As many of you know by now, November 28, 2013, will be both (American) Thanksgiving and the 1st day of Chanukah! The possibilities are endless: deep-fried turkey; latkes with cranberry sauce and gravy; pumpkin sufganiot; I’m sure you have more in mind. This week an article by Jonathan Mizrahi on this calendar issue has been making the rounds. It has some excellent graphs illustrating both the rarity of Thanksgivukkah in our present era and the long-term drift of the calendar that will make Thanksgivukkah impossible in the future, but it somewhat overstates its primary claim that Chanukah and Thanksgiving are “a once in eternity overlap”. This FAQ answers some questions that this article has inspired in various other forums, and corrects a few nuances.
Many thanks to Stephen P. Morse for creating an excellent tool to answer calendar questions quickly (though if he’s reading this, I’d love to see the capability of going beyond 9999 CE, and of distinguishing between Adar and Adar I), and to Remy Landau for providing the raw data on the Rosh Hashanah drift (though if he’s reading this, what’s with the popup ads?).
If you have questions that aren’t answered here, we’ll try to answer them in the comments (and if there are a lot, we’ll put together a sequel).
1. What is causing the long-term drift in the calendar?
You’ll notice from Mizrahi’s graph that the Jewish holidays shift significantly from one year to the next (like seasonal variations in the weather), but also (on average) slowly drift later over long time periods (like climate change). The year-to-year shifts are because the Hebrew calendar is primarily a lunar calendar, and 12 lunar months are approximately 354 days – much shorter than the solar year of ~365.25 days. Without any correction, the Jewish holidays would continue to move ~11 days earlier every year. (This is what happens with the Islamic calendar, in which every year is 12 lunar months without exception, so over several decades the Muslim holidays traverse the entire solar year.) In order to keep the Jewish holidays roughly aligned with the solar year (so that Pesach is always in spring, etc.), an month is added every few years, so Jewish “leap years” have 13 lunar months instead. As the Greek astronomer Meton discovered, 235 lunar months (=19*12 + 7) are approximately equal to 19 solar years, so if we put the calendar on a 19-year cycle, and add an extra month to 7 out of every 19 years, it mostly works out.
BUT NOT EXACTLY. 235 lunar months add up to 6939 days 16 hours 595 parts. (In Jewish calendar math, “parts” are the basic subdivisions of an hour, instead of minutes and seconds. There are 1080 parts in an hour, so 595 parts is about 33 minutes.) In the Gregorian calendar, 19 solar years (on average) are 6939 days 14 hours 626 parts. That’s about a 2-hour difference. So the Jewish holidays (on average) shift about 2 hours later during each 19-year cycle, which adds up to a full day every 231 years.
2. Is this an issue of Julian vs. Gregorian calendars?
Not really. 19 Julian years (on average) are 6939 days 18 hours. So if the Gregorian calendar is closest to the actual solar year, the Jewish calendar is doing better than the Julian calendar at approximating it (but still not well enough). (Think of it this way: By definition, the Julian calendar deviates from the Gregorian calendar by 3 days every 400 years. The Jewish calendar deviates by slightly less than 2 days in the same time period.)
3. But there’s some mechanism in place to correct this drift before it gets out of hand, right?
Nope. If no action is taken, the Jewish calendar will continue to drift later and later, until Pesach is in summer, Rosh Hashanah is in winter, etc. And it’s not clear how any action could be taken, since there’s no Jewish pope or Sanhedrin or any sort of body empowered to act on behalf of the whole Jewish people. But on the bright side, (as Mizrahi mentions) if we wait tens of thousands of years, we’ll loop all the way around to where we started.
