NGC 4395

[alan4908]

NGC 4395 is low surface brightness dwarf galaxy about 14 million light years distant in Canes Venatici.  Although visually dim, the apparent size of the galaxy is quite large, about 13’ x 11’. Unusually, it does not have a central bulge of stars in its central core and is significantly variable in X-Ray emissions with luminosity emissions varying by a factor of two within 300s. Three star forming regions, have separate designations (NGC 4401, 4400, 4399).

Most galaxies contain central black holes and radiation is produced as objects fall into them.  For NGC 4395, the core is extremely dim, so the mass of the associated black hole mass is believed to be extremely small, probably somewhere between 10,000 and 400,000 solar masses, making it one of the smallest black holes found in galaxies.

The LRGB image below has an Ha blend into the red channel and was taken by my Esprit 150 and represents about 18 hours integration time.

Alan

NGC 4395

NGC 4395 (annotated)

LIGHTS: L:32, R:17, G:15, B: 18 x 600s; Ha:8 x 1800s. DARKS:30, FLATS:40, BIAS:100 all at -20C.

[geeklee]

Another beautiful and rare to see (for me) set of galaxies.  NGC4399 is fascinating with that tantalising bit of detail.  Thanks for the information in the write up too.

[scotty38]

Blimey, another great image. I'd have had to start years ago to get 18hrs of data 🙂

[Dave61]

What a cracking image that is, very nice.

[alan4908]

20 hours ago, geeklee said:

Another beautiful and rare to see (for me) set of galaxies.  NGC4399 is fascinating with that tantalising bit of detail.  Thanks for the information in the write up too.

Thanks Lee - yes, NGC 4399 is very strange looking - looks a little like a planet made of stars. 

20 hours ago, scotty38 said:

Blimey, another great image. I'd have had to start years ago to get 18hrs of data

Well, given poor UK weather and the fact that I don't have a clear horizon, it does take me rather a long time to get this amount of data. Due to these two factors, I do rely on my automated imaging set up a lot !

20 hours ago, Dave61 said:

What a cracking image that is, very nice.

Thanks !  

[Clarkey]

Really great image. I like the processing too. Not 'overdone'.

Might put this on my list for next year.

[alan4908]

On 14/04/2021 at 22:33, Clarkey said:

Really great image. I like the processing too. Not 'overdone'.

Might put this on my list for next year.

Thanks for the comment - if you do attempt this, then I'd suggest quite long exposures for the outer arms since I found them very faint. 

Alan