Event Date: December 27th
Time: 4:00 AM
Brief
Yesterday, I showed the winter circle (or "G") of stars during the late evening hour of 9 PM...late for some people anyway! This evening, as mentioned at the end of that entry, I will show them here while all are still seen above the horizon at mid-northern latitudes. For this one, the clock is forwarded 7 hours ahead of yesterday's entry, with the stars displayed. Notice how Capella, which rose as "early" as 1:22 PM the previous day, is still over 5 1/2 hours from setting. Just by looking at the image, that may not be easy to calculate even using the gridlines, yet I obtained these times using the info from my software for this latitude, naturally!
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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
Using the celestial guidelines once again, as I did yesterday, southern stars such as Rigel and Sirius are early to set in comparison to those far north such as Pollux and Castor. Even though Sirius is the last to rise, it sets after only about 10 1/2 hours, while starts such as Capella, Castor and Pollux spend extra hours above the horizon. The gridlines become smaller and smaller circles as we see them closer to the north celestial pole and therefore, stars close to the pole never set at all, seen from this latitude of about 38º.
Keep watching the large group of bright stars each evening, as they rise about 4 minutes earlier each evening. By spring, some are setting before the Sun does, depending which week you are viewing the western sky.
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