ThinkStock/Erin McCarthy
ThinkStock/Erin McCarthy

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.

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Kevork Djansezian/Getty Images for PCA
12 Surprising Facts About Robin Williams
Kevork Djansezian/Getty Images for PCA
Kevork Djansezian/Getty Images for PCA

Robin Williams had a larger-than-life personality. On screen and on stage, he embodied what he referred to as “hyper-comedy.” Offscreen, he was involved in humanitarian causes and raised three children—Zak, Zelda, and Cody. On July 16, HBO debuts the documentary Robin Williams: Come Inside My Mind, directed by Marina Zenovich. The film chronicles his rise on the L.A. and San Francisco stand-up comedy scenes during the 1970s, to his more dramatic roles in the 1980s and '90s in award-winning films like Dead Poets Society; Good Morning, Vietnam; Awakenings; The Fisher King; and Good Will Hunting. The film also focuses on August 11, 2014, the date of his untimely death. Here are 12 surprising facts about the beloved entertainer.

1. ROBIN WILLIAMS GOT HIS START AT A COMEDY WORKSHOP INSIDE A CHURCH.

A still from 'Robin Williams: Come Inside My Mind' (2018)
HBO

After leaving Juilliard, Robin Williams found himself back in his hometown of San Francisco, but he couldn’t find work as an actor. Then he saw something for a comedy workshop in a church and decided to give it a shot. “So I went to this workshop in the basement of a Lutheran church, and it was stand-up comedy, so you don’t get to improvise with others, but I started off doing, ostensibly, it was just like improvising but solo," he told NPR. "And then I started to realize, ‘Oh.’ [I started] building an act from there."

2. HE FORMED A FRIENDSHIP WITH KOKO THE GORILLA.

In 2001, Williams visited Koko the gorilla, who passed away in June, at The Gorilla Foundation in Northern California. Her caregivers had shown her one of his movies, and she seemed to recognize him. Koko repeatedly signed for Williams to tickle her. “We shared something extraordinary: laughter,” Williams said of the encounter. On the day Williams died, The Foundation shared the news with Koko and reported that she fell into sadness.

3. FOR A TIME, HE WAS A MIME IN CENTRAL PARK.

In 1974, photographer Daniel Sorine captured photos of two mimes in New York's Central Park. As it turned out, one of the mimes was Williams, who was attending Juilliard at the time. “What attracted me to Robin Williams and his fellow mime, Todd Oppenheimer, was an unusual amount of intensity, personality, and physical fluidity,” Sorine said. In 1991, Williams revisited the craft by playing Mime Jerry in Bobcat Goldthwait’s film Shakes the Clown. In the movie, Williams hilariously leads a how-to class in mime.

4. HE TRIED TO GET LYDIA FROM MRS. DOUBTFIRE BACK IN SCHOOL.

As a teen, Lisa Jakub played Robin Williams’s daughter Lydia Hillard in Mrs. Doubtfire. “When I was 14 years old, I went on location to film Mrs. Doubtfire for five months, and my high school was not happy,” Jakub wrote on her blog. “My job meant an increased workload for teachers, and they were not equipped to handle a ‘non-traditional’ student. So, during filming, they kicked me out.”

Sensing Jakub’s distress over the situation, Williams typed a letter and sent it to her school. “A student of her caliber and talent should be encouraged to go out in the world and learn through her work,” he wrote. “She should also be encouraged to return to the classroom when she’s done to share those experiences and motivate her classmates to soar to their own higher achievements … she is an asset to any classroom.”

Apparently, the school framed the letter but didn’t allow Jakub to return. “But here’s what matters from that story—Robin stood up for me,” Jakub wrote. “I was only 14, but I had already seen that I was in an industry that was full of back-stabbing. And it was entirely clear that Robin had my back.”

5. HE WASN’T PRODUCERS' FIRST CHOICE TO PLAY MORK ON MORK & MINDY.

Anson Williams, Marion Ross, and Don Most told The Hallmark Channel that a different actor was originally hired to play Mork for the February 1978 Happy Days episode “My Favorite Orkan,” which introduced the alien character to the world. “Mork & Mindy was like the worst script in the history of Happy Days. It was unreadable, it was so bad,” Anson Williams said. “So they hire some guy for Mork—bad actor, bad part.” The actor quit, and producer Garry Marshall came to the set and asked: “Does anyone know a funny Martian?” They hired Williams to play Mork, and from September 1978 to May 1982, Williams co-headlined the spinoff Mork & Mindy for four seasons.

