Event Date: July 1st
Time: 9:30 PM/2:11(.55), 5:00 AM (see NOTE*)
Brief
I have taken a long break from the Summer Triangle with all the recent planet talk. Now, as we begin the second half of the 2012 calendar and deep enough into the summer season, the Summer triangle gets alot of evening attention. All three stars rise before Sunset, with Vega rising the earliest about 4:30 PM (local). Deneb rises a little over an hour earlier with Altair doing so shortly before Sunset. With all three stars north of the celestial equator and our Sun below the horizon for only about 10 hours, we see these stars still well above the horizon just before morning twilight washes them out at about 5:30 the next morning.
*NOTE: The three images that I will show below are *out of order time-wise, yet still in sequence: early evening when the Triangle is visible on the rise, late night hours when it transits, and the aforementioned 5:30 AM time for when we still see the stars fading in the west.
Time: 9:30 PM/2:11(.55), 5:00 AM (see NOTE*)
Brief
I have taken a long break from the Summer Triangle with all the recent planet talk. Now, as we begin the second half of the 2012 calendar and deep enough into the summer season, the Summer triangle gets alot of evening attention. All three stars rise before Sunset, with Vega rising the earliest about 4:30 PM (local). Deneb rises a little over an hour earlier with Altair doing so shortly before Sunset. With all three stars north of the celestial equator and our Sun below the horizon for only about 10 hours, we see these stars still well above the horizon just before morning twilight washes them out at about 5:30 the next morning.
*NOTE: The three images that I will show below are *out of order time-wise, yet still in sequence: early evening when the Triangle is visible on the rise, late night hours when it transits, and the aforementioned 5:30 AM time for when we still see the stars fading in the west.
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As I have shown repeatedly for morning journals of the Triangle, Vega and Deneb transit very high, with Vega (nearly) at zenith when it does, seen from mid-northern latitudes. Deneb is a little further from zenith at transit for our latitude here at almost 38º N, yet hardly noticeably given its excellent declination. Altair arcs high in the south, being 30º south of Vega and about 38º south of Deneb. Therefore, as image 3 shows, Altair is lowest to the horizon and first to set after the Sun comes up. This will be more noticable in August and September, when I show the Triangle lower towards the west and northwest horizon.
Look as a reminder, how the celestial grid reminds us of the declination differences, particularly of Altair.
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