Shabbat (and other times) on Mars

[cellio]

I was recently asked about this, and I don't know what the current thinking is.

The question of when an astronaut observes Shabbat (while in space) is well-understood. [1] But what happens when we colonize other planets and your hometown is on Mars? Do you count six Mars-days and observe the seventh as Shabbat? How long is a month (and how do you decide which moon)? Is it still desirable to stay in sync with Earthly seasons, or will that go out the window? If you follow the sun as locally experienced, what happens when that causes hardship? (Does the lunar colony observe one ~29-day Shabbat every seven months?) There must be commentary on this by now from sources other than Wandering Stars, but I don't know what the popular opinion is.

[1] I know of three opinions for the astronaut in space: follow your hometown, follow the city from which you launched (your port of departure, like for ships), or follow Jerusalem. All of these involve a ~25-hour Shabbat every seven days, like on Earth, even though your orbit might cause you to see a 90-minute day. But the astronaut is, by definition, just visiting.

Comments

[geekosaur]

Also, what direction do the shuls point? Especially considering that (a) Earth could be at any angle within 4π steradians, and (b) the angle will probably change over centuries.

[cellio]

Up? :-)

I don't know. Would someone establish a "local" (planetary) proxy for Jerusalem and say "point here"? Or would the custom fade?

[geekosaur]

Quite possibly the custom would fade, if I'm remembering correctly about it being recent. After all, the Sages already have an all-purpose fallback: "direct your heart (to pray) toward Jerusalem", even if you don't know what physical direction it's in.

[chaos-wrangler.livejournal.com]

My dad used to point out that in the 4 or so rooms in a local shul that were used regularly for minyanim, only the beginners' minyan faced east. All the minyanim faced towards their respective arks, but the choice of location for each ark was based on room/building architecture more than anything else.

[geekosaur]

I have a recollection of hearing on KMTT that the whole thing about shuls pointing east, or more correctly toward Jerusalem, is actually a fairly recent conceit — only a couple hundred years old.