Starship Asterisk*

I have a question (actually, several) about Black Holes: If these things are at the center of some galaxies, does this explain the whirlpool shape that we see in images? I think of the way water drains out of a bathtub -- is that what's going on, on a galactic scale, except it's light and matter and...

I love the APOD and visit every single day for inspiration and information. But one request or suggestion keeps coming up im my mind, so here it is: Would it be possible to add a small legend to the images, or add a phrase in the text, that gives a human scale when the image is of a land feature? Fo...