Event Date: May 30th
Time: 3:00 AM
Brief
The Spring Arc is seen high in the sky during the late evening hours at this time of year, as seen from mid-northern latitudes. The handle stars of the Big Dipper are very high in the north. Arcturus on the other side of zenith is seen high in the south at a similar altitude. Spica on the other side of the celestial equator, ends up setting first, the same way--and reason--that it rose last. Here is a reminder of where the stars can be seen during early morning hours now before dawn, and before Spica sets. Unlabeled Saturn is seen near Spica, less than 5º away.
Time: 3:00 AM
Brief
The Spring Arc is seen high in the sky during the late evening hours at this time of year, as seen from mid-northern latitudes. The handle stars of the Big Dipper are very high in the north. Arcturus on the other side of zenith is seen high in the south at a similar altitude. Spica on the other side of the celestial equator, ends up setting first, the same way--and reason--that it rose last. Here is a reminder of where the stars can be seen during early morning hours now before dawn, and before Spica sets. Unlabeled Saturn is seen near Spica, less than 5º away.
Detailed
The celestial grid is included above to further show the declinations of each star. Spica is positioned at a good altitude early in the evening, seen from most places on Earth. The exception is that of far-north latitudes where there isn't enough nighttime to see it long anyway; it just arcs over the horizon at latitudes just south of the arctic circle, and doesn't clear the horizon at all at latitudes close to the north pole. The opposite holds true with Arcturus, which is a little more north than Spica is south. As for the Dipper, the stars are circumpolar from many latitudes north, and they do not clear the horizon as seen from most southern latitudes. For the second image, I will take us to the same latitude south as we are north: Box Hill, Australia, which I have used before, at 37º 49' S. The time zone difference is 18 hours, being mid-evening there, for the placement of the stars.
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| click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp |
Notice that with the exception of Alkaid, the rest of the Dipper stars are below the horizon, and none of them transit above the horizon this far south. As for Arcturus, it is seen for only 10 hours above the horizon as seen from this latitude. Spica is seen for 13 hours, 14 minutes-- a big contrast compared to the time durations from our latitude, where Spica is up for only about 11 hours, and Arcturus up for about 14.
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