Mars Recedes

Posted by Josh Walawender on Sat 07 November 2020

A narrow window of opportunity to observe between some bad weather forecasts and a series of nights where I had to work meant that Saturday night was the observing night for me this week. The Moon wouldn't rise until almost midnight, so it was a good time.

I went up the Mauna Loa road despite the web cams showing the clouds up at the 11,000 foot elevation. When I arrived at the end of the road I was still in the clouds and rain though it looked like the clouds did not go much higher. I decided to wait it out. It eventually did clear, but not until about about 8:45 PM.

I hadn't done too much planning of what to observe for this session, so I simply picked an observing list in Sky Safari at random. This particular one I had pulled from an article in the November 2019 issue of Sky and Telescope Magazine.

It turns out the list was intended for a larger telescope than the 6 inch I'd brought. While the first few objects (the NGC 7063 open cluster, a 10th magnitude double star, and the NGC 7013 galaxy) were easy, the next object was an 11.8 magnitude planetary. This would normally not be too difficult, but the planetary was merged with a similar brightness background star which made it challenging to pull out. The final two objects in the list were mag 13.4 and 14.0 planetary nebulae which I did not attempt.

From there I bounced around a bit, jumping across the sky to Almach, the gorgeous double star. The seeing was improving and I was curious to try to resolve the BC components. Almach's AB pair is a glorious sight: a bright color contrast double about 10" separation. The fainter, blue companion is itself a double star of about 0.2-0.5" separation (sources differ). Looking at the B component with the 3mm setting on the 2-4mm Nagler Zoom eyepiece (400x magnification). I could detect elongation in moments of good seeing. My eyeball estimate of the position angle was off by about 25 degrees from the nominal value, so it was not a clear detection.

After stopping at the edge on galaxy near Almach (NGC 891), I went for Mars and spent quite some time with it. As I've mentioned in the previous two entries here, I really don't know my Mars features all that well. I did spend some time with SkySafari and clear identification of Valles Marinaris which was facing Earth prominently at the time.

I also played with colored filters. I'd bought several of them years ago, but rarely used them due to the hassle of installing and removing them on an eyepiece. Earlier this year, I picked up a Theia Filter Changer made by nPAE. It slots in nicely in front of my diagonal on the refractor and makes it easy to change filters. I tried a #81A (a subtle filter which enhances red) and a #41 filter (a deep red). I initially did not think the #81A did much, but on a longer inspection, it did help with some of the dark markings on Mars. The deep red #41 filter was such a dramatic color shift that I found it distracting. It did help enhance dark features, but it was not a pleasing view.

After a long inspection of Mars, I spent a little time hitting well known objects in and around Orion (M42, M78, Flame Nebula, and NGC 1999) which were rising. At this point the Moon was only a few degrees below the horizon, so I packed up a headed home.