The Catholics do have a pope, and so even though Easter is on a similar 19-year cycle, they’ve instituted corrections to keep it from drifting. Easter and Pesach usually coincide, but in the years when they’re a month apart instead, let’s just say it’s not Easter’s fault. More »
So far, Nobel week 2011 has been Good For The Jews, with Jewish scientists among the winners in 3 out of 3 prizes. Following Beutler and Steinman on Monday in Medicine, and Perlmutter and Riess yesterday in Physics, today’s winner in Chemistry is the Israeli materials scientist Dan Shechtman of the Technion. This is Israel’s second chemistry prize in 3 years; Shechtman follows Ada Yonath of the Weizmann Institute, who won in 2009 for her work on the structure of the ribosome.
What did Shechtman win for? He revolutionized the field of crystallography by discovering quasicrystals, crystals whose atoms form a pattern that never repeats. The story of the discovery is pretty amazing; I recommend reading the whole thing from the Nobel website.
An excerpt:
When Shechtman told scientists about his discovery, he was faced with complete opposition, and some colleagues even resorted to ridicule. … The head of the laboratory gave him a textbook of crystallography and suggested he should read it. Shechtman, of course, already knew what it said but trusted his experiments more than the textbook. All the commotion finally led his boss to ask him to leave the research group, as Schechtman himself recalled later. The situation had become too embarrassing.
In the coming days, we’ll see whether the sweep holds up for Literature, Peace, and Economics.
Mazal tov to Saul Perlmutter (Lawrence Berkeley National Laboratory), Brian Schmidt (Australian National University), and Adam Riess (Johns Hopkins University; Space Telescope Science Institute) for winning the 2011 Nobel Prize in Physics for their discovery that the universe is not only expanding, but accelerating!
Apart from the Woody Allen clip, why is this story on Jewschool? Because Perlmutter and Riess are both Jewish! They are the first Jews to be awarded a Nobel Prize since… yesterday, when Bruce Beutler and Ralph Steinman z”l won the Nobel Prize in Medicine (along with Jules Hoffmann) for their work in immunology. They are also the first Jewish physics laureates since Roy Glauber in 2005. More »
My first year at camp as a kid was great: Sports, Arts and Crafts, Lake Front, Advanced Swimming and, of course, the coveted first dance with a girl. All of this was set against the bucolic setting of the NJ-YMHA-YWHA Jr. camp, Camp Nah-Jee-Wah. Two years later I would be off to California with my family but Camp Nah-Jee-Wah has always held a special place in my heart and so did that dance with Rachel Cohen-Stien-Berg-Steen (clearly it was much more important at the time).
All kidding aside, Jewish summer camp changed my life for the better. I learned more in five years as a camper at Camp Alonim than I did in more than a decade of religious school. I met my wife and a number of our lifelong friends at Greene Family Camp. I went into Jewish Community Work all because of the things that happened to me at camps.
The most important thing I learned at these camps besides being one of the best sports players at a Jewish summer camp really isn’t so impressive when you come back home, was that our traditions teach us to respect ourselves, our bunkmates and camp, to stick by our bunkmates when they sneak out at night and get caught and that if you kill it you fill it. Take these concepts to a more mature conclusion and you get respect for sanctity of life and environment and the importance of sticking to our values in the face of hardship (and really if you kill it you better fill it, I love the tater tots).
So when I read in the Forward this week that New Jersey’s YMHA-YWHA Camps have leased their land for hydraulic fracturing a little piece of my childhood became filled with carcinogenic waste, naturally occurring radioactive materials and devastated shale. More »
Jewish Week reports on the growing phenomenon of Modern Orthodox teens keeping ‘Half Shabbos’ and texting on Shabbat both in private and also in full view of peers and event adults.
The article does note that the phase seems to end when many teens return from gap year in Israel when they frum out. I guess between episodes of getting blotto and into trouble, they wander into the wrong neighborhood on Shabbos, texting blithely away and get violently assault. Welcome to Mea Shearim… Frum satire also fisks…
by Kung Fu Jew [➚] · Tuesday, September 21st, 2010
Since the explosion of GoogleMaps mashups nearly four years ago, Israeli-Palestinian conflict nerds like me have dreamed of seeing the settlements and sundry occupation data applied in such a visual manner. Most American Jews are idiots when it comes to the basic facts about the conflict because they have a pathetic grasp of the simple geography. Forgive my blunt assertion, but even most Israelis are blithely clueless about where even the Green Line runs.
