4 April 2026 - More Messier and failed GEM setup


I have been disappointed with views of the planets in my C8 SCT ( Celestron 8" Schmidt Cassegrain Telescope). I am not seeing the level of detail it should provide. On Jupiter I can regularly see the North and South Equatorial Bands, but no detail in them and only occasional hints of other bands. There are several potential reasons for this, especially sky conditions. I live in a mountain valley between two significant mountain ranges. The highest range, the Bitterroots,  are just west of me and very rugged. This means there can be significant disturbances to the airflow above me affecting seeing. To test this out I wanted to set up my old 4.5" Newtonian Reflector on a German Equatorial Mount (GEM, or just "equatorial", for short). I had not used it in several years. This telescope is old enough that it uses 0.965" eyepieces. Over 20 years ago I remember using it in alt-az mode and seeing the Great Red Spot and more detail than I am getting now with the SCT. The caveat is that that observation was under darker skies and not in a mountain valley with the air disturbance.
 
Getting the Newtonian set up on the mount reminded me of why I had almost  given up on astronomy for some time. The mount would not hold position no matter what I did. I did a rough polar alignment And using a 20mm Kellner .965 eyepiece was finally able to get Jupiter in the FOV (Field of view). I had trouble keeping it there and was only able to see the two main bands and the moons. I had trouble focusing the scope. Jupiter was only a little past zenith, which made it almost impossible to use the little finder scope or sight along the tube accurately. I changed to the 6.5mm Kellner, but was unable to reacquire Jupiter. I need to spend time just working with this mount and scope before I try this again! At about 22:36 MDT I gave up on it and moved back to the C8SE. I could make out the two main bands. Using the 8mm Plossl (256x) I could also barely make out some knotting in them. Focus kept bouncing in and out. In the 13 mm (156x) the view was much steadier.



At about 22:50MDT I did a Skyalign and decided to try to observe M90 in Virgo . I could make out a small smudge with a smaller one next to it. That didn't seem right. Oops!. I had punched in M60 instead of M90! I reentered M90 and got it. M89 was just out of the FOV. M90 is a spiral galaxy about 58.7 million light years away and contains about 1 trillion stars. The core was noticeably brighter than the rest of it. No other real detail was visible. As I sketched it, the sky was getting brighter as Moon glow became very apparent over the Sapphire Mountains to the east.
 
Shifted to M89 at 23:15MDT.  This is an elliptical galaxy about 50 million light years away and spans 80,000 light years. It showed a bright core. I tried the 13mm eyepiece to try for more detail but it didn't add any detail and just seemed dimmer. I sketched it. I then moved on to M87 and sketched it. This is another galaxy in the Virgo cluster and is about 53.5 million light years away. There was a very faint companion in the FOV. Looking in Stellarium later, I believe it to be NGC 4478. NGC 4476 is slightly smaller and further away. .4476 was probably also in the field of view but under the brightening sky probably not visible.
 
From there I shifted to M86. M84 is in the same FOV. M86 has a brighter core, M84s is slightly more diffuse. After observing for a few minutes I was able to make out a slightly brighter view of the core of M84. I double checked location be using the GoTo function to go to M84 and verify the same FOV. The GoTo has been putting objects barely out of the 25mm FOV to the right. 
 
I shifted toNGC 4438 and NGC 4435. I can slew just a little and bring M86 into the FOV as well as NGC 4461. I can literally watch these fade as the Moon rises and washes them out. By 23:44 objects were so dim that I started shutting down. 
 
M84,M86, NGC 4435 and 4438 are part of Markarians Chain. 
 
Seeing tonight was probably Antoniadi 2-3. Transparency about 4/10. Moon glow got worse a because of moisture and some smoke in the air. When I started Nelm was probably 3.5-4. I could just barely make out all seven stars in the Little Dipper.
 





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