New Image: Galaxy Double-Double: Holmberg 218 and Arp 270 (NGC 3424/3430 and NGC 3395/3396)

[jthommes]

Here is a galaxy double-double; Holmberg 218 pair on the left, Arp 270 pair on the right. All these galaxies are in the same distance range - about 82 to 89 million light years (by redshift estimate). As such, this foursome are also members of other four galaxy groups - one of those is the Mahtessian 98 galaxy group (also in Temple et al. 2MASS redshift data galaxy groupings - 2016 and 2018 publications).

Other galaxies in this field of note are NGC 3413 and IC 2608. This field also has many background galaxies that are visible in the full size image. Finally, there are a number of visible quasars in this image - the furthest has a redshift of 3.304 and a light travel time (Lookback) of 11.77 billion years.

The image below is a crop of NGC 3424/3430 from the full field - it links to the main page with image and additional information. There is also a link below to the full FOV and annotated image. The full resolution image has a horizontal FOV of 0.668 degrees and an image scale of about 0.58 "/pixel.

I accidentally took a number of 1x1 bin Lum exposures (normally, people with the ASI294 camera take 2x2 bin). The rest of my exposures were 2x2 bin. Since I had the 1x1 bin Lum data anyway, I integrated the Lum stack with these sub-frames as well - they actually provided a little better results than without them.

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  NGC 3430 Crop - Link to Image Page

Full FOV image (Pan and Zoom):
Mahtessian 98 Region(Sh2-221)

Annotated Image (Pan and Zoom):
Mahtessian 98 Region Annotated

Images also available on astrobin -Mahtessian 98 Region

Scope: Celestron 9.25 Edge HD 235 mm at f/7
Camera: ASI294MM (Baader LRGB Filters)
Location: DAA Observatory, Shelter Valley, CA

[starfield]

Nice double feature, Jim. Like the detail you got in NGC 3924 . And the Arp 270 pair is really interesting. It looks like quite a galactic mash up.

[StarHugger]

Wow Jim alot to take in there from close galactic pairs to NGC 3395 & 96, all well annotated too...

Reminds me of Universal Sandbox or similar.

I'll admit I screengrabbed and zoomed in some more.

Thanks for sharing it all.

[MariusD69]

Amazing image! Great work, Jim!

[messier 111]

superb image , thx .

[jthommes]

Nice double feature, Jim. Like the detail you got in NGC 3924 . And the Arp 270 pair is really interesting. It looks like quite a galactic mash up.

Thanks Steve!. I was pleased with the detail in both pairs. I have been wondering if the Arp 270 galaxies are actually in contact or if they are a few light years apart and we only see them together in line of sight.

[jthommes]

Amazing image! Great work, Jim!

Thanks for the kind words Marius! I appreciate them.

[jthommes]

superb image , thx .

Thanks for your comment Jean-Yves! Much appreciated.

[Ylem]

Wow! That's amazing Jim!

[jthommes]

Wow! That's amazing Jim!

Thanks for your comment Jeff! I appreciate it.

[Pavebo]

Congratulation Jim! The picture is really very nice done!

Best regards

Pavel

[jthommes]

Congratulation Jim! The picture is really very nice done!

Best regards

Pavel

Thanks for your comment Pavel! I appreciate it.

[AstroBee]

Really nice image, Jim. It's always nice to see the annotated image too but my preference is to look at the full resolution image on Astrobin and "fly around" looking at all the tiny background galaxies.

[jthommes]

Really nice image, Jim. It's always nice to see the annotated image too but my preference is to look at the full resolution image on Astrobin and "fly around" looking at all the tiny background galaxies.

Thanks for your comment Greg! I appreciate it.

FYI, IMHO, I think it is easier and more effective to view the full size images on my website (annotated and plain un-annotated) rather than astrobin full size for "flying around." Pan and zoom is convenient and easy on both images. For the full immersive experience, you can go to full screen on the pan and zoom by clicking the right most button in the button grouping on the left.

Full FOV image (Pan and Zoom):
Mahtessian 98 Region(Sh2-221)

Annotated Image (Pan and Zoom):
Mahtessian 98 Region Annotated

Annotated Image (Pan and Zoom):
Mahtessian 98 Region Annotated

[Gordon]

Congratulations Jim on having your image selected as our TSS APOD!

app.php/article/4-1-2024-tss-astrophoto ... of-the-day

[Ylem]

Congratulations on the well deserved APOD Jim!

[Juno16]

Outstanding Image Jim!

Saw this image on Astrobin.

You are certainly a master at pulling in great to tail on these distant beauties!

[jthommes]

Gordon,
Thanks for the APOD.

Jeff, Jim,
Thanks for the APOD congrats.

Jim, Thanks for your comment! I have found that I am better off doing a 2x Drizzle in PixInsight and living with reasonable noise rather than no drizzle and Mure Denoise. (Mure Denoise must be used on a native linear stack and cannot be used on a drizzled linear stack effectively.) The 2x drizzle really helps on those tiny objects (relative to full field and native resolution).