Polar Zmanim On The Antarctic Cruise

[MeirS]

The difference between Shkia Haniris and Shkia Amitis is much greater in polar regions. The zmanim varied by as much as 30 minutes IIRC.

Good point. Obviously t's by degrees and would change by location. My research was done for 11213.

For our purposes, the consensus from nearly everyone is that Shabbos starts at Shkia and ends at Alos on Sunday. However, what if you only have Shkia Haniris and not Shkia Amitis? For our dates this could have happened between the latitudes of 65.17 and 66.
Do you start Shabbos at Shkia Haniris? When do you switch to a Polar Model of zmanim such as the Ben Ish Chai? How does Chabad hold for the Polar zmanim?

That's an interesting one. Seems like most (although certainly not all) Chabad Rabonim go L'Chumra for both so they probably told you to keep Shabbos from Shkia Hanireis until Alos as well as by polar Zmanim if that's an option. (If that even makes sense. I'm not so well versed in polar Zmanim.)

[Dan]

Good point. Obviously t's by degrees and would change by location. My research was done for 11213.That's an interesting one. Seems like most (although certainly not all) Chabad Rabonim go L'Chumra for both so they probably told you to keep Shabbos from Shkia Hanireis until Alos as well as by polar Zmanim if that's an option. (If that even makes sense. I'm not so well versed in polar Zmanim.)

Mostly correct and that was the general consensus as compiled by @dirah and the psak I got from my Rov. But some Rabbonim abstained or said not to go based on the chumra possibly being keeping polar zmanim lchumra.

[MeirS]

It's interesting that most complications in planning in flight Zmanim are only about figuring out your precise latitude and longitude but once you have that, finding the Zmanim are (relatively) easy.
In your case, finding the exact location was simple, figuring the Zmanim for that location was the complicated part.

[Dan]

It's interesting that most complications in planning in flight Zmanim are only about figuring out your precise latitude and longitude but once you have that, finding the Zmanim are (relatively) easy.
In your case, finding the exact location was simple, figuring the Zmanim for that location was the complicated part.

When we were planning the trip we were under the impression there would be no WiFi, would make things complicated. With WiFi my job was a lot easier.

[Dan]

The story of the Alter Rebbe stopping the boat came up in regards to a shayla I asked about Kiddush Levana and I spoke about it during our Shabbos meal as a potential reason for the diversion which ensured we wouldn't make it to an area where there would be a question in what the Alter Rebbe might pasken.

@Something Fishy then informed me if I told the story one more time I would be fed to the penguins.

[MeirS]

For our purposes, the consensus from nearly everyone is that Shabbos starts at Shkia and ends at Alos on Sunday.

Why not till Chatzos according to the AR if the sun doesn't go much below the horizon?

[MeirS]

The story of the Alter Rebbe stopping the boat came up in regards to a shayla I asked about Kiddush Levana and I spoke about it as a potential reason for the diversion which ensured we wouldn't make it to an area where there would be a question in what the Alter Rebbe might pasken.

@Something Fishy then informed me if I told the story one more time I would be fed to the penguins.

[Dan]

Why not till Chatzos according to the AR if the sun doesn't go much below the horizon?

Where we were, Chatzos=Alos=Misheyakir

[Something Fishy]

The story of the Alter Rebbe stopping the boat came up in regards to a shayla I asked about Kiddush Levana and I spoke about it during our Shabbos meal as a potential reason for the diversion which ensured we wouldn't make it to an area where there would be a question in what the Alter Rebbe might pasken.

@Something Fishy then informed me if I told the story one more time I would be fed to the penguins.

I am hereby resigning my post as mod.

[MeirS]

I am hereby resigning my post as mod.

@Dan can no longer threaten to feed you to the penguins.

[aygart]

I can write a book on the research I did into the sunset issues.

THen you should.

[Dan]

I am hereby resigning my post as mod.

Bing Bong
Wonderful good afternoon, lunchtime is well underway in the restaurant and the bistro. Enjoy your lovely lunch and I wish you a bon appetit. And for your reading pleasure:
https://www.chabad.org/kabbalah/article_cdo/aid/380178/jewish/The-Moon-Over-the-River.htm

[Dan]

THen you should.

@dirah would do a far better job than me. A real zmanim expert and very knowledgeable of all of the dayos.

