NGC2403 & An Experiment

[JohnSadlerAstro]

Hi,

My official first light with the second hand NEQ6! I'm really pleased with its performance in all aspects, it's enabling me to get some good FWHMs on long subs and take advantage clear skies to the full. Sadly my camera, a modded 1000d is not so happy these days--ive noticed that noise is increasingly becoming an issue. Either this is because im imaging fainter objects or theres something about to break, Im not sure. ? 

I decided to try something a bit different this time, as the image itself isn't amazing from the aesthetic point of view. NGC2403 is almost a clone of M33 the Triangulum Galaxy, but is a tiny bit dimmer in surface magnitude so its an awkward one. There was baad gradient at the top and bottom from who knows what, and the colour just wouldn't work as a result. But then I noticed there were a lot of fuzzies in the background and thought it was time to give them some attention.

 

• 130PDS on NEQ6
• Guided with PHD2, ASI120MC & 50mm guider
• EOS 1000D at ISO 800, 200sec subs
• ~ 3hr 30 mins
• Stacked DSS, Processed Star Tools & GIMP
• Tables in Word, compiled in GIMP
• Identification from SIMBAD & NASA NED
   

The crops are all 100x100 pixels, so thats around 181 x 181 arc sec. Some of these are quite faint, like the NVSS which shows up as a really odd blue dot contrasted against the LP.

I compiled the results from SIMBAD and NED searches into a table. 9 of the galaxies I cant identify so I just recorded their estimated magnitudes and exact positions along with some notes. Perhaps someone will be able to help out with these? Data was very incomplete even for the identifiable ones, so I added some extra data of my own, which appears in the table in [square brackets]. (I used SDSS data from SIMBAD quite a bit to get the galaxy types.)

There's a lot of interesting stuff in this part of the sky, some blue dwarfs, lots more galaxies and galaxy clusters that I missed, and several beautiful colour-contrasting binaries. I could have started identifying some of the objects within 2403 itself, as well but ran out of time (and patience)!  

This is the original, theres a particularly notable blue dwarf about one 2403 diameter above the main galaxy, it shows up as something looking a lot like a hot pixel. 

 

I'm aware that attempting to identify all the galaxies in images and cataloguing them isn't standard practice (probably because its *very* tedious ), but it would be interesting to hear people's views on this, and what the strangest objects that you've found are? 

Clear skies!

John