Now behold! Americans for Peace Now releases much of that database, combined with their own copious Settlement Watch research, in “Facts on the Ground” — also available as an iPhone app! Take a tour via my screencast below:
Abraham Lincoln didn’t go to services on Rosh Hashanah.
But on this Rosh Hashanah, Rosh Hashanah 2010, we are asking to be written in the book of life and entering the ten days of teshuvah at a time when our online lives are so intertwined with our real lives that the structure of the world online is inevitably a part of these holy processes. Even though history might be different if Lincoln hadn’t let John Wilkes Booth know where he was by checking into Ford’s Theatre on foursquare that fateful night in 1865, good ole Honest Abe has some useful things as we renew ourselves in a more connected and searchable world.
In December 1862, one month before signing the Emancipation Proclamation, Lincoln spent days toiling over a message to Congress. The concluding paragraph is a rousing call.
“The dogmas of the quiet past, are inadequate to the stormy present. The occasion is piled high with difficulty, and we must rise — with the occasion. As our case is new, so we must think anew, and act anew. We must disenthrall ourselves, and then we shall save our country.” -Abraham Lincoln
Now the theme of emancipation is one that we as Jews are familiar with. But Lincoln’s message highlights an important aspect of emancipation that is often overlooked. Emancipation is not just about justice for slaves. As Lincoln says, we must rise to the challenges of our times, and these challenges require us to think and to act in new ways. How can we think and act in new ways if we are stuck in the same social roles that we have inhabited our whole lives? Stuck in roles that we may have even inherited from our parents or even grandparents. Master and slave, employer and employee, rich and poor. The problem with persistent, generationally inherited inequality is not only the injustice for those who get the short end of the stick. It is the erosion of a society’s ability to rise to the occasion when it is piled high with difficulty. How can you think anew and act anew when your role in the world is entirely defined by your past? How can you think in new ways when the world is constantly adapting itself to fit your old ways? More »
Mazal tov to Prof. Elon Lindenstrauss of Hebrew University and Princeton University, who just became the first Israeli to win the Fields Medal! The Fields Medal, awarded this week in India at the International Congress of Mathematicians, is often called the Nobel Prize of mathematics (there is no Nobel in math), but unlike the Nobel Prizes, it is only awarded every 4 years, and only to people age 40 and under.
Lindenstrauss won the prize “for his results on measure rigidity in ergodic theory, and their applications to number theory”. “Er-WHAT-ic theory?”, you may ask. The official release explains:
Richard Silverstein is one of my favorite writers on Israel-Palestine. He’s a principled liberal with an eye for political realities, and an unwavering dedication to peace. He tends to be one of the best at cutting through whatever the day’s talking points and divisive arguments are (from both the right and the left) and really getting to the heart of matters. And he’s superb at contextualizing current events in terms of the larger political and cultural struggle for peace.
I kid you not, the best that the brightest minds behind the Israel lobby could devise in preparation for Mahmoud Ahmadinejad’s upcoming appearance at the UN in New York is taking out this full-page ad in the N.Y. Times, costing hundreds of thousands of dollars, and saying the way to stop Iran’s ‘unquenchable thirst’ for nuclear weapons is to stop using oil.
I agree with Silverstein that Iran is too often used by Israel apologists as a distraction from more pressing issues, and I too resent the tendency of the organizations behind this ad (according to Silverstein they include AIPAC, the ADL, B’nai Brith, and others) to paint complicated issues as simple goodguys-vs.-badguys scenarios, but criticizing someone who advocates energy independence puts you in a tricky position. Silverstein does address this near the beginning of his post:
Well, OK, not all oil, we can keep guzzling good ol’ U.S. crude, but “foreign” oil is bad.
