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by Randy Muller
On Wednesday, August 11, I left home for the clear and dark skies of Lassen Volcanic National Park, site of the Alan Nelms Memorial Star Party organized by The Astronomy Connection. Alan was an avid TAC observer and friend of TAC who died suddenly last year.
This was the second and final Lassen star party of the summer, and after an abbreviated trip last month, I was ready to spend 4 nights drinking fully and deeply of the intoxicating astronomical delights lurking in the black skies of Lassen, which delights are mostly invisible from my backyard.
The complete loss of the dark sky is one of the unnecessary sacrifices modern humankind has chosen to make to enjoy a civilized leisurely life. Inhabitants of the cities and suburbs of California must now drive a minimum of 2 or 3 hours to reach mostly dark sites.
Even Lassen, 4 hours (by the fastest route) from my home in Roseville, CA, is plagued by a small amount of light pollution from Sacramento and Chico.
The weather did not look promising when I left. In fact, the night before, I decided to delay my trip by one day, to give the weather a chance to clear a bit. When Wednesday morning arrived, the weather reports were a little better, so I went.
I figured that even if the observing was a total washout, the beautiful setting of Lassen would be more than enough to occupy and delight my senses.
There was lots of high cirrus clouds, and I had been reading constant reports of thunderstorm activity in the vicinity of Lassen. When I reached Red Bluff, I realized I had forgotten my mosquito repellent, so I stopped at a store and purchased the deadly chemical agent, and also bought a poncho, believing that even rain would be only a temporary deterrent to observing.
As I drove up the mountain, thunderheads began appearing, blotting out large parts of the sky. As I drove into the park, a few drops of rain hit my windshield. I remained optimistic, determined to observe under any conditions, and realizing that it was better to sit in the campground waiting for it to clear than sitting at home waiting for it to clear.
I arrived at the Summit Lake South campground to find TACos Jim Bartolini, Ken Head and Michelle Stone trying to fish her keys from the front seat of her locked van. They were successful as Michelle hooked them and fished them out with a contraption fashioned out of tent poles, tape and paperclips.
Apparently it had rained severely in the several days before I arrived -- there was abundant and prominent evidence of water flow on the ground in my campsite. The ground was reasonably dry, though.
The cloud cover waxed and waned as we ate our dinner. And the enthusiasm for observing waxed and waned amongst the group, in inverse proportion to the cloud cover. I was determined to observe even through holes in the clouds, and every time someone took a poll, I indicated I was going no matter what. Finally the time came to leave, and it was gradually getting less cloudy, so I headed out for the observing site, about 10 minutes away. Even at a dark site, we have to commute to our observing site, because the horizons at our campsite were lousy and there were trees blocking much of the sky.
It was cold and surprisingly damp at the 8200 elevation of the Bumpass Hell parking lot. Well, the dampness wasn't that surprising, because the thick nimbo-cumulus clouds had departed only minutes earlier. The sky was now mostly free of clouds, which seemed miraculous, considering what it looked like an hour ago.
Shortly after the sun set, dew began to be a problem. Tom Morris was next to me and he had a hygrometer which reported the humidity as 90%, so I took my usual anti-dew precautions -- leaving the lens cap of my finder on except when I was using it. This passive measure was successful for the entire relatively short session.
Waiting for it to get dark, I observed Mars. It did not show any surface detail during twilight, although it was obviously gibbous. The seeing was only fair. Venus was nowhere to be seen.
I had already decided not to pull an all-nighter the first night, because I knew I was tired from the drive, and because of my experience last month, in which I did pull one the first night, but was relatively unproductive during the extra time. It's better for me to do this when I am well rested, which is a good argument for staying in a motel rather than camping. But I digress.
I had recently acquired the 2-volume set of The Night Sky Observer's Guide, by Kepple and Sanner, and I wanted to try using it in the field. After looking over Mark Wagner's copy of the book last month, I knew this book would be a tremendous observer-oriented encylcopedic resource, comparable to, but different in emphasis from Burnham's Celestial Handbook.
Since I'm mainly interested in observing galaxies, and this is the middle of summer with the Milky Way, a generally galaxy-poor area, dominating the sky, and I am generally a little perverse, I decided to start the evening's festivities by hunting down galaxies in or near the Milky Way.
I opened the Spring and Summer volume to the chapter on Aquila the Eagle. I searched the reviewed objects until I found a galaxy (NGC 6814) on page 22. I also wanted to see whether I could find the object using only the charts in this book. The review was only for 12/14" scopes, so I figured that this object might be challenging for my 10". The finder chart was on page 15, starting in the tail of Aquila.
Each small finder chart includes one key star (Lambda Aquilae in this case), which can either be found on the main, full constellation chart, or on a smaller chart which shows the locations and scales of the smaller charts. Or, you can assume you know what star it is and begin starhopping immediately, which is what I did.
