The 85th parallel north is a circle of latitude that is 85 degrees north of the Earth's equatorial plane, in the Arctic. This parallel lies entirely within the Arctic Ocean.
At this latitude the entire sun is visible for 24 hours, 0 minutes during the summer solstice and during the winter solstice, the latitude is under total nighttime during the entire day. This is the first parallel by degree to do so. The Arctic Circle is the latitude where the center of the sun is visible at midnight during the summer solstice, as opposed to the entire disk.
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