6. HE “RISKED” A ROLE IN AN OFF-BROADWAY PLAY.

Actor Robin Williams poses for a portrait during the 35th Annual People's Choice Awards held at the Shrine Auditorium on January 7, 2009 in Los Angeles, California
Michael Caulfield, Getty Images for PCA

In 1988, Williams made his professional stage debut as Estragon in the Mike Nichols-directed Waiting for Godot, which also starred Steve Martin and F. Murray Abraham. The play was held off-Broadway at Mitzi E. Newhouse Theater at Lincoln Center. The New York Times asked Williams if he felt the show was a career risk, and he responded with: “Risk! Of never working on the stage again! Oh, no! You’re ruined! It’s like you're ruined socially in Tustin,” a town in Orange County, California. “If there’s risk, you can’t think about it,” he said, “or you’ll never be able to do the play.”

Williams had to restrain himself and not improvise during his performance. “You can do physical things,” he said, “but you don’t ad lib [Samuel] Beckett, just like you don’t riff Beethoven.” In 1996, Nichols and Williams once again worked together, this time in the movie The Birdcage.

7. HE USHERED IN THE ERA OF CELEBRITY VOICE ACTING.

The 1992 success of Aladdin, in which Williams voiced Genie, led to more celebrities voicing animated characters. According to a 2011 article in The Atlantic, “Less than 20 years ago, voice acting was almost exclusively the realm of voice actors—people specifically trained to provide voices for animated characters. As it turns out, the rise of the celebrity voice actor can be traced to a single film: Disney’s 1992 breakout animated hit Aladdin.” Since then, big names have attached themselves to animated films, from The Lion King to Toy Story to Shrek. Williams continued to do voice acting in animated films, including Aladdin and the King of Thieves, Happy Feet, and Happy Feet 2.

8. HE FORGOT TO THANK HIS MOTHER DURING HIS 1998 OSCAR SPEECH.

In March 1998, Williams won a Best Supporting Actor Oscar for his performance as Sean Maguire in Good Will Hunting. In 2011, Williams appeared on The Graham Norton Show, and Norton asked him what it was like to win the award. “For a week it was like, ‘Hey congratulations! Good Will Hunting, way to go,'” Williams said. “Two weeks later: ‘Hey, Mork.’”

Then Williams mentioned how his speech accidentally left out one of the most important people in his life. “I forgot to thank my mother and she was in the audience,” he said. “Even the therapist went, ‘Get out!’ That was rough for the next few years. [Mom voice] ‘You came through here [points to his pants]! How’s the award?’”

9. HE COMFORTED STEVEN SPIELBERG DURING THE FILMING OF SCHINDLER’S LIST.

At this year’s 25th anniversary screening of Schindler’s List, held at the Tribeca Film Festival, director Steven Spielberg shared that Williams—who played Peter Pan in Spielberg’s Hook—would call him and make him laugh. “Robin knew what I was going through, and once a week, Robin would call me on schedule and he would do 15 minutes of stand-up on the phone,” Spielberg said. “I would laugh hysterically, because I had to release so much.”

10. HE HELPED ETHAN HAWKE GET HIS AGENT.

During a June 2018 appearance on The Graham Norton Show, Ethan Hawke recalled how, while working on Dead Poets Society, Williams was hard on him. “I really wanted to be a serious actor,” Hawke said. “I really wanted to be in character, and I really didn’t want to laugh. The more I didn’t laugh, the more insane [Williams] got. He would make fun of me. ‘Oh this one doesn't want to laugh.’ And the more smoke would come out of my ears. He didn’t understand I was trying to do a good job.” Hawke had assumed Williams hated him during filming.

After filming ended, Hawke went back to school, but he received a surprising phone call. It was from Williams’s agent, who—at Williams's suggestion—wanted to sign Hawke. Hawke said he still has the same agent today.

11. HE WAS ALMOST CAST IN MIDNIGHT RUN.

In February 1988, Williams told Rolling Stone how he sometimes still had to audition for roles. “I read for a movie with [Robert] De Niro, [Midnight Run], to be directed by Marty Brest,” Williams said. “I met with them three or four times, and it got real close, it was almost there, and then they went with somebody else. The character was supposed to be an accountant for the Mafia. Charles Grodin got the part. I was craving it. I thought, ‘I can be as funny,’ but they wanted someone obviously more in type. And in the end, he was better for it. But it was rough for me. I had to remind myself, ‘Okay, come on, you’ve got other things.’”

In July 1988, Universal released Midnight Run. Just two years later, Williams finally worked with De Niro, on Awakenings.

