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by Bruce Jensen
Well, it took awhile to find some time to write it, but finally here are a few notes on observations at Lassen Volcanic National Park, July 15, 16 and 17, 1999.
As most of you already have learned from other reporters, the sky conditions were nearly perfect, a great improvement over last August. The first night I attended, July 15, saw a bit of haze but the darkness was so deep that it compensated amply. The subsequent two nights just got better and better. It reminded my of two nights, long ago, when the sky was ablaze with the light of a million stars and I just stared at it for hours. Those nights were also in this same park, in the eastern backcountry. Then, I had no scope, only my 7mm wide eyes. This time, I could collect 5,000 times more light and resolve features 60 times smaller.
The park itself is sheer joy, day and night. Nature sings her sweetest songs in places like this...and the song is not merely one voice, but a limitless symphony of sensual delight. The ecstatic stimulation is so far removed from the drone of everyday life that to go there is almost like being born into a different set of dimensions with different physical aspects. The head feels clearer, the body feels lighter, the spirit is strengthened and renewed. The brilliance and music of the landscape, the loving breathe of Nature on one's cheek with every breeze, and these coupled with the precious dome of darkness so absent in our everyday lives, make the gentle Lassen wilderness of summer a preview of paradise. Every day spent there is a day added to one's life.
Equipment consisted of an 18" Starmaster dobsonian-mounted reflector, several widefield eyepieces of various description, Uranometria complete volumes, and charts and information gleaned from a variety of sources, mostly the Internet. In the following descriptions, magnitude is usually expressed as "m" followed by the magnitude given from one of several sources I use including the Uranometria Deep Sky Field Guide.
Cool night, slight low haze (up to perhaps 12,000 feet), but quite steady atmosphere and extremely dark; no appreciable light domes in south due to horizon haze.
After looking at the usual preliminary objects including M57, M13, Albireo and Epsilon Lyrae (which, by the way, split fabulously well at full aperture immediately in my 18" scope - who needs mirror cooldown time?), I set myself to check a few objects in Sagittarius, including one that has proven itself to be a good indicator of sky conditions in the past. Barnard's Galaxy, NGC 6822, was relatively easy to spot but not especially detailed at 92x, owing to low elevation and the haze. This would imply poor transparency, but given the low-level haze, this object might not be the best measure of the sky tonight for objectss at greater elevation. Filtration using an Ultrablock filter did not help much on this night. Its close neighbor, NGC 6818, the Little Gem PN, was a tiny, bright blue-green ring at high magnification, and it obviously was in no need of light filtration. Finally, with a quick scan toward the Sagittarius Dwarf Galaxy the field easily identified, but with only a "possible" faint mottling noted, I cannot classify for certain this object as a "bag."
The remainder of the night focused on objects higher overhead, and was far more successful. The Milky Way was by now taking on its most magical glowing appearance, and large dark lanes were beginning to appear with different intensities of "blackness" (the rift in Cygnus just north of Deneb was particularly inky-looking).
Colder, clearer, still relatively steady skies. A truly great night.
After the requisite bright objects and a happy show-and-tell session for some visitors, some faint planetary nebulae became the evening's quarry. Hunting down these ghostly critters was time-consuming, because many lay in either very rich or very poor starfields and in themselves are faint. None of the Abell PNs showed a central star as far as I could tell; they were far too faint for my 18" of aperture.
For a quick rest, I zipped over to M13 in Hercules, tonight at its very best, an unbelievable tangle of star strings that defy description. A perfect widefield view at 225x. I zipped over to Abell 2151, the Hercules Galaxy Cluster, to enjoy the wonderfully rich view of galaxies in that tight grouping. The area is so rich, and Uranometria so large scale, that identifying individual galaxies is tough, but I managed NGCs 6040, 6041 and 6042, the apparent brightest individuals. Next year I'll bring a laptop and charting program, and go to town on galaxies.
After this evening's joyful exercise in eyestrain, I popped onto some bright favorite objects to close out the night at about 2:30, and packed up.
Earlier in the day, Marsha Robinson, Tom Morris and I took a truly splendid 5-mile round trip saunter from King's Creek Meadows to Bumpass Hell on the back route. Longer than the main trail from Bumpass Hell parking, it is also lusher, more forested, and passes an amazing stretch of mountainside meadows, liberally springing with water in the form of streams and large seeps, all interspersed between craggy cliffs of fearsome lava rock. It also passes Cold Boiling Lake, a body of water known for its cool bubbling gases, and in the past for its spectacular 10,000-strong squadron of dragonflies. It is an exquisitely scenic and refreshing way to get to Bumpass Hell if the main trail is closed or if you long for an alternate route. It is also a great warmup for the hydrothermal wonders of Bumpass Hell, where the boiling acidic water from the earth's bowels turns the earth inside out and creates a stark and colorful landscape of oxides and sulfur crystals. The sights, sounds and smells of the roiling water, bubbling mud and escaping steam are unmatched by anything we experience in everyday life, and are enchanting in their own way. Highly recommended, especially with hiking partners as companionable as Marsha and Tom.
The best night of all. Stunningly dark and clear, very stable seeing, Milky Way shadows, and best of all, public visitation. During the night, the TAC group probably hosted around 200 guests (informal estimate), which is a lot for a spot in the wilderness at 8,000 feet and 200 miles from the nearest big city. Hosting guests is truly wonderful, in many ways the best part of skywatching. Sharing these views with people, communicating with them about the beauty and science and philosophy of astronomy, and seeing the hopeful and excited reactions of children of all ages is one of life's greatest rewards.
And, the views were eyepopping. Nothing can compare with viewing the 100 or so brightest and biggest deep sky objects in a pristine sky. We poor souls in the SF Bay Area get the chance to do this so rarely that every opportunity becomes one to relish. That night will remain in my memory for many moons, my friends. The chance to see spiral galaxies in all their grand design glory, the Veil Nebula cascading recklessly cross space and time, and star clusters looking like fireworks on July 4th, and then having the thrill of showing these amazing things to new friends under an infinite sky, is a lifetime experience.
The July 1999 Lassen observing trip, despite its brevity, was the best observing experience of my life. What a wonderful group of friends. What an extraordinary observing location. What a sublime experience.