Oof. I haven’t been posting much. This year has been busy. With the SCA starting up again, a lot of time and emotional energy has been spent on prepping for wars, new classes, competitions, and planning an event I’m running next month. Not much time for astronomy.
However, there has been some recent observing. Details below the fold.
I was able to take my quadrant to Lilies war this year. The weather was pretty awful. Mostly too hot to want to do anything. The evenings were relatively nice early in the week, but since I wasn’t able to do much during the day, I spent most of them being social instead of doing science. As such, very few observations were actually taken in the evening. Rather, a good number of them were of the planetary parade that happened in the early morning that I happened to catch when I woke up to use the restroom. For some reason, I evidently entered the data in the Google sheet I’m using to track observations, but then failed to ever write a blog post about it.
Last night, Saturn was at opposition. Such times are important for the calibration of the planetary models so I made sure to go out and observe. Unfortunately, the night got off to a rough start. First, the quadrant has to be leveled using screws in the corners. To avoid them sinking into soft ground or grinding against cement, I typically place small wood blocks underneath. Everything seemed to be fine until I aligned and was slewing across the sky to take a measurement and one of the screws slipped off the block throwing everything out of level. I had to get it back on the block (not an easy task after the quadrant is fully assembled), relevel, and realign.
Second, I had was that a few observations in, the plumb bob that I use to check the leveling as well as hold the wire taught to take measurements against suddenly fell off. Typically this means the wire broke and isn’t too much of a problem as I keep spare wire in my toolbag I bring. However, this time, the knot of wire simply slipped through the hole in the top of the plumb bob. I was able to get it back through and make the knot a bit larger so things went pretty smoothly.
The next issue was that, shortly after sunset, we hit the dew point. This tends to be a problem because it means my glasses fog extremely easily. As such, I often hold my breath when aligning a star for observation. But when the humidity is really bad, simply putting my face near the quadrant causes them to fog up making observing impossible. Fortunately, the temperature dropped quickly and the humidity settled out and I was able to observe after a short break.
I did a few stars but was mostly there to take several readings of Saturn since it was the real target for the night. However, when getting home and processing the data, things were clearly off. Early observations seem to have their azimuth low by about $0.75º$ while shortly before switching to Saturn, they are suddenly off by $2.25º$. I don’t recall any unexpected shifts in the instrument, but this did force me to make some significant adjustments to the data to account for this.
That being said the adjustment was very consistent. Comparing the individual observations, almost all of them fall within $0.15º$ of the correct value for azimuth once this correction was applied. And that’s not surprising looking at the data. As I was taking the readings, there was very good consistency; the readings were spaced out by almost exactly two minutes each time and the altitude and azimuth were both increasing at about half a degree during each interval. When the data is so consistent like that, it’s typically a sign that the observing is going well, even if there’s an alignment issue which needs to be corrected for later.
Ultimately, after the correction and averaging the results, the error in both RA and Dec both ended up just under $0.1º$ off which is pretty good.
Unfortunately, posting is likely going to be light for the rest of the year. Aside from the event I’m running in a month, I will be attending Great West War a few weeks after that, and then a few weeks after that my girlfriend will be moving here from the East kingdom which I’m preparing for as well.
However, should the weather be nice this weekend (current forecast is partly cloudy), Yseult and I are planning a camping trip in an excellent dark sky site in southern Missouri and are intending to do a lot of observing. So hopefully there will be much to report there!