5 Dates You Won't Find on Your Calendar

ThinkStock/Erin McCarthy
ThinkStock/Erin McCarthy

While you may be a bit fuzzy on which months have 30 days and which have 31, it’s safe to say you’re pretty familiar with the months and days of the year. But due to unusual record-keeping practices or because of months that were eliminated over the centuries, there are a few days you’ll never see on your joke-a-day calendar.

1. JANUARY 0

At midnight every New Year’s Eve, we go from December 31 to January 1. Simple, right? That’s how it works for everyone ... except astronomers. Each year, astronomers keep track of the movements of various planets and stars, which are compiled into what’s called an ephemeris. While it’s useful for things like space travel and positioning telescopes, GPS systems also use the data to properly function.

The thing about ephemerides (the plural of ephemeris) is that they don’t reference any year other than the one for which they were written. So if you had an ephemeris for the year 2000, you wouldn’t find any mention of 1999 or 2001. Generally speaking, it shouldn’t be necessary, though, since it’s only for that particular year anyway.

Except when you referenced January 1, that is. Because some more detailed ephemerides will list the previous day’s celestial positions for reference purposes, the ephemeris would have to have information for December 31. But, since the ephemeris doesn’t refer to any other year, this date will instead often be called January 0. Going back to our year 2000 example, an ephemeris for that year might list Prince’s favorite day, December 31, 1999, as January 0, 2000 instead.

It’s worth noting that many modern day ephemerides have dropped the use of January 0 entirely, but there are others that still use it.

And back in the 1920s, several groups lobbied for a calendar with 13 months, each with four weeks. To reach 365 days, their plan was to add "January 0."

2. FEBRUARY 30

You may have a friend or relative in your life whose birthday is February 29. Maybe they fudge it and celebrate on February 28 or March 1 every year, or possibly they just have a mega-party every four years. (Or they have a mega-party every year, because why not.) So imagine how frustrating it’d be to have been born in the Swedish Empire on February 30, 1712, the only day of its kind in history.

Naturally, it was a pretty complex set of events that led to February 1712 getting two leap days. Our modern, Western calendar is called the Gregorian calendar, which was developed under Pope Gregory XIII. It’s basically just a series of improvements to the Julian calendar, created by Julius Caesar.

While the Gregorian calendar was completed in 1582, adoption by many countries was slow, so it took over 100 years for the Swedish Empire (which was primarily Protestant and not Catholic) to adopt it. Because the Julian to Gregorian swap included a difference of ten days, many regions simply skipped their calendar ahead a week and a half. The Swedish Empire decided to roll out the difference more gradually, and intended to skip leap days for forty years, starting in 1700, until the calendar was finally correct.

Except that didn’t happen because, shortly afterward, war broke out and everyone forgot about the leap days until 1712, when Sweden’s King, Charles (or Karl) XII, declared that they would forget about the Gregorian calendar and just switch back to the Julian instead. Since they did manage to skip one leap day, in 1700 (which was a leap year under the Julian calendar, but not the Gregorian), they simply decided to add it back onto the calendar that February—meaning that February 1712 had two leap days according to Sweden’s calendar, which gave them the only February 30 in history. (Sweden finally went through with the Gregorian switch in 1753 and just skipped ahead a few days, like everyone else.)

3. MARCH 0

While you could think of February 30 as some weird kind of March 0, they’re not the same thing (though they do both involve leap years). If someone asked you what the day before March 1 is, you’d probably ask them, “What year?” March 0 is, like January 0, simply a reference to the day before it, but it’s useful since March 0 can be either February 28 or 29, depending on the year.

While this is occasionally used in software (some old versions of Microsoft Excel will accept 3/0 as a date and simply plug in the correct day for the particular year, for example), it’s more commonly found in something known as the Doomsday rule.

It sounds fairly ominous, but the Doomsday rule is just a method for calculating what day of the year falls on for any given date. For example, by following the Doomsday rule, you could quickly tell that January 19, 1481 was a Wednesday. How? By figuring out what creator John Conway calls “the Doomsday.” This is the day of the week that certain calendar days will always fall on in a given year. April 4, June 6, and August 8 are just a few days of the year that will always fall on that year’s Doomsday. Another big one? March 0, i.e., the final day of February.

So, using 1481 as our example again, you can use a formula to determine that its Doomsday was Monday. (For the record, 2013’s Doomsday is Thursday.) From there, we could quickly ascertain that March 0 was a Monday, and for that particular year, February only had 28 days (since it was not a leap year), making “March 0” Monday, February 28, 1481. If you’re mathematically-minded, it’s a fun challenge. If you’re not, well, you can always look the day up on the internet or use a Doomsday calculator.

4. UNDECIMBER AND DUODECIMBER

There aren’t just odd and unusual days of the year. There are entire months as well. Remember the episode of The Simpsons where the school ordered faulty calendars with a 13th month (called Smarch)? Well, as it happens, we kind of had that once upon a time—namely, those left over from the days of the Roman calendar, which preceded the aforementioned Julian calendar. Much like how the process of moving from the Julian calendar to the Gregorian calendar left a few odd days out, the move from the Roman calendar to the Julian one actually added some.

