I decided last minute to head to the "road 6" observing site, on the central coast, on 24 August. I could fit one quick trip so long as I started driving back at around 4am to get back home and take one of my kids to school after a doctor's appointment. I planned to have around 3.5 hours of observing, (8:30pm to midnight), 3-4 hours of sleep, and then the 3-hour drive home. While places like Lake Sonoma and Fremont Peak were shorter drives, their transparency forecasts were poorer.
This was my first visit to the site, and while the horizons are compromised by trees and hills in multiple directions, it is a large and flat area, peacefully off the main road. There's a decent view due south through a gap in hills to -43 degrees declination, then on up through Polaris, so at least objects can be observed at culmination. After setting up I spent some time clearing the area of loaf-sized rocks which were scattered around, to make the area even more drivable. Once fully dark, my SQML read 21.35 -- not great but around as good as I've had from this area. Around 11pm I noticed the sky quality had dropped, to 21.2, and I noticed some high puffy clouds surrounding Polaris. West and south were still clear, so I continued until midnight. I used my 10-inch f/3.75 Newtonian with a PVS-14 night vision device and an assortment of filters. Here are some highlights:
M16 Obvious pillars of creation, the two opposite the dark nebula intrusion which points at them -- along with a finger-like pillar to one side. The nebula was like a shell, the obvious effect of stellar winds blowing gaseous material away. I traced the wisps of nebula which surround the brightest part to other nearby nebula and was reminded of how connected they all are -- the bright objects like the Eagle, Swan, Lagoon, etc. are simply more visible because stars illuminate them more. I can't find a good image to show this interconnectedness -- the following, from the MDW Sky Survey, shows the nebula brighter than what I saw, but hopefully conveys what I mean.
Sh2-12 / NGC 6383 Bright star with a small associated cluster, surrounded by very faint, large, mottled round nebula, larger than the field so I needed to pan around to its irregular edges, nibbled with dark nebula. Just off the side from it is M6 the butterfly cluster, which when I center in the field, I can see the outer arc of this nebulous sphere.
NGC 6357 Very small intense elongation in the center of a very nebulous field., with many wisps and knots surrounding it, streaked with dark nebula, speckled with spheres, and wisps trailing from it in all directions.
NGC 6302 Bug Nebula. I can see it unfiltered, but it completely disappears with the 685 longpass filter, best view TriBand filter. Though at small scale, I can see the two ansae, one longer than the other.
M57: Bright and round. Due to small scale, I didn't look for detail. But in a 2-degree field, the goal was not to see particulars of the nebula, it was to see it floating in the myriad of stars the night vision device reveals.
I woke at 3am after a too-short nap in my car and got out to stretch. Looking up, I could see M31 in between puffs of cloud. And then I heard the soft leathery flaps of bat wings and looked up to see a very large bat 10 feet above me, quietly making its rounds. Starting the drive home, listened to Heinrich Ignaz Franz Biber's "The Rosary Sonatas," also called "The Mystery Sonatas." I bought the CDs from Half Price Books out of curiosity a few weeks ago, not knowing anything about the music, and left them in my car. I was shocked by their beauty and the virtuosity of the playing. Biber wrote in the late 1600s, and in parts the sonatas sounded like the honed results of his improvisations on the violin. He was the Jimi Hendrix of his era, finding new sounds and possibilities with his instrument. Travelling through the tunnel of light formed by my headlights, I saw a frog hopping across the road, a few mice, a young bobcat zigzag in front of me.
I don't know if it was my exhaustion, the exhilaration of seeing things in the sky very few humans even know about, or the transcendence of the music, but I was in a mystical state of mind. Starting on the main road, I felt my tunnel of light was leading me through a sort of hell, at least an astronomer's hell, complete with vapors and fiery lights. Few of us travel to our observing sites at night, so it was disturbing to see why the sky quality is not as good as the light pollution map would promise, and why we resort to ever larger aperture telescopes or technology (astrophotography, night vision) to enjoy this hobby. The nearby military base casts its own light dome. Individual farms blaze with security lights on sheds and barns. The haze of fog in the Salinas Valley diffuses the light into the sky, rather than blanketing it like a marine layer. I noticed a pillar of light, like something from the Bible, forming an awful vertical rainbow miles ahead of me before reaching the source: nighttime pickers at their hard labor, following behind the brightly lit sorting machine and tractor. Multiple buildings along 101 have bright unshielded lights pointed up. One large multistory building under construction had around 10 floors framed but lacked outer walls. The entire inside was brightly lit up -- I presume for nighttime construction crews -- it was bright enough to light the interior of my car though it was a quarter mile away, and it formed a sickly glow in the sky above. One winery had its tank and pump system completely lit up. I think north of San Francisco is not being developed so much, so places like Lake Sonoma is getting to be darker than sites south -- unfortunately north typically have worse transparency. In any case, it does not bode well.
Fortunately, the 2 CDs worth of Biber's music carried me home safely.
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