Saturday, September 12, 2015

AM Saturday, September 12, 2015 - Notes


  During the short work week between the mornings of Tuesday, September 8th - Friday, September 11th the sky conditions didn't cooperate too well with my observing plans. This unusual stretch of hot and humid weather we'd been experiencing all month was changing as two slow-moving cold fronts passed through our area. I'd get some clear skies on some mornings, and get glimpses of the rising Winter Constellations. But there were usually scattered thin clouds around and light fog in the air, and the patio was usually damp from light showers that had fallen during the previous evening. I didn't think it was worthwhile to get the telescope out and try to observe under these circumstances.

  The second cold front of the week moved through during the day on Friday the 11th, and it was a cool, misty, sometimes rainy day with low, gloomy clouds everywhere. By the time I was driving home around 2:00 AM on Saturday the 12th, however, the rain had been over for hours and the sky was clearing out. A steady breeze had dried out the pavement a little and also kept a lot of low fog from forming. I thought that maybe my chance to observe variable stars was finally here. But every time I checked outside the back door between 3:00 AM and 5:00 AM, I was discouraged. Low clouds continued to march across the sky in waves (altocumulus and raggedy-looking cumulus) and the pavement of the patio was still damp. (This is always a concern since I plug the mount into the outdoor socket and the cord lies on the concrete.) Though it was mostly clear, I still didn't think it the ground and sky conditions merited taking the 10" scope outside.

  I stayed up very late, and went outside around 6:10 AM. At this time the sky had cleared dramatically! I believe the limiting naked eye magnitude was at least 5.0 since I could see a lot of the fainter stars in Orion, Taurus, and Gemini that I normally can't see in this light-polluted area. The sky to the East and Southeast was very dramatic. Though I've seen Orion several times in the morning sky over the last month, this morning it was high in the sky and dramatic, with Rigel and Betelgeuse blazing away. I could even make out the Orion Nebula (though, of course, it looked star-like without optical aid). I also had my first looks of the season of Procyon and Sirius sparkling away. At this time there was just a hint of the first light of dawn in the east. The temperature in the low 50's°F and it felt very chilly in comparison to the past several mornings. The sounds of singing insects were very subdued.

  However, the really showy object was Venus! This was my first look at it as a morning object; I'd last seen it low after sunset in July. It was so much brighter than any of the stars that it just looked unreal, like it was on fire! It was just peeking over the edge of the roof of our house from the edge of the patio.

  I drew a very rough sketch of how it looked below, though this drawing really doesn't do justice to how pretty it really looked:



  If I'd stayed up slightly later and had a better look at the eastern sky, and especially if I'd had binoculars handy, I probably could have also spotted Mars just 10 degrees or so to the lower left of Venus. And by 6:30 AM (though the sky would have been getting very bright at the time before sunrise) Jupiter also might have been glimpsed, just rising over the horizon, below and to the left of the star Regulus in Leo. This would have been a challenge, though, and almost certainly would have required binoculars. The Moon rose this morning just half an hour before the Sun, and it probably wouldn't have been visible in that very bright, very low eastern sky even with binoculars.

  New Moon occurs at 2:41 AM EDT Sunday September 13 (6:41 UT September 13). There is also a Partial Solar Eclipse at that time, but, of course, nothing of it will be visible from Indiana or anywhere near North America. It will be seen from South Africa and part of Antarctica.

  Venus will continue to blaze away in predawn skies from now through the whole winter, and even through May of 2016 (though it will be getting very tough to see by early Spring). In late October it will have a showy conjunction in Southeastern Leo with Jupiter and Mars. I'll keep watching the show when I can and try to add more sketches as time goes by.

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