Howling at the Moon

Contrary to conventional wisdom, I observe variable stars during full moon. No, it's not my favorite time of the lunar cycle to observe due to the sky brightness, but I think you should take advantage of a clear night regardless the phase of the moon. Once in a great while a syzygy occurs and even full moon isn't such a bad time.

A syzygy is the alignment of three or more celestial bodies in the same gravitational system along a straight line. The word is usually used in context with the Sun, Earth, and the Moon or a planet. Solar and lunar eclipses occur at times of syzygy.

February 20th was the last total lunar eclipse for North America until 2010, and it happened to be the first clear night here in 2008 that wasn't -50C, so I headed out to the observatory as twilight ended. The moon was already well above the horizon in the east, parked slightly NW of Saturn in Leo. Between the snow-covered ground and the full moon it was impossible to tell twilight had ended. It was bright enough outside to read by. The snow underfoot crunched sharply as I walked out to the dome, a sign it was already pretty cold outside, but the forecast low was for -20C, seasonably cold for a Michigan night in February, and bearable as long as there is no wind to speak of.

Orion was just about due south, and neither the telescope nor I wanted to move very far from our parked position, so I began observing in and around Orion first. The seeing was pretty steady and there was no haze or cirrus. On a good night like this I can easily see stars down to about 14.5 from the celestial equator to about -20 declination with the 12 inch. Full moon's added charms had reduced that to around 13.8. I checked off three stars in Eridanus and then moved on. Fortunately, the southernmost stars in Canis Major on my list were both fairly bright, 10th magnitude, so making the estimates there was easy. The Moon was rising higher and the eclipse hadn't started yet, so the sky was getting brighter as I moved into Orion.

It was getting colder, so I quickly finished my program stars in Orion and went inside to have some coffee, warm up and wait for totality.

About twenty minutes before the last bit of bright white Moon disappeared I stepped back outside and looked at the moon with binoculars again. The back yard was noticeably darker and most naked eye stars visible on a moonless clear night were pretty easy to make out. I headed to the observatory hoping to get dark-adapted by the time totality began, so I could take advantage of this 'bonus' dark time in February.

I pointed the telescope up towards Auriga. It looked like the darkest part of the sky, was riding nice and high, and Auriga is chock full of interesting Miras. At this point the dogs in the area all seemed to notice the moon was disappearing and began barking. One would start barking here, another one would answer him off in the distance, and the racket grew louder and louder as all the dogs within earshot started sharing eclipse notes. As the moon turned completely dark
orange-red the coyotes began howling. This got all the dogs going again. As if that weren't enough to scare away whatever sky dragon was eating the moon, the donkey on the horse farm north of me started braying as loudly as I've ever heard him. I found it somewhat comforting to know I wasn't the only jackass outside freezing my butt off as the Moon slipped into the Earth's shadow.

The canine cacophony eventually subsided and I enjoyed the hour of totality observing Miras in Auriga. About the time the moon started to escape the grip of eclipse, both the telescope and I were pretty well frozen. My fingers were starting to hurt and the corrector plate was frosted on the inside about an inch all the way around the central obstruction. The dew heater can't keep up with pointing straight up on a -20C night for long. I packed it in, closed up the dome, took a last quick tour of the moon in binoculars and headed for the warmth of the house.

In the morning I noticed the blue jays at the bird feeders seemed a little grumpier than usual. They probably didn't sleep very well with all the racket from the dogs and the donkey the night before. Me, I slept like a frozen rock.

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