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The Sky This Week, 2017 August 22 - 30

Post-eclipse impressions.
IMG3248asmall.jpg
Total Solar Eclipse of 21 August, 2017, 15:32 UT,
imaged from Smith's Ferry, Idaho by Geoff Chester
with an 80mm f/6 Antares Sentinel refractor and a
Canon EOS Rebel T2i DSLR, 1/250 sec @ ISO 200

The Moon moves into the evening sky this week after her coast-to-coast rendezvous with the Sun. First Quarter occurs on the 29th at 4:13 am Eastern Daylight Time. Look for the Moon on the evening of the 25th, low in the western sky as evening twilight falls. She forms an attractive triangle with Jupiter and the bright star Spica, setting up a great photo opportunity after sunset. By the end of the week she hangs out near Saturn, passing the ringed planet on the evenings of the 29th and 30th.

I’ve just returned from viewing what can now be called the "Great American Eclipse", having successfully observed it from the small hamlet of Smith’s Ferry, Idaho on the banks of the Payette River. I’m quite sure that this eclipse was probably seen by more people than any previous one in history. Most of the people who flocked to the 70-mile wide path of totality were rewarded to see the experience of a lifetime, with relatively few "clouded out". My view from Idaho was spectacular. This was my fifth total solar eclipse, and it was hands-down the most spectacular! The altitude of my observing site, about 4500 feet, led to extremely clear and transparent sky. The smoke from forest fires in Oregon passed well south of us, and as totality began the delicate wisps out the outer solar corona shone with a most sublime pearly glow. Several red prominences adorned the Sun’s limb, and the planets Mars and Venus broke into view. For the brief moments of totality the sky was suffused in an eerie deep twilight glow as most of the light from the Sun came from its chromosphere and inner corona. Most of the 30 or so people at our observing site had never seen a total solar eclipse before, and their reactions reflected the magnitude of the spectacle. Shouts of joy and awe wafted over our group, along with the distant sounds of the 100 or so people camped across the river. Our 2 minutes and 12 seconds of darkness went by all too quickly, leaving everyone yearning for more. It is no wonder that people who have seen one eclipse catch the bug to see another one. Fortunately, we won’t have to wait too long for our next American eclipse. On April 8, 2014 a four-minute eclipse will sweep northwest across Texas, Arkansas, Missouri, Illinois, Indiana, Ohio, Lakes Erie and Ontario, northern New York, Vermont, New Hampshire, and Maine.

It’s time to bid a fond farewell to Jupiter for this apparition. The giant planet is still visible during evening twilight, but he now sets shortly after twilight ends. He does go out with a nice photo opportunity, though, joining the waxing crescent Moon and the bright star Spica on the evening of the 25th.

Saturn crosses the meridian at sunset and becomes visible shortly thereafter. The ringed planet spends the next couple of hours wheeling into the southwestern sky. You have this time to enjoy viewing him in the telescope. Almost any instrument will show his rings, and I had great fun showing him off to some of our fellow eclipse watchers in Idaho. Despite the telescope’s modest size, just 3.1 inches of aperture, the view of Saturn was almost as thrilling as seeing the eclipse itself! Saturn reaches the second stationary point of this year’s apparition on the 25th. He will gradually start moving eastward against the stars over the next few weeks. Look for the Moon near the planet during the evening hours of the 29th and 30th.

Venus passes out of the constellation of Gemini and enters the faint group of stars that make up Cancer, the Crab. By the end of the week she is closing in on the scattered star cluster known as The Beehive. This cluster is just visible to the naked eye on clear winter nights under dark skies, but you should be able to spot it in binoculars as Venus closes in.

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