Why are there 12 Months in a Year?

Summary

Podcast Summary: "Who Smarted?"

Episode: Why are there 12 Months in a Year?

Date: December 26, 2025
Podcast: Who Smarted? (Atomic Entertainment / Starglow Media)
Host: (Unnamed, with characters "Cal" the Calendar and Co-host)

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Episode Overview

This fun, fact-filled episode explores why we have 12 months in a year, why months and weeks are structured the way they are, and the historical quirks and mistakes of our modern calendar. With humor, interactive trivia, and clever characters (like Cal, the personified calendar), the show guides young listeners through the confusing and often illogical evolution of time-keeping—from ancient civilizations through the Romans, all the way to Pope Gregory XIII's calendar reform. Along the way, listeners discover surprising facts, odd calendar errors, and the fascinating blend of science and history behind everyday dates.

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Key Discussion Points & Insights

1. Why Do We Have Months and Years?

• [00:01] Host introduces the idea that living without months or years is hard to imagine today, but ancient humans managed before calendars.
• Days were easy to define (sunrise to sunset), but grouping days into weeks and months took ingenuity.

2. Calendars Are Kinda Messy!

• [01:43] Host observes how the current calendar seems messy:
  • Weeks are always 7 days, but months have varying numbers of days (28–31).
  • February, especially, is odd—with 28 days, plus one extra day every four years.
• There have been modern proposals to "fix" the calendar, but inertia (and calendars like Cal!) keep things as they are.

3. Meet "Cal" the Calendar (and his Big Ego)

• [02:58] Character "Cal" appears as a comical calendar with a wizard complex, claiming to be “the great and powerful calendar,” brimming with both lore and flaws.
  • Memorable quote [03:12], Calendar:

    "I am the great and powerful calendar. I contain the names of gods, goddesses, and emperors."

• [04:03] Cal is unmasked as a little desk calendar from 2012, highlighting how “outdated” even our calendar knowledge can be.

4. How Did Weeks Get Seven Days?

• [05:14] Cal explains that ancient societies had all sorts of weeks:

  • Egyptians: 10-day weeks
  • Central Asia/Middle East: five-day weeks
  • West Africa: four-day weeks

• The seven-day week comes from the Babylonians (adopted by Romans), somewhat based on the moon’s phases.

  • Interactive segment [05:42]:
    Kids invited to guess why seven days? (Answer: Moon phases.)

• Cal clarifies [06:03]:

  "Ah, it may be right, but it’s not correct... The lunar cycle is actually 29 and a half days. So the week is off by a little bit."

5. Where Do “Months” Come From?

• The word "month" is derived from "moon."
  • Cal [06:56]:

  "Yes, the word month actually comes from a word meaning moon. Moo."

• The Romans gave most of our months their names:
  • March, May, June: named for mythological figures.
  • April: related to spring.
  • September–December: literally mean 7th-10th months (showing calendar drift!).

6. The Roman Calendar’s Mistakes

• The original Roman calendar had just 10 months and ignored winter.
  • January and February were added later (from Janos and Februs); initially at the end of the year.
• Why is February so short?
  • Romans thought even numbers were unlucky, so months were mostly 29 or 31 days. The unlucky even days were all dumped in February, which ended up at 28 days.
    • Cal [08:15]:

    "Instead of creating a whole year of bad luck, the Romans decided to put all the bad vibes on only one month. February."

7. Julius Caesar and the Leap Year

• Julius Caesar adopted a 365-day calendar, based on Egyptian models; leap years added to correct drift.
  • February got an extra day every four years.
  • Months Quintilis and Sextilis became “July” and “August,” renamed for Julius Caesar and Augustus Caesar.
    • Host [10:34]:

      "Ooh, smartypants. Do the names Julius and Augustus sound familiar? What months do you think are named after them? Did you say July and August?"

8. Naming the Days of the Week

• [11:01] Romans named...
  • Sunday after the Sun, Monday after the Moon.
  • Other days after Roman gods/planets, e.g., Mars = Tuesday.
• [12:19] English names sometimes swapped in Norse/Germanic gods (e.g., Thor’s Day = Thursday).
  • Host [12:19]:

    "Thursday, also known as Thor's day, After the hammer-wielding Norse God of thunder who inspired Marvel superhero."

