The periods of incomplete darkness following sunset and preceding sunrise. Twilight is designated as civil, nautical, or astronomical, as the darker limit occurs when the center of the sun is 6 degrees, 12 degrees, or 18 degrees, respectively, below the celestial horizon.

I don't know which one is used to determine "sunset".  Ellen and James White at first believed 6pm to 6pm was OK to determine Sabbath hours, but Ellen was later shown by an angel that it should be from "even to even".

In the SOP it is written regarding the question of what Eskimos should do, and it says basically that God never intended for humans to live there, and those who do live there can do something sensible to keep the Sabbath.

My question is: What do you do about flying around the date-line?  One time i left Japan right at sunset on Friday evening, and landed Friday morning in LA.  Did i break the Sabbath?  And what about those who start out on Friday morning and land at sundown on Saturday - do they miss one Sabbath?  Again, i think we need to be sensible in all this.  Personally, i try to avoid all that by flying the other days of the week

Thank you for your comments.

I found this interesting article:

http://www.eternalcog.org/ecgarticles/sunsetordark.html

It quotes lots of Bible verses explaining that Sabbath begins at sunset not twilight.

I agree. My aim is to be ready an hour before sunset today. I am contemplating waiting an hour after sunset tomorrow before launching into the activities of a new week.

During our holiday we spent a Sabbath in high mountains. We could not see the sun set over the horizon, rather we watched the sunlight retreat up a peak as the shadow advanced. when did Sabbath begin in that location?

The times of rise and set phenomena cannot be precisely computed, because, in practice, the actual times depend on unpredictable atmospheric conditions that affect the amount of refraction at the horizon. Thus, even under ideal conditions (e.g., a clear s ky at sea) the times computed for rise or set may be in error by a minute or more. Local topography (e.g., mountains on the horizon) and the height of the observer can affect the times of rise or set even more. It is not practical to attempt to include such effects in routine rise/set computations.

The accuracy of rise and set computations decreases at high latitudes. There, small variations in atmospheric refraction can change the time of rise or set by many minutes, since the Sun intersects the horizon at a very shallow angle. For the same reason, at high latitudes, the effects of observer height and local topography are magnified and can substantially change the times of the phenomena actually observed, or even whether the phenomena are observed to occur at all.

http://www.adventist.org/sun/help/

Options:
1/ Follow visual observation only.
2/ Follow clock only.
3/ Follow a combination of clock and observation.

From your answer, it seems you are advising option two. If so, then this would be relevant to your statements regarding Sabbath observance in the artic circle.

Exodus 31:12-18 shows that the death penalty was administered to Israelites who broke the Sabbath. They didn't have electronic watches nor computerized sunset tables. They had the sun to go by.

http://www.biblestudy.org/bibleref/holy-days/when-does-the-sabbath-begin.html

This is a very interesting article explaining Sabbath observance in unusual situations e.g. dateline, polar regions and elevation.

I started this post because I had been at high altitude with no possibility of observing the setting sun. My husband and I watched the beautiful scene of the reflected sunlight advancing up a mountain peak. From my reading, I have concluded that sunset occurred when there was no light reflecting from the peak i.e. it was in shadow.

This is based on the understanding that there is a distinct dividing line between day and night called sunset. In a normal situation, the sun is setting when there are shadows and the sun can be observed disappearing over the horizon. Sunset is when there is still light but the sun is not visible. Night is when it is dark after this period of fading light.

Ellen White:
Before the setting of the sun, let the members of the  family assemble to read God's Word, to sing and pray. There is need of reform here, for many have been remiss. We need to confess to God and to one another. We should begin anew to make special arrangements that every member of the family may be prepared to honor the day which God has blessed and sanctified. {CG 529.1}

God be with you as you set a proper example

http://www.timeanddate.com/worldclock/sunrise.html

 

use this to plug in any where on the globe sunset times

That's so cool!

I use Time and Date all the time for my sunset times, but had never actually seen that page that shows all the civil, nautical, twilight etc. times in such a nice, graphical way :)

BTW, newbie, could you please select all your comment, then go to "Font Size", and choose "12pt"?  Your writing is so small, and my eyes are getting so old.....

so I changed the font and it looked the same to me...

here is 14...maybe that is better...

I was late starting the opening Sabbath worship because I left my keys behind.

 

Unfortunately it seems something usually comes up. However, if I hadn't aimed for the correct time, then we would have started even later. I heard later that other groups started an hour or more late. I was pleased that we started almost on time.

Over all the retreat was a wonderful blessing. Thank you for asking.