by Peter Natscher
Wednesday night, August 7th, turned out to be another one of those observing nights of superior seeing. There was no incoming fog to cover over the surrounding cities light pollution, and this cut the threshold naked-eye mag.. limit down a bit, to around 6. The sky above 30 degrees from the horizon provided subarc-sec seeing with good transparency, mag. 6+ naked eye in the summer triangle area directly overhead. At 11 pm, the transparency = 6, and the seeing = 7.
On my way to the Peak from Monterey, I did notice a lot of haze in the air, but thought it was the usual marine layer along the coast. Inland, upon driving up the Peak's road from San Juan Bautista, the haze was very noticeable all around, appearing as a thick reddish-brown smoky layer, and obscuring all distant views only a few miles away. Most of the distant mountains, 20-50 mi. away, were not even visible, and the sun had a reddish tint to it's color. It then struck me that the satellite images I've been watching showing the smoke from the Florence Fire, in S. Oregon, was being pushed 400 mi. south into central California. Last night's expected dry transparent air was being smoked up terribly from Oregon's third worst fire ever (the worst forest fire in 130 years).
Watching the sun set from Fremont Peak over a smooth Monterey Bay was gorgeously red due to the heavy smoke extending hundreds of miles out at sea but it was a bit disheartening. I knew that my observations last night would suffer a bit because of the thick fire smoke to the west, and all around. The Park Ranger and I could easily smell the smoke which was traveling from over 400 mi. from the north.
Last night's project was to continue logging and sketching eight Herschel 400 objects that were nearby Spica, in Virgo. These mag. 11 and 12 NGC galaxies were only 20 degrees above the western horizon at 1-1/2 hrs.. after sunset, and the smokiness in that direction made these objects a challenge to see. My well baffled 10 in. Mak-Cass. did a good job keeping the FOV dark enough for me top still see the faint fuzzies as they were setting. I now have 290 H400 objects logged and sketched. I will continue this project up at the Peak again this Saturday night. I'm hoping that the smoke will move out soon so that this weekend's skies will be more transparent.
Did anyone else out observing notice all of the fire smoke in the air last night?
Monterey, California
A-P 10 in. f/14.6 Maksutov-Cassegrain
Herschel 400 Observing and Sketching Project