David B. Williams

We enjoyed an excellent spring meeting in Rockford. I'll admit that I wasn't a strong supporter of this invitation in past years - it's always best when meeting sites have some "sizzle" to increase attendance. But in fact we had a good turnout, saw some AAVSO'ers who don't usually come east for the fall meetings, and the program was varied and interesting. I was surprised by how many members were interested in learning how to write a scientific paper. We even got to meet a Tyrannosaurus Rex!

As usual, I returned home with fresh enthusiasm for variable star observing. And just as usual, the weather failed to cooperate. So when last Saturday looked good, I was determined to make the most of it with an all-night session at a club observatory site, one of three remote sites I can use when darker skies and unobstructed horizons are worth an hour's drive.

I had strained my lower back earlier in the week so I left the heavy equipment at home. I took my trusty collection of binoculars (6x30, 10x50, and mounted 20x60s) and a 5-inch f/5 refractor. Having checked various predictions and ephemerides, I knew there would be plenty to do with this minimal equipment. Lesson 1: plan your observing so that you get the most return for your time and effort.

I intended to catch up on many regular AAVSO stars and time the minima of three eclipsing binaries: Z Her, UX Her, and W UMi. Z Her has an inconvenient period (3.99 days) and I don't think I have caught a minimum since the 1960s, so I didn't want to miss this one.

As usual in Indiana in July, it was a very dewy night. A couple of other club members set up at sunset, looked at Jupiter and the Ring and M13, then gave up and departed before midnight. They couldn't fend off the dew. But I had the 5-inch and the 20x60s wrapped with plumber's heat tape, providing lots of warmth to keep the optics above the dew point. Lesson 2: come equipped and prepared for the prevailing conditions.

The first couple of hours were busy. I had to find each EB field, check the comparison sequence, and begin making estimates at 15-20 minute intervals. In between, I caught up on many variables I hadn't been able to observe for several weeks. Good old W Cyg was about as faint as I have every seen it. R Sct was down in a primary minimum. R CrB and RY Sgr were both at maximum, no excitement there. But the two symbiotic variables AG Dra and Z And were brighter than I had ever seen them. Lesson 3: expect the unexpected (then look twice to make sure).

I was momentarily confused when I looked for R Cas, which was invisible in binoculars the last time I looked. Now it had popped up to sixth magnitude. And I had estimated chi Cyg at 6.1 just ten days ago, and now it was 4.4. I lowered the binoculars and looked up at Cygnus - yes, chi was a naked-eye star, plain to see.

Several times per hour, I was estimating UX Her with the 5-inch and Z Her and W UMi with the 20x60s. UX Her reached minimum first, and as it began to rise, it seemed that it was brightening faster than it had dimmed. I thought my observations were going to produce a useless, asymmetrical light curve, but I doggedly kept going, making the best estimates I could. When I plotted the data the next day, the minimum turned out to look pretty good after all! Lesson 4: estimate what you see, not what you think you should be seeing.

Around 3 a.m. even my industrial strength dew-zapping technology began to huff and wheeze. Ground mist rose from the surrounding fields of prairie grass, and I had to give the eyepieces an occasional blast from a hair dryer to keep them from fogging up, but the toasty-warm objectives on the 5-inch and the 20x60s stayed dry all night.

Just before dawn, with Venus low and bright in the east, I managed to observe Mira, the first variable star to be recognized, down in the southeastern sky, wedged between the glow of a bright gibbous moon and the horizon haze. It was a perfect end to a good night, during which I collected 43 estimates of AAVSO stars and 49 estimates for the three eclipsing binaries.

For more than 90 years, countless AAVSO'ers have experienced similar nights. There's a special satisfaction in packing up your equipment in the dawn's early light, knowing that you have collected some useful data that will be archived and made available to the research community. The weather forecasters say next weekend should be clear too. I think I'll do it all over again.

From the Director

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