Sunday, October 7, 2012

Polaris, and Big Dipper stars labeled

Event Date: October 13th
Time: 6:30 AM


Brief

   This morning's entry is a reminder of where the Big Dipper is during morning twilight, seen getting higher in the north.  As we see it earlier in the morning, it is standing on the tip of its handle, which as a reminder, marks the long tail of the Bear.  For a reminder of why the tail of the bears are long, including that of Ursa Minor (Little Dipper handle), refer back to this myth:
Here is the Big Dipper in the northeast, already well placed.
click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   As each morning passes, we see the Dipper slightly higher in the sky, although not too noticeable, considering that it is close to the north axis in comparison to stars closer to the equator.  As a reminder, most of the stars of the Dipper are circumpolar as seen from our latitude, with Alkaid as the only exception; one would have to be a few degrees further north to see it high enough to never set.
   Also, at this time this morning, the popular pointer stars of Dubhe and Merak are at almost exactly the same altitude, within a quarter of a degree of each other.  The way I show them above at exactly the northeast azimuth, it allows a straight line to be drawn through them towards Polaris...almost anyway!  Remember that nothing is every perfect, yet close enough for us to determine which star is Polaris.  When looking towards that part of the sky, Polaris outshines all other stars within a binocular field.

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