The Winds of Rho Ophiuchi
Four hours out of Perth, deep in the wheatbelt, the night skies of Lake Brown are the darkest one could hope for. Whilst previously I have visited here for nightscape photography, this time I took my telescope to take advantage of the darkness and the quiet. After an uneventful drive I picked out a nice part of the camping grounds close to the shore and set up my telescope. There was no one around - I was the only traveller to this distant lake.
It was a long way to go and the skies in the evening were lined with thin clouds. The forecast using ClearOutside.com had predicted thin and high cloud, but showed it clearing as twilight became deep night. With a little concern (after all, it was a long way to drive) I watched as, indeed, the clouds drifted to the north-west and thined out to almost nothing.
Game time. My first target was the region around the star of Antares. I was hoping to catch the reddish colour of Antares with the blue of the nearby star ???. Between both stars lies the Antares nebula - partly illuminated by these star's brilliance. I did a two hour run on this target but noticed that for some reason a slight trailing of stars was present in the images. The telescope alignment was accurate, and the tracking computer was locked in on the guide star throughout the process, and yet star trailing was still present. Much later I figured out that I'd forgotten to back-off the guider's control loop - the Skywatcher Synguider will often over compensate if its aggressivness is not backed off a bit.
At midnight I switched to my next target - the Rho Ophiuchi nebula. This is a fainter target and I increased to 10 minute exposures. Another two hour run (tracking was better) I completed the run. I love the play of the nebula being swept by imaginary winds between the shining of the stars of Ophiuchi.
With dawn approaching, I packed up my gear and slept on my car seat before heading home.