12. BILLY CRYSTAL AND WILLIAMS USED TO TALK ON THE PHONE FOR HOURS.

Actors Robin Williams (L) and Billy Crystal pose at the afterparty for the premiere of Columbia Picture's 'RV' on April 23, 2006 in Los Angeles, California
Kevin Winter, Getty Images

Starting in 1986, Williams, Billy Crystal, and Whoopi Goldberg co-hosted HBO’s Comic Relief to raise money for the homeless. Soon after Williams’s death, Crystal went on The View and spoke with Goldberg about his friendship with Williams. “We were like two jazz musicians,” Crystal said. “Late at night I get these calls and we’d go for hours. And we never spoke as ourselves. When it was announced I was coming to Broadway, I had 50 phone messages, in one day, from somebody named Gary, who wanted to be my backstage dresser.”

“Gary” turned out to be Williams.

Robin Williams: Come Inside My Mind premieres on Monday, July 16 at 8 p.m. ET on HBO.

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Walt Disney Pictures
10 Facts About Hocus Pocus
Walt Disney Pictures
Walt Disney Pictures

In a 2014 Reddit AMA, Bette Midler said she'd be interested in doing a Hocus Pocus sequel. "You have to go to send in your cards to the Walt Disney company," she said. "The ball's in their court." While you get those cards ready, here are some facts about the original, which arrived in theaters 25 years ago today.

1. THE STORY ORIGINATED AS A BEDTIME STORY.

The story for Hocus Pocus came about after writer David Kirschner invented a bedtime story for his kids. He later wrote the story up and submitted it to Muppet Magazine (why does this not still exist?), where it gained recognition.

2. THE WRITERS USED PROPS TO PITCH IT TO STUDIO EXECUTIVES.

Bette Midler in 'Hocus Pocus' (1993)
Walt Disney Pictures

To pitch the story to Disney, the writers had execs enter a dark room with broomsticks and a vacuum cleaner hanging from the ceiling. They also scattered 15 pounds of candy corn throughout the room in an effort to invoke Halloween nostalgia. It obviously worked!

3. IT WAS NOT AN IMMEDIATE HIT.

Though it’s a cult classic now, Hocus Pocus didn’t do that well when it first came out in 1993, perhaps because it was released in July instead of September or October. Though it didn’t have a terrible opening—$8,125,471, putting it in fourth place at the box office that weekend—it fell to $2,017,688 a few weeks later, and bad reviews from the critics didn’t help matters.

Entertainment Weekly was particularly put off by the movie, calling it a “piece of corny slapstick trash” and saying that “It’s acceptable scary-silly kid fodder that adults will find only mildly insulting. Unless they’re Bette Midler fans. In which case it’s depressing as hell.”

4. BETTE MIDLER LOVES IT.

Bette Midler, by the way, has said that Hocus Pocus is her favorite film out of all of the films she’s ever done. (At least as of 2008.) Thora Birch agreed, recently saying, “The most fun I ever had on a film was Hocus Pocus.”

5. KATHY NAJIMY LOVES IT, TOO.

Midler isn't the only star of the film who isn't immune to its allure: Kathy Najimy has said she watches the movie with her family every year on August 15.

6. IT COULD HAVE STARRED LEONARDO DICAPRIO.

The role of Max was originally offered to Leonardo DiCaprio. He turned it down to do What’s Eating Gilbert Grape.

7. SARAH JESSICA PARKER IS RELATED TO A WOMAN FAMOUSLY ACCUSED OF BEING A WITCH.

Had Sarah Jessica Parker known then what she knows now, she might have approached the role of Sarah Sanderson a little differently. When the actress went on the show Who Do You Think You Are to trace her family history, Parker discovered that one of her ancestors was Esther Elwell, one of the women accused of being a witch during the Salem Witch Trials. After a young girl said she saw Esther’s “spectre” strangling neighbor Mary Fitch, Elwell was arrested, but escaped going to trial.

8. THORA BIRCH REVISITED THE NEIGHBORHOOD IN AMERICAN BEAUTY.

While the kids are prematurely celebrating victory against the Sanderson sisters after locking them in the kiln, they’re shown talking in front of a house as they walk to a park. The house was later used as the house Thora Birch’s character lived in for American Beauty.

9. THE KIDS WEREN'T HUGE FANS OF THE CATS.

The kids all hated working with the cats. Many different cats were used to represent Binx, and each one served a different purpose—one was good at cuddling with the kids, one would jump on command, etc. Every time a new cat was used, the children would have to coerce the kitty to trust them by using treats and a clicker. They got sick of it.

10. MUCH OF THE ORIGINAL CAST REUNITED FOR A 20TH REUNION.

Most of the cast participated in a 20th anniversary event for D23 (the Disney fan club) members. Sarah Jessica Parker and Bette Midler were not in attendance, but pretty much everyone else was, including Kathy Najimy (Mary Sanderson), Vinessa Shaw (Allison), Omri Katz (Max), Thora Birch (Dani), and Doug Jones (Billy Butcherson). You can watch some of that reunion above.

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