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NASA wants to create a time zone on the moon. Here’s what that means for Jewish space travelers

When Shabbat and the holidays begin and end are by no means the most important questions. It’s deeper than that

“When does Shabbat start on the moon?”

People ask me this question a lot, and I don’t even live there. As someone who writes about Judaism and technology, and who wrote an entire dissertation on the history of Jewish timekeeping, it’s the sort of question that seems to waft toward me at conferences, meals, and whenever something even vaguely adjacent shows up in the news.

The last of these is the reason I’m writing this now: NASA has decided that the moon needs its own timekeeping system, and so the inevitable speculation about how the moon’s nonexistent Jewish residents will pray, light Shabbat candles, and observe the festivals has once again resumed.

The question is supposedly interesting because the Jewish calendar, like all calendars, is beholden to the sun, and the sun appears and disappears at unusual times when you’re not on Earth. An astronaut on the International Space Station will see the sun rise and set 16 times every day, while a moon resident will go two weeks before seeing either one.

Hearing this, students of Jewish law perk up their ears. How interesting, they enthuse. Perhaps an observant astronaut on the ISS will need to pray three times every 90 minutes, keeping Shabbat once every ten hours! Perhaps the lunar Shabbat lasts for an entire month! Or perhaps we will all simply defer to an Earth location, like Cape Canaveral (the site of many rocket launches) or Jerusalem? How fascinating. What a nice, low-stakes question into which we can sink our teeth. What do you think?

I’ll tell you, though I don’t offer this response in polite company. My answer is: I don’t know and neither does anyone else, so please stop asking this bad and inane question because it is getting in the way of better and smarter questions, and it makes the Jewish religion sound small-minded to boot. Along with Mel Brooks’ Jews in Space bit, this question desperately needs to be retired as a go-to paradigm for extraterrestrial Judaism. Put away your calculator. Let’s think about this a different way.

Time, and space … and dreidels

Judaism is bound by laws, but no law is perfect. Prayer times were designed to fit into the natural rhythms of the day, but the day was a lot easier to regulate for the rabbis of the Talmud, who lived at more moderate latitudes where the length of the day doesn’t change that much between summer and winter. Forget about living on the moon: The rabbis who wrote these laws weren’t even thinking about living in London, where the technical start and end of the day are regularly out of whack with the way that most people spend their days. This is a design flaw, and despite some workarounds (like starting Shabbat early in the summer), it has never been fully resolved.

Let’s not feel too bad about this. Jews were certainly not the only ones who struggled to legislate for the full globe. When the medieval Muslim traveler Ibn Fadlan met a muezzin (a person who proclaims the call to prayer) in Viking territory, the man complained to him that the gap between the last prayer of the night and the first prayer of the morning was not even long enough to boil a kettle of water, and that he was constantly afraid of “oversleeping,” forgetting to call out prayer times. It makes sense that Muslim scholars didn’t account for the poor man: Many medieval geographers weren’t convinced that those northerly latitudes were even habitable.

When clock time falls out of step with the needs of the human body and mind, it begins to feel oppressive. A Roman playwright, writing not long after the 24-hour day was implemented, seethed that the gods should destroy “that man who first discovered hours and who first set up a sundial here” — because these just get in the way of “my stomach, by far the best and truest of all clocks.”

We accept formal timekeeping because it keeps the trains running, but we lose our way when we treat it like an immutable law to which all else must bend. Tell a prospective astronaut that they must pray 48 times a day and they either won’t listen to you or they won’t become an astronaut. Tell a prospective lunar resident that they must keep Shabbat and the holidays according to Jerusalem time and they may question your fixation on a city that they’ve probably never visited.

I’ve consumed a lot of science fiction in my life, and the fact that extraterrestrial prayer times feature in approximately zero stories tells you that the solutions are less interesting than the question — or that the people who got stuck on the question got left back on Earth. While important discussions about Jews in space do exist — Menachem Kasher’s 1969 essays on the Apollo program are still worth reading — their value is largely for people who dream about going to space, not the ones who actually go there. Honestly, it’s better if you don’t tell astronauts anything at all. This is a time for listening.

Consider what timekeeping could mean for an astronaut. Beyond giving expression to human and celestial rhythms and enabling coordination, timekeeping is an expression of values and sometimes an assertion of political control. Long ago Jacques Le Goff argued that the mechanical clock secularized time by allowing time to be separated from the church.

In science fiction, humans on ships or other worlds will frequently invent new systems that center their unique experiences and form bridges between their needs and the cycles of their surroundings. In Kim Stanley Robinson’s Mars trilogy, the planet’s slightly longer day — 24 hours and 39 minutes — leads to a ritual when clocks literally stop for the surplus, creating a Shabbat-like miniature palace in time of which Rabbi Abraham Joshua Heschel certainly would have approved.

This doesn’t mean that Jewish law has nothing to contribute. Frank Herbert, Isaac Asimov, and many other giants of science fiction assumed that future humans would forget their origins. Maintaining some links to Earth time — perhaps through the conservation of Rosh Chodesh (the first day of a Jewish month), which links the Earth and its moon — holds the door open for a spacefaring culture that remembers our terraqueous globe, much as diaspora Jews use a liturgy that is deferential to Israel’s agricultural cycles. If Jewish futurism is defined by its desire to be fully in conversation with our entire past, then these knowingly obsolete rituals could become the pillars of interstellar Judaism.

But let’s not rush things. While the 19 Jews who have been to space make the group significantly overrepresented among the 600-odd people who have been there — more Jews have been to space than Muslims — 19 is still a very small number and space Jews aren’t selected for their interest in Jewish law. The difficulty and expense of space travel mean that technical ability will be prioritized over creative brilliance for the foreseeable future, so the astronauts who set precedent will likely be extremely pragmatic about their choices.

It will likely be many decades before this laity is joined by a rabbi of any sort of denomination, and the Jewish culture they find there will be unlike anything from Earth. Consider that the dreidel set in motion this past December was spun by Jasmin Moghbeli, a Lutheran with a Jewish husband who celebrates both Jewish and Christian holidays. (Her kids sent her up with a paper menorah since, you know, open flames and space stations do not mix).

There is every reason to think that space Judaism will be a weird, syncretic slurry of adapted ideas. Rather than mechanically launching our earthbound timekeeping into orbit, we should take a step back and understand the needs of the brave human beings who are forging a path among the stars. There’s no better way to prepare our terrestrial faith for its next journey.

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