Backyard Observing with a C90

in Oakland, 1997 Feb 2

I went out with a group of friends to the local dark sky site on Saturday, February 1st. The weather had been cloudy most of the week, but the weather forecast was for clearing skies Saturday afternoon and evening. Needless to say we got clouded out, and after the two hour drive back home, the skies were perfectly clear at my house. Some of my friends decided to go to a local outdoor preserve for some Sunday night observing, but their local spot is an hour away for me. I decided to take my C90, on it's Orion type inexpensive equatorial mount out to the backyard.

I live in Oakland, California, a rather populous city in a major metropolitan area. Light pollution is a big problem, but tonight the neighbors' backyard lights were out, and I was able to see stars down to about mag 4.5.

The C90 is 1000mm at f11. I brought with me a Meade 26 super plossl, an Orion 10.5 MegaVista, a Meade 6.4 super plossl, and an Optica B/C 5 ortho, which gave me 38x, 95x, and 156x, and 200x.

I decided to hunt double stars. I was using Norton's mag 6 star atlas. After viewing M42 for a few minutes, I started hunting for Epsilon Monoceros, described as a "nice yellow and blue pair" in Norton's. It wasn't difficult to find with the puny 5x24 finder. The pair split easily, but I sure was surprised to see diffraction rings! I had never seen this before in the C90. Seeing was exceptional. The colors looked more white and green to me. This is an attractive double.

I then went to Beta Monoceros, described in Norton's as "a magnificent triple! B and C components are 2.8" apart, their images may merge in small scopes when skies are turbulent." Not tonight. I cranked it up to 200x. A nice clean dark lane between the fainter components. The C90 had never performed like this, or maybe I never expected it to perform like this so never gave it the chance.

I jumped over to Castor, in Gemini. This was a very close double. It didn't resolve at 38x, but did at 95x.

The atlas listed Adhara in Canis Major as a double, but said it need at least a 4 inch scope. It is very low on my horizon. I was able to spot it through a tree and figured what the heck. Darned if I wasn't able to split it at 95x.

I was on a roll and noticed Ursa Major rising (this was about 8:10 local time). I decided to find M81 and M82. The sky was brighter here and it was difficult to star hop as there were few stars visible to hop to. I managed to get to the right area (after turning the equatorial mount 90 degrees to make it easier to scan) and found the very faint patch of M81. M82 eluded me, but other than Andromeda, this is the first galaxy I've found from my backyard.

I still had work to do inside, so I took a quick view of M35 in Gemini, and then went back to M42, using the Ultra Block filter. The filter helped with contrast and made M43 more prominent

This was a terrific night in my backyard, and I was very pleased with the way the C90 performed mounted on the small equatorial mount. It was plenty sturdy and is light enough that I am able to pick up the whole thing and move it around my yard.

I encourage everyone to enjoy the night sky and use your backyard. There's plenty to see out there.

Richard Navarrete; last updated: 1997 Feb 2