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cyswxman
2006-Jul-29, 04:22 PM
Simple question: What time is the first sunset of the season for Barrow, AK?
Being north of the Arctic Circle, the sun has been above the horizon continuously for some time now. I call up a table from the U.S. Naval observatory, and other sites, and they show first a SUNRISE time on Aug 2nd.
But you cannot have a sunrise if it did not set earlier!

cyswxman
2006-Jul-29, 04:47 PM
I think I figured it out. The first sunset of the season in Barrow is Aug 2nd at 1:05 AM Ak ST.
It's confusing in that the table prints a sunrise time after a sunset time on the same day.

grant hutchison
2006-Jul-29, 05:10 PM
That looks like it. There are two sunsets listed for 6 August, one just after midnight and then another just before.
Evidently the sun sets and then rises again just after midnight for a few days in August because of Barrow's location within the Alaska time zone: for those few days, "night" doesn't span midnight by the clock. Then, as the night lengthens, sunset gets earlier and earlier, until it pops back through midnight into the previous day, where it "should" be.
Interesting. :)

There's also no sunset listed during May 6th, despite the fact that sunrises and sunsets go on for several more days. It's the same effect happening in reverse: the sun that rises on May 6th sets in the early minutes of the following day.

Grant Hutchison