#1  
Old 13-06-2018, 12:11 PM
Tropo-Bob (Bob)
Registered User

Tropo-Bob is offline
 
Join Date: Sep 2013
Location: Cairns
Posts: 1,584
Messiers in Ursa Major-Then & now. (& Mallas)

Many years ago, I purchased "The Messier Album-An Observer's Handbook" by Mallas and Kreimer. In the back, there was a back section to take notes, so I did. I set out to observe all the Messier object and completed this mostly in a year, but there were a few difficult objects, notably in Ursa Major that took me additional time to find.

Unfortunately, I have not been a great note taker over the years, and those I took, (except above), I threw out in a space-saving cleanup a few years ago. Nevertheless, I thought it would be good to do some current observations, compare that with my general memory over the years and my specific notes from the early 1980s.

Two evenings ago (June 11th), I went bush with my Vixen 140mm so I will use these as my current (now) observations. Back in the 1980s, I had a 8" EQ, Astro-Optical telescope, where my low power EP was a Kellner 25mm (56x) with a apparent field of 37 degrees. Also, most of these observations were from a suburban location.

I have general memories of some Messier objects from my time when I owned a 12.5" Dob. I will mention these when I can.

Furthermore, I have included some of the descriptions that Mallas made in his Observer's Handbook.


M97- Planetary; The Owl Nebula. (I have heard this described as the most difficult M object to see.)

Then (8"): 1st May, 1981. Could not see it. Had the right position
27th March, 1982 Similar to M1 but fainter. Hard to see.

General memory (12"): I recall this as being large, diffuse, circular and faint. I was always glad to find it, as it was never easy.

Now (140mm). June 11th. This stood out much more brightly than I expected. The Owl Nebula was easy to see. It reminded me of seeing a plate, face-on from a distance. Using 33x & 62x, I could see no variation in brightness across this circular nebula (Thus, it looked like a plate, and I did not notice the Owl's dark eyes!)

Mallas: At 120x in a 4-inch refractor...M97 appears as a rather large gray oval. It is practically featureless.



M101- Galaxy.

Then: 1st May, 1981. Could not see.
26th Apr, 1982. Large, faint, circular, featureless mass.

I have no general memory of this.

Now: A large, face-on galaxy that was seen reasonably well. However, it seemed to extend in a rather, diffuse and uneven way.

Mallas:A beautiful object...Low powers are best. The clearly seen central region has a fluffy texture and a silvery hue. Surrounding this ares is a soft sheen containing some nebulous patches.



M108 - Galaxy

Then: 1st May, 1981. Could not find.
26th Apr,1982. Edgewise. Faint with hint of a triple center.

Now: A edge-on galaxy, that was bright, but small and was somewhat odd shaped. Its seemed to be broader at one end and also was not uniform in brightness.

Mallas: A silver-white beauty for small telescopes, saucer-shaped and fairly well defined. The central region is quite bright and irregular, surrounded by light and dark nodules.



M109.

22nd May, 1981. Could not find.
26th April, 1982. Medium size and faint. No center seen.

Now: Small and somewhat like a loose globular. Appeared to have faint, almost star-like points in it.

Mallas: A splendid galaxy for small apertures, though only the brighter central region can be seen. It is pear-shaped, with a strong suspicion of granular texture..



M81.

May 83. Faint round blob-very difficult. Finder stars confirmed identity.

General Memory: I have seen this from bush locations using both 12" & 8" dobs. It only reaches about 4 degress above the horizon. It appeared as round, but no other details were noticed.

Now: The horizon had a few small objects in the way and in any case, it may have been slightly too late in the year to see this at maximum altitude.

Mallas: In the 4-inch refractor, a beautiful object! ... M81 has the most strongly granular central region of almost any galaxy. The outer parts are motted and uneven in brightness and texture ...



M82.

May 83. Could not find.
16th April 1985. (Using my then new, wide-field (65 degrees) EP at 44x). Very difficult faint object-when glimpsed, position was more correct than (imagined in) my mind map. Thus conformation.
(This was obviously a good moment for me. After years of trying to find this, I had done a special trip out to a dark beach at night to have a flat sea horizon. When I saw M82, it was extremely faint and I was not sure. However, the edge-on galaxy was pointing in a different direction than I expected. When, I viewed a star atlas, the unexpected direction was correct, therefore, I had confirmation.)

General Memory: Again, I have seen this from bush locations using both 12" & 8" dobs. It is lower, fainter and more difficult than M81, but can be seen from a bush location without being overly difficult when it is near its maximum altitude. It looks like a streak, which compares strongly with the circular appearance of M81. They both easily fit together in a low-power field of view.

Mallas: A gem! In a low-power field, it forms a beautiful pair with M82. In shape and color M82 is a silver silver, with its brightest part off-center...



FEEL FREE to add you observations: especially if U are from the Northern Hemisphere.

Last edited by Tropo-Bob; 13-06-2018 at 06:34 PM.
Reply With Quote
  #2  
Old 13-06-2018, 12:54 PM
Tinderboxsky's Avatar
Tinderboxsky (Steve)
I can see clearly now ...

Tinderboxsky is offline
 
Join Date: Feb 2012
Location: Kingston TAS
Posts: 1,031
Excellent report and an enjoyable read Bob.
They were like "over the horizon" observations for me.

Last edited by Tinderboxsky; 13-06-2018 at 12:55 PM. Reason: Correction
Reply With Quote
  #3  
Old 14-06-2018, 09:27 PM
gaseous's Avatar
gaseous (Patrick)
Registered User

gaseous is offline
 
Join Date: May 2016
Location: Brisbane
Posts: 782
Nice report Bob - 1981 sounds like a frustrating year for capturing faint fuzzies. I'm always intrigued how published books wax lyrical over objects that seem a little "ho-hum" to people like myself.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 01:18 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
Bintel
Advertisement