Iceland is located over the Atlantic Ocean, more than 60 degrees north latitude. In winter in the northern hemisphere in January, the direct point of the sun is in the southern hemisphere. The direct point of the sun goes back and forth between 23 degrees and 26 minutes north and south latitude every year, which means that the direct point moves 46 minutes and 52 seconds every year. On the solstice of winter (65438+February 23rd), the sun shines directly on the Tropic of Capricorn. At this time, the extreme night phenomenon occurred in the north of 66 degrees 34 minutes north latitude (Arctic Circle). In June+10, 5438, the direct point of the sun moved northward to about 20 degrees, that is, the area north of 70 degrees north latitude in the northern hemisphere was still extremely night. Iceland was just over 60 degrees north latitude. At this time, Iceland can save time to cover the sky.