These days, 67 in all, were then added into a pair of months between the November and December of 45 BC, and were referred to as intercalaris prior and intercalaris posterior, which are often called Undecimber (pronounced like “oon,” not “uhn”) and Duodecimber in modern days.

These names refer to the fact that December is named after the Latin word for ten (which itself came from the fact that the Roman calendar originally only had ten months and not twelve), while the Latin words for eleven and twelve (or in this case, thirteen and fourteen) are undecim and duodecim.

What’s more, the terms have even come to be used in modern computing. The Java programming language includes support for a 13-month calendar, and it refers to the 13th month as Undecimber.

5. MERCEDONIUS

Speaking of the Roman calendar, by the time Julius Caesar came along, it hadn’t had ten months for quite a while. Nearly 600 years, in fact. The Roman calendar that Caesar reformed was itself a reformed calendar constructed by King (not Emperor) Numa Pompilius sometime in the 7th century BC.

Prior to Pompilius’ changes, the Roman calendar, as we mentioned, had ten months: Martius, Aprilis, Maius, Iunius, Quintilis, Sextilis, September, October, November, and December. (Quintilis was later renamed Julius after Julius Caesar himself, while Sextilis was changed to Augustus in honor of his son/grand-nephew, Caesar Augustus.) King Numa Pompilius added Januarius and Februarius, giving us the twelve months we have today … except he also added another, forgotten month that hasn’t been in use for millennia: Mercedonius.

Mercedonius was a kind of a leap month, situated between Februarius and Martius, and was approximately 27 days. Although there was apparently some kind of formula to determine in which years Mercedonius was used and in which years it wasn’t, the implementation was spotty, since it was up to whoever the current Pontifex Maximus was at the time to decide if the month was used or not.

Since the month was used so sloppily, Julius Caesar simply eliminated it entirely when constructing the Julian calendar, rearranged the days throughout the year, and made a simple, easy-to-follow leap day system.

5 Clues Daenerys Targaryen Will Die in the Final Season of Game of Thrones

HBO
HBO

by Mason Segall

The final season of HBO's epic Game of Thrones is hovering on the horizon like a lazy sun and, at the end of the day, fans have only one real question about how it will end: Who will sit the Iron Throne? One of the major contenders is Daenerys of the thousand-and-one names, who not only has one of the most legitimate claims to the throne, but probably deserves it the most.

However, Game of Thrones has a habit of killing off main characters, particularly honorable ones, often in brutal and graphic ways. And unfortunately, there's already been some foreshadowing that writers will paint a target on Daenerys's back.

5. THE PROPHECIES

Carice van Houten in 'Game of Thrones'
Helen Sloan, HBO

What's a good fantasy story without a few prophecies hanging over people's heads? While the books the show is based on have a few more than usual, the main prophecy of Game of Thrones is Melisandre's rants about "the prince that was promised," basically her faith's version of a messiah.

Melisandre currently believes both Daenerys and Jon Snow somehow fulfill the prophecy, but her previous pick for the position died a grisly death, so maybe her endorsement isn't a good sign.

4. TYRION'S DEMANDS FOR A SUCCESSOR

Peter Dinklage and Emilia Clarke in a scene from 'Game of Thrones'
HBO

A particular scene in season seven saw Tyrion advising Daenerys to name a successor before she travels north to help Jon. She challenges him, "You want to know who sits on the Iron Throne after I'm dead. Is that it?" But that's exactly it. Tyrion is more than aware how mortal people are and wants to take precautions. He's seen enough monarchs die that he probably knows what warning signs to look for.

3. A FAMILY LEGACY

David Rintoul as the Mad King in 'Game of Thrones'
HBO

Daenerys is the daughter of the Mad King Aerys II, a paranoid pyromaniac of a monarch. More than once, Daenerys has been compared to her father, particularly in her more ruthless moments. Aerys was killed because of his insanity and arrogance. If Daenerys starts displaying more of his mental illness, she might follow in his footsteps to the grave.

2. HER DRAGONS AREN'T INVINCIBLE

Emilia Clarke in 'Game of Thrones'
HBO

The fall and subsequent resurrection of the dragon Viserion was one of the biggest surprises of season seven. Not only did it destroy one of Daenerys's trump cards, but it proved that her other two dragons were vulnerable as well. Since the three-headed dragon is the sigil of her house, this might be an omen that Daenerys is next on the chopping block.

1. THAT VISION

Emilia Clarke in 'Game of Thrones'
HBO

All the way back in season two, Daenerys received a vision in the House of the Undying of the great hall in King's Landing ransacked and covered in snow. Before she could even touch the iron throne, she was called away by her dragons and was confronted by her deceased husband and son. This is a clear indication that she might never sit the throne, something that would only happen if she were dead.

