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One of those rare, mild evenings with a clear sky and no wind. Venus, Jupiter and the half Moon lay in ascending order. I decided not to try any photography this evening. I would concentrate on viewing these bright objects with my own eyes at the eyepiece. After putting the 6" F:8 Celestron refractor on the MkIV I ran the mains extension lead out to the pier. Then switched on the VFO power supply.
I started with Venus. Which was sinking fast in the low South West. Towards the local trees. I found it very bright and very colourful indeed. Adding filters did not help much. It was showing a half phase with a slightly ragged terminator. Perhaps the wavy edge was just an illusion? As it still wasn't a very rewarding sight I moved onto Jupiter.
Jupiter was higher and further south. Showing two clear belts with one moon rapidly closing on the limb. I was using 120x and 160x, with 10mm and 7.5mm Meade Plossls. Then the 15mm with a 2x Barlow lens.
Over the course of the first half hour this tiny moon slowly disappeared. The view was not clear enough to decide whether it had gone behind Jupiter or was lost in a lack of contrast in front of it. It seemed as if it had gone behind the planet because it had appeared to pass through the end of the major belt. So might have still have been visible against this darker belt. If indeed it was in front of the planet. No matter how I stared I could not resolve any other detail on the planet. Even the belts were not very clear. At this point I was called in for dinner.
Heavy dew had descended on the telescope and mounting by the time I returned outside. I had previously fitted the long plastic dewshield extension so the objective had remained clear. Though it did look quite water marked. I wiped the eye lens with a microfibre cloth and continued by observing the half Moon. Which was very high up to the South above the house. A small wisp of smoke from the chimney was being carried gently east. Plato was well placed near the terminator but I could see no craters in the dark floor.
The long shadows of tall peaks on the crater floor slowly changed over the time I was observing. There were also some brightly lit peaks well out in the darkness beyond the terminator. I tried 120x, 160 x and 240x (using the 2 x Barlow lens) 120x looked reasonably sharp but I could see no more detail at 160x or higher. There were some slight thermal effects. Only an occasional slight shake. I could not say that it was a great night for clarity or sharpness.
Then streaks of thin, high cloud began to move slowly across the sky from the west. The clouds spread out more and more over time. I moved between Jupiter and the Moon and back again depending on which was most clear. It was as if a milky veil had been drawn across the object when cloud intervened. Transparency was very poor through the cloud. Sometimes cloud can be used as a neutral density filter but this high stuff was different. It obscured without light reduction. Probably high ice clouds.
Then I noticed Mars shining redly right through the tall hedge to the east. At first it was too low to get a clear shot. Silhouetted branches were clearly visible through the focuser when I removed the eyepiece.
So I was forced to drag the massive pier away from the hedge to try and get a clear view above it. Finally, I was rewarded by seeing a clear, white polar cap. Rather oddly, Mars accepted 160x better than 120x. Though it was far from detailed at such a low altitude. Pushing the power up to 240 x with the Barlow didn't help. So I continued to stare at it with 160x. There seemed to be a slanting, fuzzy, dark bar across the opposite pole from the white cap but I couldn't be certain.
I seem to be suffering from a bout of floaters recently. Many small dark spots as well as the usual translucent "amoeba". I can see these small floaters all the time in daylight when out cycling. My sight still seems to be normal enough otherwise.
Eventually, even Mars was obscured by cloud. So I packed everything away. I did have a final quick peek at a very poorly defined Orion Nebula. Everything was dripping wet from the dew. I'm now using a 5 diode bicycle rear light at the telescope to peer into my eyepiece box. It was hardly necessary in this bright moonlight and I wasn't observing dim, deep sky objects anyway. So id not need to preserve my dark adaptation. The view of the Moon through the telescope was bright enough to undo any dark adaptation anyway.
Venus was still brightly visible through the larch trees and almost on the horizon. Jupiter already touching the tree tops. The sky showing large banks of thin cloud with a few tempting holes. A pleasant, if not particularly rewarding evening. With an unusual variety of interesting objects to study. Albeit without any great clarity. The last two days have been nearly record level mild. Though not locally. It just reached 50F this afternoon. 55F elsewhere in Denmark.
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