Blackhole at the center of each galaxy, think again

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Chandra Observations

I'm surprised these haven't been mentioned in this context:

http://http://www.sciencedaily.com/print.php?url=/releases/2005/01/050111090506.htm

I think stuff is awesome because it demonstrates well both the curvature of space and the illusion of dimension from outside the core. That is, while we might measure the diameter in light years from our perspective using angular measurement the actual dimensions from the perspective within the core may very well be much larger.

Clearly our understanding of "Black Holes" is still in its infancy.
 
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The evidence indicating SMBH reside in the cores of most, if not all reasonably sized galaxies, is not derived from observations of individual stars. That is well beyond our technology. It is hard enough to resolve individual stars in the core of our own galaxy. Some armchair material to consider:

http://webdisk.berkeley.edu/~kshapiro/cosmo_project.htmlhttp://webdisk.berkeley.edu/~kshapiro/cosmo_project.html
 
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SpaceTiger said:
This is an observational upper limit, meaning the black hole must be smaller than that (we can't actually see it). In actuality, it's probably more like 25 light-seconds wide.
The 20 light minutes probably refers to the diameter of an accretion disc around the BH.

Garth
 
Garth said:
The 20 light minutes probably refers to the diameter of an accretion disc around the BH.

No, we have not imaged an accretion disk around the black hole in our galaxy. They simply give numbers like this to support the idea that the object is a black hole. They can't acutally observe the event horizon itself, so they don't say that it's light-seconds across. They look at the motions of objects around it and use those place to dynamical limits on the extent of the object.