[aygart]

@dirah would do a far better job than me. A real zmanim expert and very knowledgeable of all of the dayos.

It is an opportunity for you!

[Dan]

Good point. Obviously t's by degrees and would change by location. My research was done for 11213.That's an interesting one. Seems like most (although certainly not all) Chabad Rabonim go L'Chumra for both so they probably told you to keep Shabbos from Shkia Hanireis until Alos as well as by polar Zmanim if that's an option. (If that even makes sense. I'm not so well versed in polar Zmanim.)

For example, here are the zmanim for Port Lockroy, Antarctica, with Shkia (Haniris) and Shkia Amitis zmanim enabled:

https://www.chabad.org/calendar/zmanim_cdo/aid/143790/jewish/Zmanim-Halachic-Times.htm#additional=true&bdef=0&before=18&coords=-64.8251,-63.4947&locationType=3&n=Port%20Lockroy&tdate=12/15/2018&tzname=America/Argentina/La_Rioja

We kept Shkia Haniris and Shkia Amitis L'chumra.

That's about as far south as made it.

Had we made it down to -65.12, we would have lost shkia amitis calculations:
https://www.chabad.org/calendar/zmanim_cdo/aid/143790/jewish/Zmanim-Halachic-Times.htm#additional=true&bdef=0&before=18&coords=-65.12,-63.4947&locationType=3&n=65.12&tdate=12/15/2018&tzname=America/Argentina/La_Rioja

At -65.87 we would have lost all shika calculations:
https://www.chabad.org/calendar/zmanim_cdo/aid/143790/jewish/Zmanim-Halachic-Times.htm#additional=true&bdef=0&before=18&coords=-65.87,-63.4947&locationType=3&n=65.87&tdate=12/15/2018&tzname=America/Argentina/La_Rioja

[MeirS]

For example, here are the zmanim for Port Lockroy, Antarctica, with Shkia (Haniris) and Shkia Amitis zmanim enabled:

https://www.chabad.org/calendar/zmanim_cdo/aid/143790/jewish/Zmanim-Halachic-Times.htm#additional=true&bdef=0&before=18&coords=-64.8251,-63.4947&locationType=3&n=Port%20Lockroy&tdate=12/15/2018&tzname=America/Argentina/La_Rioja

We kept Shkia Haniris and Shkia Amitis L'chumra.

That's about as far south as made it.

Had we made it down to -65.12, we would have lost shkia amitis calculations:
https://www.chabad.org/calendar/zmanim_cdo/aid/143790/jewish/Zmanim-Halachic-Times.htm#additional=true&bdef=0&before=18&coords=-65.12,-63.4947&locationType=3&n=65.12&tdate=12/15/2018&tzname=America/Argentina/La_Rioja

At -65.87 we would have lost all shika calculations:
https://www.chabad.org/calendar/zmanim_cdo/aid/143790/jewish/Zmanim-Halachic-Times.htm#additional=true&bdef=0&before=18&coords=-65.87,-63.4947&locationType=3&n=65.87&tdate=12/15/2018&tzname=America/Argentina/La_Rioja

It's interesting how in a location where there is הנץ הנראית but no הנץ האמיתי, Sof Zman Krias Shema Shel Shachris (AR default) is the same as תחילת זמן קריאת שמע של ערבית.

It's also interesting to note that in the 3rd location you posted, on Shabbos there is a sunrise (since the sun set the evening before) but no sunset (and no sunrise on Sunday).

[Dan]

It's interesting how in a location where there is הנץ הנראית but no הנץ האמיתי, Sof Zman Krias Shema Shel Shachris (AR default) is the same as תחילת זמן קריאת שמע של ערבית.

It's also interesting to note that in the 3rd location you posted, on Shabbos there is a sunrise (since the sun set the evening before) but no sunset (and no sunrise on Sunday).

Not all of the zmanim make sense. For example even if you held Rabbeinu Tam 72 minutes, you wouldn't actually wait until after Alos Sunday for Shabbos to be over.

[jose34]

Lot's of us, me included are interested in reading up on this fascinating halachic discussion.

+100;

@Dan thanks for the bit on insight if someone can write up more on this it would be amazing.

