.com/watch?v=rIQLA6lo6R0&t=1930s

2. https://physicsworld.com/wp-content/uploads/2022/05/First-SG... from https://iopscience.iop.org/article/10.3847/2041-8213/ac6429

> This image apparently has not captured as much attention as the image of M87

To be fair, to most non-scientific people the two photos look basically the same, and "orange halo" kinda loses it's appeal quickly

The first image of a black hole is cool to everyone, an image of a black hole in the center of the Galaxy is cool to a vastly smaller group I’d imagine.

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