Object Of The Week February 14, 2020 ? The galaxies behind M 44

1 Attachment(s)

NGC 2624, NGC 2625, NGC 2637, NGC 2643, NGC 2647, IC 2388, UGC 4526

Galaxy Chain

Constellation: Cancer

RA: 08 41 36 (center of M 44)
DEC: +19 35 32 (center of M 44)

Mag: 14.5 and fainter

I wanted to write this OOTW 5 years ago already, when I made my observations of these galaxies, but unfortunately Sky and Telescope dedicated an article exactly to this so I chose a different object then. However, I still think this is a nice challenge so here we go!

My fascination with these galaxies started in 1998, when I was an undergrad student visiting the NRAO in Socorro, New Mexico, to work on VLA data for my graduation thesis. An Indian PHD student and me had discovered an amateur observatory just outside of Socorro and we quickly got permission to visit whenever we wanted and to use the 20? Dobson telescope that they had there. The library of NRAO had a copy of the Uranometria 2000 and I already noticed that several galaxies were plotted behind M 44. However, this was my first time this far south (the Netherlands are at a latitude of 52? north and so far I had only been to the South of France at 45? north) and my first time under a spring sky with such a big telescope. Therefore I spent my precious observing hours on many other interesting objects.

In 2010 I bought my 20? telescope and in 2011 I moved to Spain. Finally, in 2016 I took the opportunity to visit M 44 with the sole purpose of observing these galaxies. And I quickly found that this wasn?t at easy as expected. I had observed galaxies of magnitude 14.5 and fainter before, even going dow to magnitude 17. But trying to see these faint smudges next to the relatively bright stars of M 44 wasn?t easy. In the end I managed to see all NGC and IC galaxies and the brightest UGC galaxy that lie within the boundaries of M 44. There are more and fainter galaxies there but I didn?t try them. A map of them, created with SkySafari Pro on my MacBook, shows all galaxies down to magnitude 17.

Attachment 4211

For some reason the screenshot of SkySafari doesn't get displayed at its full resolution, so you can see the full file here: https://wvreeven.stackstorage.com/s/JpnNo3fszmn0yMKJ

Note that it displays NGC 2643 as a non-existent object just south of the east end of the galaxy chain. Instead, it plots IC 2390. SkyTools, however, plots NGC 2643 at the location of IC 2390. The NGC IC list of Wolfgang Steinicke indicates that NGC 2643 is non-existent but that it also may be the same galaxy as IC 2390. I have assumed that it is, basing my observation list on SkyTools.

My observations are

NGC 2624: At 256x a somewhat oval patch of light. NGC 2624 is more clearly visible than NGC 2625.

NGC 2625: At 256x a somewhat oval patch of light. NGC 2624 is more clearly visible than NGC 2625.

NGC 2637: At 256x a very faint glow that was visible about half of the time.

NGC 2643: At 256x a faint, elongated glow.

NGC 2647: At 256x an easily visible oval. Of all galaxies in M 44 I found this one easiest to see.

IC 2388: At 256x almost stellar next to a faint star. Close inspection revealed a faint glow around the galaxy and nothing around the faint star west of the galaxy.

UGC 4526: At 256x visible as a fine needle just north of a faint star.

As always,

"Give it a go and let us know!
Good luck and great viewing!"

From 2015 at 337x, 22"
IC-2388 = Averted vision caught it twice. Makes an equilateral triangle with two stars.
NGC-2624 = A bit easier to see with direct vision. An elongated smudge.
NGC-2643 (aka IC-2390) = Bright core, slightly elongated. Held with direct vision briefly.
NGC-2647 = Less obvious than NGC-2643. Averted vision 3.

I observed these galaxies about 20 years ago with my old 20-inch f/5, but didn't take notes on each one or make a sketch. Just like wvreeven noted, I found them surprisingly difficult to see among the bright stars of M44, and that made it fun challenge.

Quote:

Originally Posted by Howard B

I observed these galaxies about 20 years ago with my old 20-inch f/5, but didn't take notes on each one or make a sketch. Just like wvreeven noted, I found them surprisingly difficult to see among the bright stars of M44, and that made it fun challenge.

Perhaps time for a revisit with your 28" and see if they are a bit easier now?

Yes! All I need is a clear night, something quite rare this winter.

Now I need to do some digging through my old notes. It was over 10 years ago. I’m sure it was with my 12.5” I took on this challenge. I believe I actually did a sketch. Can’t remember how many galaxies I manage. It was a fun chase.

Bill