Also I did not read through the whole thing but for further reading on this topic there an journal article by Rabbi David Bleich:
http://traditionarchive.org/news/originals/Volume%2036/No.%203/Survey%20of%20Recent.pdf

[Naftali]

Lot's of us, me included are interested in reading up on this fascinating halachic discussion.

For English Articles:

(1)   See the aforementioned article by R’ JD Bleich published in Tradition (http://traditionarchive.org/news/originals/Volume%2036/No.%203/Survey%20of%20Recent.pdf). See also the letter from Cyril Domb regarding R’ Goren opinion, and R’ Bleich’s response here: http://traditionarchive.org/news/originals/Volume%2037/No.%202/Communications.pdf
(2)   Here is the article that most easily shows up in the world of google scholarship: https://www.star-k.org/articles/kashrus-kurrents/515/when-does-one-pray-when-there-is-no-day/. For anyone interested, here is the more comprehsnive version that R’ Heber wrote in his Hebrew language Sefer: http://hebrewbooks.org/pdfpager.aspx?req=53000&st=&pgnum=107
(3)   Another more simple read: http://dinonline.org/2012/06/03/halacha-talk-the-exotic-traveler/
(4)   The following is not an orthodox source but quotes an array of sources, including the opinion of the Lubavitcher Rebbe. http://www.schechter.edu/a-responsum-regarding-space-travel/. He cited the Lubavitcher Rebbe in “Yagdil Torah, New York, 1981, No. 73.” I have not been able to locate this source.

Hebrew Articles and Resources:
(1)   R’ Boruch Simon source compilation on the topic: https://www.yutorah.org/download.cfm?materialID=517617 (this includes the article from R’ Kasher, Minchas Elazar, R’ Posen. Another compilation of Hebrew sources: http://beinenu.com/system/files/alonim/124_o.pdf?download=1 
(2)   R’ Taplin: תאריך ישראל עמוד תתמט (Can’t seem to find it online aside from Otzar Hachochma).


Between these sources, one will see addressed in regards to keeping shabbos:
(1) The preliminary question of whether the halakhic “day” requires a sunrise & sunset or a 24 hours (just about) period constitutes a day – this is largely based on proofs from Tanach, Gemaras, Midrashim (significantly a Pirkei D’Rav Elazar),
(2) Assuming a sunrise & sunset is required, is shabbos really every seven years!?!?,
(3) Assuming sunset & sunrise is not required to constitute a halakhic day (either on a d’orysa, or at least d’raban level [meaning, perhaps Shabbos on a d’orysa level is every seven years but to not “forget Shabbos” it should be kept on a rabbinic level every seven days – a similar, though not exact notion is noted when one is lost in a desert], what time does Shabbos begin or end:
(i) place where one left from [very ambiguous standard, what “place”],
(ii) lowest point of the sun is sunset, highest is sunrise (odd because lowest point is the sun’s general revolution (aka earth’s revolution) is chatzos, not sunset,
(iii) highest and lowest points of the sun are chatzos hayom and Layla, 12 hours in between each, six hours before highest point is sunrise, six hours later is sunset,
(iv) use the sunset/sunrise of the same longitude,
(v)  Just use Israel zmanim (Jerusalem?).

Note A: These times help for actual sunset (shkia); how to calculate tzeis, if there is a tzeis, may be harder. If ppl like using the somewhat arbitrary 60 (?), slightly less arbitrary 72 (or 90 !?!) this may get more complicated as to what makes sense.  If Tzeis is amount of degrees below the horizon, then it should be easy to figure out (relatively I guess) based on the sun’s descend from the mid-point from highest to lowest (after hour six) the generally assumed proper degrees.

Note B: These times are to figure out the halakhic day which relates most significantly to Shabbos. There are other questions (i.e. Krias Shema) which may require a separate analysis because these may require a halakhic “Layla/night” which would not exist when there is daylight all 24 hours (and vice versa in the winter) – see Rabbi Shternbuch in the quotes מועדים וזמנים who makes this salient point. Or perhaps because Shema is not a “night” based on mitzvah but a “sleeping/awaking” based on mitzah it will apply and be even less complicated than Shabbos question.

ותן לחכם ויחכם עוד.

[yesitsme]

Could you please move it to zmanim thread, I get excited every time I see a new post only to find some zmanim talk . @Something Fishy pass it on to current mod thanks.