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Cosmic Challenge: M109

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#1 PhilH


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Posted 01 May 2018 - 05:23 AM

Messier did not live to see a second edition of his catalog, but objects 104 through 110 have been added posthumously by others. M109 joined the ranks in 1953, when astronomy historian Owen Gingerich noted Messier's observations of six additional "Méchain objects," now known as M104 through M109.

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#2 Astro Canuck

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Posted 01 May 2018 - 07:41 AM

 In July 2012 from my old location and after 13 years I finally saw all the Messier objects with

my C8 from Halifax, and it's light pollution.  M109 was a real challenge, heck M76 was easier as was M97!   I used my 25mm TAL Plossl (80x) eyepiece and kept Phedca just out of the field,

I used adverted vision also had a dark cloth over my head to block other lights about and taped

the telescope a bit.  I was lucky to have a rare clear night here and Ursa Major overhead, but

there it was, a faint smudge in the eyepiece. I took a deep breath, looked away and then back

into the eyepiece, it was still in the same spot. It was to me just a faint grey smudge, never

saw any elongation. I stayed with 80x as it gave a slightly better darker background for me,

anything higher it was lost and in my 40mm Plossl (50x) it made the area too bright. 

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    Fly Me to the Moon

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Posted 01 May 2018 - 01:23 PM

Méchain was really talented at discovering the subtle stuff. If we were to port back to that era... I'll bet we would be frustrated with the equipment (coatings, eyepieces, ergonomics)... but probably Astounded at the sky darkness... even from "populated" sites.  Tom

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#4 parebal0


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Posted 06 May 2018 - 12:45 PM

Thanks for this months challege Phil!  Great write up and informative narrative about this deep sky wonder.  Going back over my SS notes, I’ve viewed M109, 3 times this year, with my Evo 9.25, 13mm Ethos.  Twice from my home Bortle 7.0 sky’s and once from a somewhat dark sky site.  I noted it as relatively difficult from my home location, and could see the 13.2 mag star located near its center.   Local star of course!  crazy.gif  I also noted NGC3953, as easy to observe when compared to M109.  I also use M109 as a reference object for my home transparency, as it can vary so much during a night of observing.  


Very nice that you could observe it, and sketch such a fine drawing, with your 4 inch refractor!   Clear sky’s.....Peter A.

#5 Jon Isaacs

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Posted 08 May 2018 - 04:39 PM



Thanks once again for your cosmic challenge.  I was able to see m109 in my 80 mm F/6 at 24x , i saw the glow of the body.  At 50x i saw a bit more .  


The area around Phecda is one of my favorites and there some interesting groupings in a large scope. 



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#6 russell23


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Posted 16 May 2018 - 08:33 PM

M109 (NGC3992) is classified as an SBbcI-II spiral and is one of the closest galaxies in combined size an structure to the Milky Way.  The mass, rotational velocity, and radius are very close between the two galaxies.  In addition, NGC 3992 is a multi-armed barred spiral like the Milky Way. 

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