Event Date: November 10th
Time: 7:36(.36) PM/11:22(01) PM
Brief
Yesterday, I mentioned that the Andromeda constellation and galaxy were both far enough north in declination that as seen from our latitude. As a result, we see it at two points in the sky of which it reaches maximum azimuth, as well as altitude. To learn more about this, let's look at those here. As I include the celestial grid, the first image being the early evening when it is rising in the east; the second image the galaxy during the late evening hours when it is high in the west. Since both the center of the constellation and the galaxy are just a fraction of a declination of a degree different, using the galaxy alone works fine.
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click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.
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Detailed
The images show the maximum azimuth separation from north, before the galaxy reverses azimuth direction, back to north. The altitude is 68º 3'. When we notice Andromeda in this manner, it reminds us that if we are more north by about 12º, that the galaxy would be circumpolar. Those who see it at/near the western U.S./Canadian border, can catch it all night long above the horizon. Those even further don't see it transit as high, yet can see it higher above the horizon more hours of the night. Then again, the further south a viewer is, the less hours the galaxy is above the horizon. Just as we see some deep-sky object such as the Lagoon Nebula and Butterfly Cluster arc for only so many hours above the southern horizon, those in low-mid southern latitudes may see it similarly as we do for the Andromeda galaxy, for more than 18 hours per [sidereal] day.
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