He’s definitely hitting the nail on the head here: focusing only on foreign oil dependence tends to refocus the debate on energy instead of climate change (which in my opinion is the wrong focus). That being said, anyone paying any attention to the domestic political discourse on climate change knows that some of our strongest allies are the guys with national security credentials and the businesspeople. The former are already on board; the challenge now is wooing the latter. The tripartisan (it is ridiculous that that is even a term) climate bill that was supposed to be introduced last week made some pretty excellent progress on this, but it’s slow going. For some inspiration, here’s what Thomas Friedman thinks Obama should say:
“Yes, if we pass this energy legislation, a small price on carbon will likely show up on your gasoline or electricity bill. I’m not going to lie. But it is an investment that will pay off in so many ways. It will spur innovation in energy efficiency that will actually lower the total amount you pay for driving, heating or cooling. It will reduce carbon pollution in the air we breathe and make us healthier as a country. It will reduce the money we are sending to nations that crush democracy and promote intolerance. It will strengthen the dollar. It will make us more energy secure, environmentally secure and strategically secure. Sure, our opponents will scream ‘carbon tax!’ Well, what do you think you’re paying now to OPEC? The only difference between me and my opponents is that I want to keep any revenue we generate here to build American schools, American highways, American high-speed rail, American research labs and American economic strength. It’s just a little tick I have: I like to see our spending build our country. They don’t care. They are perfectly happy to see all the money you spend to fill your tank or heat your home go overseas, so we end up funding both sides in the war on terrorism — our military and their extremists.”
Climate change is as much, if not more, of a threat to our national security as the Israeli-Palestinian conflict. The two issues make for strange bedfellows, to be sure. But right now we need more bedfellows, not less. These are global problems, and if takes the whole globe in bed together to find solutions, then so be it.
Upon setting out to write this dvar Torah, I had grand visions of talking about the halakhic status of coed toilets. If a woman is ritually unclean, how can other members of her family use the same toilet, for example?
There was going to be a blow-out Foucauldian analysis of the halakhic sources, followed by a lengthy exegesis on Melanie Klein’s partial object; Kohut’s narcissistic transference, and Freud’s paranoia “syllogism” as taken up by Lacan. And then the ground-breaking revelation that we have been/are currently/always will be sinning.
It was going to be fabulous.
Perhaps fortunately for you, Masechet Niddah, Masechet Khullin, and Masechet Keilim (11:2) took me to school. Once again. We can use the same toilet as someone who is ritually unclean because the toilet is “מחובר לקרקע” (it is connected to the ground)—this is the loophole. (For those following at home, this is the same term used in reference to mikvaot, or ritual bath pools.) Furthermore, I learned that in our times–i.e. post-Temple times–we are all tamei met already, and thus this is a non-issue.
Now that we’re all breathing comfortably…
I will tell you, instead, about how I first learned about sex. (What does this have to do with tazria metzorah, you ask? Just wait. You’ll see.) More »
Just when you thought you’ve seen every kitsch Passover-related item this year, here is one more from across the pond. At first I thought it was a farce, but the prices at the bottom of the screen make me inclined to believe that this is indeed a real product available for sale. What’s more, this dude has a pretty wicked accent. 90 NIS to anyone who correctly identifies where he’s from.
For the benefit of those who don’t speak Hebrew, I am including below a transcript of this ad so you can follow along:
The Ravco Company presents: The Redemptive Reclining Device
When the night of the Seder arrives, we, along with our whole family, gather around the table. We are obligated to drink four cups of wine; we are obligated to eat matzah; we are obligated to eat korech–and all of this while reclining. And also the afikomen! How can one do this correctly? How can one do this without disturbing others? Without spilling wine on the person next to you? How can you eat matzah without dropping crumbs all over the floor?
I’ve always had a problem. You can’t lean on the table, and leaning back on the chair is really uncomfortable. It hurts my whole body!!!
This year, there is a solution: The Redemptive Reclining Device! One click and you connect to any chair or seat, allowing you to recline in complete perfection. A mechayeh!
