Monday, July 24, 2006

Twice a year

The sun's setting pretty much straight in the west here in Portland. Time for that midsummer night's dream...

CORRECTION, 6:37 p.m.: Looks like old Sol's going to hit the horizon still a bit north of due west. But it's getting close. No harm in starting that dream a little early. We still come this way only twice a year.

Posted by Jack Bogdanski at July 24, 2006 06:20 PM | TrackBack (0)


Comments

That's presuming, of course, that anyone can actually fall asleep and *stay* asleep given the temperature...

Posted by: Betsy at July 24, 2006 07:08 PM

I'm a liitle confused. Is that magnetic west? I'm not sure I understand the geometry of it setting north of true west, seeing as how we're not at the tropic line...

Posted by: Don Smith at July 24, 2006 10:26 PM

Jack, you are about two months off-Sept. 21st is usually the date, happens every year about the same time. Has nothing to do with magnetic bearing. Signed: Solar Architect

Posted by: Jerry at July 25, 2006 09:05 AM

Now i'm really confused. How is the Equinox the date the sun sets in the west?

Posted by: Don Smith at July 25, 2006 10:27 PM

Never mind. With much expermentation with a grapefruit, a flashlight and some toothpicks, I think I've got it.

Posted by: Don Smith at July 25, 2006 10:34 PM

Mr. Ward is correct. We get the Manhattan Stonehenge effect (see Jack's entry for July 12) on most of the gridded streets on or within one day of the vernal and autumnal equinoxes, because most of Portland's street grid is oriented north-south and east-west. The grid in the central city (the SW part of downtown) is rotated about 21 degrees clockwise from true north, and as a result downtown Portland's "Stonehenge sunsets" arrive (I think) in late May and early August.

Posted by: Isaac Laquedem at July 26, 2006 01:02 AM



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