02/13/2018 – Ephemeris – Looking out the thin side of the Milky Way’s disk
Ephemeris for Fat Tuesday, February 13th. The Sun will rise at 7:46. It’ll be up for 10 hours and 22 minutes, setting at 6:08. The Moon, 2 days before new, will rise at 7:07 tomorrow morning.
With Orion and the winter stars grabbing our attention in the south, let’s look to the northeast to southeast where the stars are not as many, and with the exception of the Big Dipper and some other stars, not as bright. The inner stars of the Big Dipper are part of a sparse star cluster only about 80 light years away. The reason for the sparseness is that here we are looking out the thin side of the Milky Way’s disk. It will be our spring sky. To the west is the autumn evening skies. The thick part of the disk runs from the south-southeastern horizon, to just west of the zenith to the northwestern horizon. The reason the Milky Way isn’t as bright as the summer sections, is that we are looking away from the center to the outer spiral arms. We are in a small arm with the Great Orion Nebula.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
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