Hemisphere:  Northern  ·  Constellation: Ursa Major (UMa)  ·  Contains:  M 109  ·  NGC 3992
Getting plate-solving status, please wait...
M109 Barred Spiral Galaxy, 


            Jerry Macon
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M109 Barred Spiral Galaxy

Getting plate-solving status, please wait...
M109 Barred Spiral Galaxy, 


            Jerry Macon
Powered byPixInsight

M109 Barred Spiral Galaxy

Imaging telescopes or lenses: PlaneWave Instruments CDK14

Imaging cameras: ZWO ASI6200MM-PRO

Mounts: Paramount MEII with Absolute Encoders

Guiding telescopes or lenses: PlaneWave Instruments CDK14

Guiding cameras: Starlight Xpress Lodestar X2 Mono

Software: Nighttime Imaging ‘N’ Astronomy N.I.N.A.  ·  PixInsight 1.8  ·  StarNet++ .

Filters: Chroma 3nm Oiii 50mm  ·  Antlia RGB 50mm  ·  Antlia Ha 3nm 50mm

Dates:May 6, 2021

Antlia L 50mm: 33x200" (1h 50') (gain: 100.00) -15C bin 1x1
Antlia RGB 50mm: 42x200" (2h 20') (gain: 100.00) -15C bin 1x1

Integration: 4h 10'

Avg. Moon age: 24.73 days

Avg. Moon phase: 23.93%

Bortle Dark-Sky Scale: 3.00

Temperature: 8.00

RA center: 11h57m35s.420

DEC center: +53°2216.76

Pixel scale: 0.538 arcsec/pixel

Orientation: 90.651 degrees

Field radius: 0.377 degrees

WCS transformation: thin plate spline

More info:Open 

Resolution: 4144x2876

Locations: Dark Star Observatory, Taos, New Mexico, United States

Data source: Own remote observatory

Remote source: Non-commercial independent facility


This is a second go at this lovely target to see if longer exposures give me a better image, using the same scope/camera. The earlier version used exposures of 40 seconds for RGB and 80 seconds of L. This one is RGB and L both 200. Up to 5 times longer. Almost twice the total exposure. And the processing uses more conventional colors, the earlier one a very different color balance. I think this one is much better. I am not at all happy with the processing I did one the earlier one, will need to redo it.

Galaxies anyone?

A really nice collection of galaxies, besides NGC3992.


Messier 109 (also known as NGC 3992) is a barred spiral galaxy exhibiting a weak inner ring structure around the central bar approximately 83.5 ± 24 million light-years away in the northern constellation Ursa Major. M109 can be seen south-east of the star Phecda (? UMa, Gamma Ursa Majoris).

Messier 109 was discovered by Pierre Méchain in 1781. Two years later Charles Messier catalogued the object, as an appended object to his publication.

Between the 1920s through the 1950s, it was considered that Messier objects over 103 were not official, but later the additions, further referred target objects from Méchain, became more widely accepted. David H. Levy mentions the modern 110 object catalog while Sir Patrick Moore places the limit at 104 objects but has M105 to 109 listed as addenda. By the late 1970s all 110 objects are commonly used among astronomers and remain so.

In March 1956 came M109's sole event-observed supernova, 1956A. It was a type Ia supernova in the south-east part of the galaxy, glowing at magnitude 12.8, reaching 12.3 at its maximum.

This galaxy by far the most distant object in the Messier Catalog, followed by M91.

M109 has three satellite galaxies (UGC 6923, UGC 6940 and UGC 6969) and possibly more. Detailed hydrogen line observations have been obtained from M109 and its satellites. M109's H I (H one) distribution is regular with a low-level radial extension outside the stellar disc, while in the bar is a central H I hole in the gas distribution. Possibly the gas has been transported inwards by the bar, and because of the emptiness of the hole no large accretion events can have happened in the recent past.

M109 is the brightest galaxy in the M109 Group, a large group of galaxies in the constellation Ursa Major that may number over 50.


Sky plot

Sky plot


M109 Barred Spiral Galaxy, 


            Jerry Macon