7 Tips for Winning an Arm Wrestling Match

iStock
iStock

Geoff Hale was playing Division II college baseball in Kansas City, Missouri, when he sat down and started flipping through the channels on his TV. There—probably on TBS—was Over the Top, the 1987 arm wrestling melodrama starring Sylvester Stallone as Lincoln Hawke, a truck driver who aspires to win his estranged son’s affections. And to do that, he has to win a national arm wrestling tournament. Obviously.

Neither the worst nor the best of Stallone’s efforts, Over the Top made Hale recall his high school years and how the fringe sport had satisfied his athletic interests, which weren't being met by baseball. “I had never lost a match,” Hale tells Mental Floss of his arm wrestling prowess. “The movie reminded me that I was good at it.”

That was 13 years ago. Now a professional competitor known as the Haleraiser, the full-time petroleum geologist has won several major titles. While you may not have the constitution for the surprisingly traumatic sport (more on that later), you might still want to handle yourself in the event of a spontaneous match breaking out. We asked Hale for some tips on what to do when you’re confronted with the opportunity to achieve a modest amount of glory while arm-grappling on a beer-stained table. This is what he told us.

1. KNOW THAT SIZE DOESN'T MATTER.

A child uses books to help in arm-wrestling an adult
iStock

Well, it does. But really only if your opponent knows what they’re doing. Otherwise, having a bowling pin for a forearm isn’t anything to be wary about. If anything, your densely-built foe may have a false sense of confidence. “Everyone has arm-wrestled since they were a kid and thinks they know what it is,” Hale says. “It looks easy, but there’s actually a very complex set of movements. It’s good to check your ego at the door.”

2. PRETEND YOU’RE PART OF THE TABLE.

A man offers to arm wrestle from behind a table
iStock

When you square up with your opposition to lock hands—thumb digging into the fleshy part, fingers wrapped around the back—don’t lean over the table with your butt in the air. And don’t make the common mistake of sitting down for a match, either. “It limits you from a technique standpoint,” Hale says, and could even open you up to injury.

Instead, you want to plant the foot that matches your dominant hand under the table with your hip touching the edge. With your free hand, grip the edge or push down on the top for stability. “Pretend like you’re part of the table,” Hale says. That way, you’ll be able to recruit your shoulders, triceps, and biceps into the competition.

3. REMEMBER TO BREATHE.

Two men engage in an arm wrestling match
iStock

If you’re turning the color of a lobster, you’re probably holding in your breath. “Don’t,” Hale says. Remember to continue taking in air through your nose. There’s no benefit to treating the match like a diving expedition. The lack of oxygen will just tire your muscles out faster.

4. BEAT THE HAND, NOT THE ARM.

Two hands appear in close-up during an arm wrestling contest
iStock

There are three basic techniques in arm wrestling, according to Hale: the shoulder press, the hook, and the top roll. The shoulder press recruits the shoulder right behind the arm, pushing the opposing appendage down as if you were performing a triceps pressdown. The hook is more complex, varying pressure from all sides and incorporating pulling motions to bend the wrist backward. For the best chance of winning, opt for the top roll, which involves sliding your hand up your opponent’s so your grip is attacking the top portion nearest the fingers. That way, he or she is recruiting fewer major muscle groups to resist. “When you beat the hand, the arm follows,” Hale says. Because this is more strategy than strength, you might wind up toppling some formidable-looking opponents.

5. IN A STALEMATE, WAIT FOR AN OPENING.

A man and woman engage in an arm wrestling contest
iStock

While lots of arm wrestling matches end quickly, others become a battle of attrition. When you find yourself locked up in the middle of the table, wait for your opponent to relax. They almost always will. “In a neutral position, it’s good to stay static, keeping your body and arm locked up,” Hale says. “You’re just waiting for your opponent to make a mistake.” The moment you feel their arm lose tension, attack.

6. TRY SCREAMING.

A woman screams while winning an arm wrestling contest
iStock

Arm wrestlers play all kinds of psychological games, and while some might be immune to trash talk, it’s likely your rival will be influenced by some selective insults. “You can make someone lose their focus easily,” Hale says. “In a stalemate, you can give them a hard time, tell them they’re not strong. It’s intimidating to be out of breath and to see someone just talking.”

7. WHEN ALL ELSE FAILS, GO SECOND.

A man struggles while losing an arm wrestling contest
iStock

Arm wrestling exacts a heavy toll on winners and losers alike: The prolonged muscle contractions can easily fatigue people not used to the exertion. If you fear a loss from a bigger, stronger opponent, conspire to have them wrestle someone else first, then take advantage of their fatigue.

If all goes well, you might want to consider pursuing the sport on more competitive levels—but you probably shouldn’t. “It takes a toll on the body,” Hale says. “I’ve got tendonitis and don’t compete as much as I used to. On the amateur level, it’s common to see arm breaks, usually the humerus [upper arm] bone. The body was not really made for arm wrestling.”

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