Cookie consent

AstroBin saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing AstroBin without changing the browser settings, you grant us permission to store that information on your device.

I agree
Contains:  NGC 3729, NGC 3718
Getting plate-solving status, please wait...

Arp 214 (NGC 3718) - A Beautiful Unusual Galaxy in the Big Dipper

Technical card

Resolution: 5232x5232

Dates:May 4, 2019May 23, 2019May 27, 2019

Astrodon B Tru-Balance E-Series Gen 2: 25x1200" -25C bin 1x1
Astrodon G Tru-Balance E-Series Gen 2: 21x1200" -25C bin 1x1
Astrodon Red Tru-Balance E-Series Gen 2: 31x1200" -25C bin 1x1

Integration: 25.7 hours

Darks: ~17

Flats: ~17

Bias: ~20

Avg. Moon age: 23.74 days

Avg. Moon phase: 40.41%

Mean SQM: 21.43

Mean FWHM: 2.00

Temperature: 12.00 job: 2723010

RA center: 173.251 degrees

DEC center: 53.066 degrees

Pixel scale: 0.239 arcsec/pixel

Orientation: 179.812 degrees

Field radius: 0.246 degrees

Locations: Deep Sky West, Rowe, NM, United States

Data source: Own remote observatory

Remote source: DeepSkyWest


Located in the constellation of Ursa Major at a distance of about 48 Mly (+/- 8 Mly,) NGC 3718 is a warped spiral galaxy with two extended arms that are distorted by the gravitational interaction with NGC 3729, a spiral galaxy that sits only 150,000 ly away (to the right.) The outer regions of the two spiral arms are littered with young, hot blue stars. Hickson group 56 is a group of five interacting galaxies that can be seen above NGC 3718 located at a distance of 400 Mly. NGC 3718 is moderately large object with an apparent magnitude of about 11 with very low brightness outer regions, which makes it a challenging object to image. It requires long exposure times and careful processing to bring out details.

I started this project last month under pretty steady skies. Unfortunately the cooperative weather didn't last long and I had to gather about three times as much data than I actually used to cull out sufficient quality subs. I would have liked to grab at least another 10 hours of data but I've run out of both good weather and time as this region of the sky sinks into the west. My scope hasn't been serviced since last October so I'm pretty sure that the front corrector plat is absolutely filthy. All that dirt may be contributing to the low level light scattering that I see around bright stars. I hope to get out to the observatory to service the scope this next week so we'll see if it helps to clean up the optics going forward. I couldn't gather as much data as I wanted so I really struggled to get this data set processed to my satisfaction. Bringing out the faint arms created a conflict with noise reduction and I had to take numerous runs at the data before I reached a point where I was mostly satisfied with the result. Still I never abandon a processing project without feeling like I could have done better so feel free to give me feedback. Hopefully, I haven't screwed it up too badly. I'll have to revisit this galaxy next year to see if I can get more data.




John Hayes

Sky plot

Sky plot


Arp 214 (NGC 3718) - A Beautiful Unusual Galaxy in the Big Dipper, 


            John Hayes

In these public groups

Cloudy Nights