Of course, I didn't know which star it was, and I had great difficulty finding my quarry. Finally, I located the correct star on the main chart and I quickly used the small chart to star hop my way to the object via 20 Aquilae and 37 Aquilae. I noted NGC 6814 as "faint galaxy, diffuse, somewhat irregular, difficult".
And that was it for galaxies within the reach of my scope in Aquila! Man was I having fun!
Not wishing to leave Aquila, I decided to look at some open clusters using the only the charts in the NSOG. NGC 6795 was a very loose, big open cluster that blends into the Milky Way. NSOG notes that this is "listed as nonexistent in the Revised NGC", a source of amusement for me. I could see why someone might think of it as non-existent -- it was just barely discernable above the Milky Way visual noise.
6709 was another large, loose open cluster. 6773 was a medium-sized, sparse open cluster that was very hard to see in the Milky Way. This is catalogued as "nonexistent" in the NGC, and again I could see why. More amusement.
Although it was not particularly late, I began to tire, feeling the effects of the 4 hour drive. Also, dew was severe. I was worried about the effect of dew on the NSOG, and though the pages wrinkled a bit during the night, the next day, after drying out, they straightened right out, and the books did not seem any worse for wear.
About this time, Jay Freeman was observing Einstein's Cross with a white Celestron C-14 he calls "Harvey". Einstein's Cross is a gravitationally lensed quasar. It is very small and faint, and in high resolution images, you can see 4 images of the quasar forming a tiny box around the lensing galaxy. See http://www.seds.org/TAC/reports/98.12.19.3.html and http://www.seds.org/TAC/reports/99.08.11.html for his reports.
When I first looked in the eyepiece (at about 500x), I didn't see anything at all. I was a bit flabbergasted, because usually it is I who can see the faint thing nobody else sees in my scope.
I was amused when I heard Mark Wagner remark later, "There's nothing there!" when he first looked.
But as I waited, eventually an image gradually formed itself as my brain strained to integrate the few weak photons reaching my retinae.
I saw a single, featureless, shapeless and diffuse blob of faint light. It seemed slightly brighter at the center, but there were no stellar features. I must have looked for 10 or 15 minutes. Twice, I thought I saw two blobs vertically oriented, but I'm not sure and it was not a repeatable observation.
I returned to my scope and summoning my waning strength, finally departed Aquila for greener galaxy pastures. Galaxies are far and away my favorite objects to view in the night sky. The fact that they are also far more numerous than all other types of objects combined pleases me.
NGC 6928 and 6930 were a really nice little pair of faint galaxies just off the tail of happy little Delphinus, the cutest and smallest constellation in the sky. 6928 (mag 12.2) was the brighter, and was round and had a very stellar center. 6930 (mag 12.8) was a dimmer, diffuse oval. Being only about 4' apart, I was able to frame them both easily in my 10mm (142x) eyepiece.
I was starting to get very tired now, so I 'ruined' my dark adaption by looking at M33, the enormous Pinwheel Galaxy in the constellation Triangulum (The Triangle). I could see some mottling in the large diffuse circular image which presented itself in the eyepiece. I was surprised, but I usually don't look at big or bright objects when I am at a dark site -- I usually seek out faint stuff I cannot see from my backyard.
But large bright objects present new faces at dark sites, as I discovered with the Orion Nebula in January.
Finally, I decided to chase down some enormous galaxy groups in Pisces, but which I think of as being associated with Andromeda. I had heard about these groups from Gregg Blandin, a Blue Canyon regular who sold me the 10" scope I use now.
I pointed the scope to a likely looking place, based on galaxy densities in the Herald-Bobroff Astroatlas, and was immediately treated to a lovely spectacle of 5 galaxies in a straight line: NGC 384, 385, 383, 380 and 389. The brightest of these was mag 12.4, and the dimmest was 13.1, but none of them were particularly hard to see. They were all different, some having stellar centers, and others being diffuse ovals.
Since I could not possibly identify them using the H-B atlas, I sketched them and some surrounding stars. When I got home, I easily identified them from the sketch using SkyMap, a star charting and planetarium program.
Although this was obviously a promising area to hunt galaxies, I was completely exhausted, so I tore down and drove 10 minutes back to my camp and got ready to sleep.
If the first, somewhat abbreviated night could turn out so well after such threatening weather, I knew the next three nights would be just as great, and I eagerly thought about the views I was going to have as I quickly drifted to sleep.
| Date | August 11/12, 1999 9pm-1am (0400-0800 Aug 12 UTC) |
|---|---|
| Location | Bumpass Hell, Lassen, California, USA (40.457N, 121.5W) |
| Altitude | 8200 ft. |
| Instrument | Orion DSE 10" f/5.6 dob-newt |
| Oculars | 7.5, 10, 17, 26mm Sirius Plossls |
| Seeing | 6/10 Fair; a bit fuzzy |
| Transparency | 8/10 Very clear |