South by Southwest is an annual music, film and interactive media festival/conference that descends upon my (David AM Wilensky’s) hometown of Austin, TX every March. Yesterday, my mother, Glenda S. McKinney, attended the Judaism 2.0 session of SXSW Interactive.
She is a great Jewish mother and tweets as @gsmaustin. What follows are her tweets and notes from the session.
The Judaism 2.0 session at SXSW Interactive was live streamed, and the video is available at here.
At about 6:30, there’s a pan of the room, so you can see the original group of about 40 in addition to the 20+ sites that were live streaming. The introductions are pretty much unintelligible, but it was a good mix of people: Jews and non-Jews, several Austinites and a few Israelis, active bloggers, and Jewschool founder Dan Sieradski.
Dave Weinberg @weinberg81 announced a conference on the future of Jewish non-profits that will be held in July 29 at the 92nd Street Y in New York City: bit.ly/fojnp. He did ParnasaFest parnasafest.org/.
Chaviva said that there is no funding to do the decennial census of the US Jewish population, and talked about work she did to gather contact information for congregations and federations to try to do an informal census. At around 30:00, this went into a discussion of congregations not being active on the internet, and privacy and security concerns.
Dan Sieradski talked about using technology to interact differently with Judaism: build alternative communities on-line, open source Judaism, build your own Haggadah, BBYO’s build-a-prayer site, and JPS Tagged Tanakh. A few people talked about using Second Life to do Jewish things, like visiting the Wall and attending Torah study or services. (So I could ‘really’ go to the Wall, virtually.) You can tweet to @kotel to have your message inserted into the Wall. Mordechai talked about people discussing Daf Yomi via Twitter.
The best part came towards the end, which was planning for next year Apparently, there was some resistance to having this session at SXSW–because there was a fear that it might be religious in nature–so we talked about what we’d like to see in the future, where it could happen, who could do it, etc.
Intersections of Jewish interest with the larger group, like moderating hate speech, were proposed as possible topics that might be more easily accepted as sessions.
There was talk of having Israeli start-ups and tech companies at the conference, just as there are booths for the West Midlands of England and for Finland. The Cleanovation event by the Texas-Israel Chamber of Commerce in Austin earlier in March and Austin’s Blue Knot group were talked about as possible models and resources.
As a final editorial note of bizarreness, as the session wrapped up, I was sitting on a train on my way to Taste of Limmud NY when I recieved the following tweet from Dan: “mobius1ski: @davidamwilensky I just met your mom.”
There are ways to support human rights in Iran with advocating for neither shock and awe nor estrangulation of civilians. In Congress now are two brilliant bills supported by Americans for Peace Now which help human rights activists in Iran:
HR 4301 – the Iran Digital Enhancement Act (IDEA) would help give the Iranian people the high-tech tools they need to communicate online. It would also make it harder for the Iranian government to monitor or block Internet communications.
HR 4303 – the Stand with the Iranian People Act (SWIPA) would punish corporations that help the Iranian government stifle free speech. It would also allow American nonprofits to provide humanitarian aid within Iran. And it would bar Iranian officials who have abused the human rights of the Iranian public from entering the United States.
Presently it is illegal for American companies to do business in Iran — including Twitter, Facebook, and the tools used by the Green movement activists to bypass the Iranian government’s stifling media control. More »
This weekend, Pope Benedict XVI voiced concern over the use of those creepy full body scanners at airports. He’s against them, saying “the primary asset to be safeguarded and treasured is the person, in his or her integrity.” The Pope continued:
Respect for the principles he enunciated “might seem particularly complex and difficult in the present context”, he told his audience, which included airport managers, airline executives, security workers, pilots, cabin and ground staff.
They had to contend with problems arising “from the economic crisis, which is bringing about problematic effects in the civil aviation sector, and the threat of international terrorism, which is targeting airports and aircraft”. But, he warned: “It is essential never to lose sight of respect for the primacy of the person.”
