Here's an image I've been working on and researching on and off since June. It was quite low then and is a lot lower now so I'm not going to get any more time on it this year. It's not very good but it won't get any better sitting on my hard drive - so here goes.
I became attracted to imaging NGC 4395 when I found some press reports about the galaxy's central black hole and decided to try and have a look myself. Apparently the black hole in the center of NGC 4395 has a mass less than a million times that of the Sun. That might sound like a lot, but it's many times smaller than the normal "supermassive" black holes usually found in the centre of galaxies.
Typically, in the centres of galaxies, there are black holes that are a million to a billion solar masses. This one is less than a million - it could be around 300,000 to 400,000 solar masses.
It's not just the black hole that's unusual - its host galaxy is odd as well. While most galaxies are disk-shaped with a bulge in the middle, NGC 4395 is essentially flat; it has no central bulge. And this unusual shape may be linked to the size of the black hole: it may that the black hole has already "eaten" all the stars in the center of the galaxy. This would explain why the black hole doesn't seem to be growing, as well as the galaxy's odd shape.
The black hole at the center of NGC 4395 is located some 8-14 million light-years from Earth.
References:
www.astronomy.com/asy/default.aspx?c=a&id=2905iopscience.iop.org/1538-4357/588 ... .text.html
hubblesite.org/newscenter/archiv ... 3/19/text/
My image taken on 17th June, using my 10" F4.8 Reflector and SX H9C camera, comprises 53 x 120 sec exposures. It is a pretty faint and difficult subject - magnitude 10.7 but surface brightness only 15.4 mag/square arcmin.
I did a search on Simbad and found that NGC 4395 is surrounded by a swarm of quasars, a couple of which I've been able to locate on my image.
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