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The keeping of the Sabbath in space and the polar regions of the Earth like Alaska presents unique issues for Sabbath keepers. In the north of the Arctic Circle and south of the Antarctic Circle, a single period of daylight can last for a month or more during the summer, and the night lasts for a similar length of time in the winter.
The Bible says, “It shall be unto you a sabbath of rest… from even unto even, shall ye celebrate your sabbath” (Leviticus 23:32). This means that the Sabbath should be kept from Friday sunset to Saturday sunset.
Therefore, in the further regions of the earth and in countries where the sun doesn’t go down like the Polar zone, the timing of the Sabbath should be adjusted to the International Date Line (i.e., permitting local rest-day adjustment, Esther 9:16–19) and believers may determine the Sabbath by the longitude that are further south or further north depending on which Polar zone they are in. And for those who live in Alaska, they can follow the time zone of Portland, Oregon. This way, Sabbath keepers in those areas, can rely on the consistent cycle of day and night in 24-hour periods that are commonplace in most of the world.
God understand the limitations of those that live in the extreme regions of the earth. And He will take their best efforts to keep His Sabbath holy as adequate and acceptable when covered by the blood of His Son.
In His service,