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The Sky This Week, 2010 August 24 - 31

The Joy of Vacation Stargazing
MoonVen_100814_01small.jpg jupc8_100814_0605_01small.jpg

Spica, the Moon, Mars, Venus, & Saturn
Imaged over Hay Harbor, Fishers Island, NY,
2010 August 13, 20:45 EDT
Canon PowerShot S2IS, 10 sec. @f/5, ISO 100

Jupiter, with Io & Europa
Imaged from Fishers Island, NY
on 2010 August 14, 06:05 UT

The Moon begins the week in her bright full phase, then wanes in the late night and early morning sky. Full Moon occurs on the 24th at 1:05 pm Eastern Daylight Time. August’s Full Moon is popularly called the Green Corn Moon, Grain Moon, or Sturgeon Moon. Luna spends most of the week drifting through the faint stars of the rising autumnal constellations. Her only encounter with a bright object occurs on the night of the 26th – 27th, when she rises with the bright glimmer of Jupiter and accompanies the giant planet through the morning hours. By the end of the week she begins to encounter the westernmost of winter’s bright stars as she closes in on Aldebaran and the Pleiades star cluster.

By the end of the week the light of the Moon is forestalled until around midnight. You’ve also probably noticed by now that the time of sunset is rapidly becoming earlier each night, so you will have several hours of darkness to enjoy the culmination of the summer constellations. Having just returned from a couple of weeks at a location with little light pollution and virtually no smog I can attest to the sublime beauty of the summer Milky Way and the bright stars that lie sprinkled through it. From the familiar "W" outline of Cassiopeia in the northeast, past the bright blue stars of the Summer Triangle overhead, down to the ruddy glow of Antares in the southwest, the galaxy holds a trove of wonders for skywatchers with and without optical aid. Some of my favorite moments from vacation were spent in a beach chair in the back yard of our house, picking out some of the more obscure asterisms and constellation patterns that inhabit this stretch of the sky. Occasional glances through my binoculars or 3.1-inch rich-field telescope kept me up until the wee hours, thoroughly entranced by the sights I’ve seen in many previous years from this spot. Clear skies on a dark island never get old! Summer stargazing is still at its best, and if you’ve got late summer vacation plans it is well worth it to stay up late a few nights while you’re away!

Over the past couple of weeks I hope you’ve had a chance to watch the interesting planetary dance in the southwestern sky during evening twilight. Bright Venus flirted with dimmer Saturn and Mars, and all were joined by a crescent Moon on the 13th. Saturn has been left behind by Venus and Mars as they continue to glide eastward against the stars. This week the two planets close in on the star Spica, which Venus will pass by the end of the week. On the evening of the 30th the planet will be just one degree south of the star. Mars will pass the star next week.

Bright Jupiter rises at around 9:00 pm EDT as the week begins. He gets a visit from the waning gibbous Moon on the evening of the 26th, and by the beginning of September he comes up at 8:30 pm. I had my first good look at Old Jove on vacation, and I can now verify that his telescopic appearance is very different that it was last year. His usually prominent South Equatorial Belt is now completely gone. This actually helps to bring out the view of the famous Great Red Spot, which over the past several years has almost blended in with the darker belt. It now stands out on its own and should be an easy sight in smaller telescopes. Jupiter will reach opposition in a few more weeks, so it promises to be an entertaining apparition this fall!

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