The pope’s words will delight civil liberties campaigners opposed to a device that strips passengers virtually naked.
He’s only a few weeks behind various Islamic authorities, who have come out against the scanners. Fiqh Council of North America issued a fatwah statement as passing through the scanners would violate Islamic rules of modesty.
And the Jews? There seems to be (shocking, I know), differing opinions. The Rabbinical Center of Europe (an umbrella organisation for Orthodox communities) has declared the scanners to be immodest, but allowed. Part of their issue is that men should review images of men, women those of women. They were assured that images are reviewed by computer software, and humans are only involved if something is found. But this isn’t accurate. We know from many reports that the images aren’t written over or erased, that security staff are looking at images. So will rabbis in Europe reconsider? What about in North America?
Remember a year or two ago when GPS technology started being added to cell phone applications? Many of us scoffed at the idea of being trackable by Big Brother or God knows who else, imagining the worst case scenarios of a privacy-free world. Fast-forward to today, and we can’t imagine walking from the subway to a meeting at an unfamiliar location without whipping out our phone and asking Google Maps to guide us, and when the meeting is over, we ask Google Local to guide us to the closest bar with a happy hour.
Well, my friends, Augmented Reality is the next feature coming to your phones that you won’t be able to live without. At its most basic, AR technology allows you to point your phone’s camera lens at objects in the real world to conjure all sorts of information related to it on your screen. The Boston Globe had a great introduction to the technology published in September.
AR technology has many potential applications in Jewish life. The most obvious to me fall in the categories of preservation of memory. Imagine walking through a Jewish cemetery and having instant access to biographical information, photographs, videos, family trees, and more, all available on your phone simply by focusing your camera on a particular headstone. Or envision a tour through the Lower East Side where every building unlocks an oral history from the people who grew up, lived, and worked there. Or think about all those portraits hanging on your synagogue’s walls — wouldn’t it be great to hear your beloved old cantor sing once more, simply by pointing your phone at the painting of him? More »
So now, consider these six further snapshots from an internet-aware Jewish world of 2020:
#4: Surfcasting technology lets you play back a class on Jewish radicalism in which Sieradski narrates a tour of web sites on the topic. As you play the video of Sieradsky, your browser follows along and you pause to bookmark a sites on the tour. Then you copy some text to your Facebook status.
#6 An XML Jewish text specification, repository and API means that anyone who wants to download a classic Jewish text, adapt it, or reference it can do so easily. After all, Jewish classics are the property of the Jewish people, and they should be made available online.
#7 The Open Source Beit Midrash. Surfcasting meets XML Jewish text specification. An online environment where all the texts are at hand as you learn with a hevruta study partner through video chat.
#8 Jewish Book Builder. The traditional text is only the beginning of a Jewish book. The fun comes as you add commentary on the sides. Make your own Haggadah meets the Open Siddur project. Why settle for stamping your name when you can personalize a bencher for your wedding?
#9 Niggun Please is a Jewish Liturgical Music Database. Wouldn’t it be loverly if the website of your minyan, shul or school had a link to listen to the tunes and songs it uses? Imagine a playlist widget that could play a list of songs from a database of streaming niggunim — meaning Jewish liturgical tunes?
The posts are worth reading in full, as are the comments on them. Here on Jewschool, I thought I’d ask for thoughts and suggestions on making these visions a reality? How much effort and how much money will be required to make it happen? What sort of organizational structure(s)?
AR technology has many potential applications in Jewish life. The most obvious to me fall in the categories of preservation of memory. Imagine walking through a Jewish cemetery and having instant access to biographical information, photographs, videos, family trees, and more, all available on your phone simply by focusing your camera on a particular headstone. Or envision a tour through the Lower East Side where every building unlocks an oral history from the people who grew up, lived, and worked there. Or think about all those portraits hanging on your synagogue’s walls — wouldn’t it be great to hear your beloved old cantor sing once more, simply by pointing your phone at the painting of him? 
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