Henry W. Coe State Park Star Party, November 22, 2003

by Peter Natscher


It was a nice star party in the overflow parking lot at Henry W. Coe State Park last Saturday night, Nov. 22nd. The social activity between around 50 avid observers transcended any thought of the cold temperature and the stubbornly poor seeing above. I was prepared to observe in sub-freezing temps. but it wasn't all that bad at my lowest reading of 36F (9-11pm). The low RH (35%) and lack of wind helped keep things ok with me, though. Higher air moisture (high RH, >85%) is the effecting element with regards to temperature comfort. I counted 35 vehicles parked in four rows (by 7 pm) in the overflow parking lot, from the entrance to all the way down to the big tree at the south end. This grand assemblage of astro-naughts and their transportable photon collectors reminded me of days gone by at our other suburban observing sites. I mention 'suburban' because it was indeed a suburban seeing night at Coe. The Milky Way stretched across us above was barely noticeable. So goes the benefits of our suburban living.

Apart from the totally enjoyable smoozing for six hours in 26 'dryer than my garage in Monterey' air, the seeing was pretty soft (2-3 arc-sec much of the time in my 20" Dob's eyepiece. We also had with too much light pollution from San Jose, Morgan Hill, and Gilroy which was exasperated from haze in the area. Epsilon Lyrae went from barely resolvable to not at all and I only occasionally saw the E ad F stars in the Trapezium. That's pretty bad for a good 20" well-collimated Dob. The seeing softness and sky brightness kept me at 300X and below observing only the brighter galaxies, star clusters, and emission nebs. with a UHC and Deep Sky filters. Planetary nebulas' ring details were also blurred. The lower in the sky I observed, the softer the seeing got. I stayed mostly with observing overhead in Pegasus, Andromeda, Perseus, Cassiopeia, and Cepheus. My observational surprise came watching comet Encke lying just west of Sagitta and the "Coat Hangar" asterism with neighbor TACO Bruce Jensen (who we haven't seen in a long time). We watched the comet long enough to see its movement passing by two brighter stars in an eyepiece FOV along with it's slight nucleus and short fan-shaped tail. Using a Lumicon Swan filter (a narrow-band filter for cometary gases) showed the comet with a higher contrast. Raising the magnification to 300X also improved contrast on the comet's nucleus area. Because of its stubby shape, looks like comet Encke's trajectory is in line with the Earth.

I didn't expect diffraction limited results with my new 20" Starmaster last night, but pleeeese, there were the sudden sporadic zephyr wind blasts upon us from the usual west slope (what Coe is famous for) and a haziness that brightened the overall sky darkness noticeably. Rashad--I thought when you escaped into your van, you were busy presenting a sacrifice to the wind god. I now need to vacuum my Starmaster's rocker box and upper tube housing to clean up the parking lot dust clinging to them. Did anyone do a threshold star mag. count last night? I used many of my narrow-band eyepiece filters last night to battle the poor darkness we had. Use of a Lumicon H-B Filter did show me the Horse Head in Orion, and a Lumicon Ultra-High Contrast filter showed other emission nebs. fairly well that were otherwise lost in the gray eyepiece FOV. I'm thinking that the haze was the product of wood-burning fireplaces over a wide area near Coe State Park and not moisture because we had a low RH of 35% @ 36F much of the night. We were warmer up at Coe than those in the area 1,00 ft. below us at Anderson Reservoir. My vehicle's temp. reading sank to 30F as I rolled by the reservoir at 12am on my way out.