Lately as I ride across the pedestrian bridge at sunrise, I have noticed the sun has been rising in the north. Having been informed that the always rises in the east, I found this perplexing. The trouble turns out to be the accumulation of two interesting factors.
1) The pedestrian bridge does not head due north, it is rotated 15 degrees towards the east. Picture:
So believing the bridge to be north-south was problem one.
2) The sun does not rise in the east. Tomorrow (9/4/2009) it rises exactly 9 degrees north of east. But back in July when I was first having the problem, it was rising 28 degrees north of east. As late as August 4, it was 21.4 degrees north of east. Moreover just before sunup, the sun is another couple of degrees north of east, when its light is beginning to fan out across the sky.
3) Accounting for the early light makes 30 degrees north + 15 degrees of bridge rotation, so the sun APPEARS to be rising at 45 degrees north of due east and that surely looked wrong. I noted this out fearing some sort of cosmological malfunction of my brain or dire state of misinformedness.
4) The sun does not rise in the east, it rises in the north east, in the summer and the south east in the winter. This is paradoxical since the winter sun rides lower in the southern sky as the northern hemisphere tilts further away from it. It rises in the east only one day of the year. This year that will be September 23 at 7 am CDT, a day after the equinox. After this the sun heads south of east for its rising reaching a of maximum southness of east of 28.6 degrees around the solstice, December 21.
5) Riding on the bridge, the sun will appear to rise in the east on Halloween morning at 7:15 am in a suitable tribute to my distress. The next day we reset our clocks introducing a new kind of biological confusion.
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