9. A Year That’s Just a Guess

• Our calendar’s “year zero” is based on a guess at the birth of Jesus—now known to be a bit off.
  • Cal [12:38]:

    "Well, it's not really counting from anything... every year is just a random number."

10. From the Julian to the Gregorian Calendar

• The Julian calendar made too many leap years, causing drift (spring started at the wrong time).
• Pope Gregory XIII fixed this with the Gregorian calendar (1582), cutting leap years and eliminating 10 days to realign spring.
  • [13:52–14:59] Countries didn’t all adopt it at once, resulting in “time travel confusion.”

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Notable Quotes & Memorable Moments

• Calendar’s funny reveal:

  "Hey, you're not an all-powerful wizard. You're just a little desk calendar from 2012." [04:03]

• On February’s “bad luck”:

  "Instead of creating a whole year of bad luck, the Romans decided to put all the bad vibes on only one month. February." – Cal [08:15]

• Leap year history and chaos:

  "In October of 1582, people went to bed on October 4th and woke up the next morning on October 15th." [13:51]

• On the calendar’s resilience:

  "If you ever make a mistake, don’t feel bad—think of the calendar. It's made lots of mistakes and it's still going strong." – Host [14:59]

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Timestamps for Important Segments

• 00:01–01:25 – Birthdays, time-keeping before calendars, and the show’s main questions.
• 01:43–02:58 – Why our calendar seems inconsistent.
• 02:58–04:20 – Introduction of Cal, the calendar with an attitude.
• 05:14–06:03 – Origins of the seven-day week.
• 06:56–07:40 – Roman naming of months; meaning behind “month.”
• 08:15–09:04 – February’s oddness and early calendar superstitions.
• 09:04–10:55 – Julius Caesar, leap years, and month names.
• 11:01–12:19 – Weekday names, Roman and Norse influences.
• 12:38–13:25 – The fuzzy logic behind year zero and calendar years.
• 13:52–14:59 – The Gregorian reform and global calendar confusion.
• 14:59–15:18 – Final “mistakes” lesson and calendar resilience.

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Episode Takeaway

The calendar we use is a patchwork of astronomy, mythology, superstition, historical guesswork, and several “fixes” that, despite its messiness, keeps the modern world running. Even though it has a lot of quirks and hilarious errors, it’s a reminder that inventions—even the really important ones—are often imperfect, but can still stand the test of time.

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Fun Fact For After-Listening:

"If you ever make a mistake, don’t feel bad—think of the calendar. It's made lots of mistakes and it's still going strong." – Host [14:59]

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This episode is a perfect example of Who Smarted?’s engaging blend of education and humor, making even topics as dry as the calendar come alive with fun, memorable facts and interactive storytelling.

Transcript

[Host]

Psst. Smarty pants. When's your birthday? Go ahead, shout out the date. I'm guessing you all got it right. But that's an easy question. The hard question is this. Tell me your birthday without naming the month. Huh? For example, how many days is your birthday from the start of the year? 75? 246? 338. Not so simple now, is it? Unless you were born in January. Try this. You know how many years old you are? But how many days have gone by since you were born? Yeah, it's hard to imagine living without months or years. But ancient humans did just that until they figured out the best way to group days together. Of course, first they had to figure out days, which wasn't too complicated. Sun goes up, sun goes down. That's a day. But what about the rest? Why do we have seven day weeks and months that vary from 28 days to 31 days? Where do the names of the months come from? And best of all, did you know the calendar you used today is full of mistakes? It's time for another whiff of science and history on who smarted.

[Co-host]

Who's smarted? Who's smart? Is it you? Is it me? Is it science or history? Listen up, everyone. We make smarting lots of fun. But who's smarted?

[Host]

Quick question, smartypants. How often do you use a calendar? You probably don't give it much thought, but chances are you use it a lot. At the very least, you refer to the months of the year to know when school starts and ends, which holidays are coming. Merry Christmas, when summer is. Yay. The start of sports seasons, your birthday. Do you have lessons or practices on certain days of the week? It isn't easy keeping track of all those things without a calendar at the same time. Looking at today's calendar subjectively, which means based on opinion, it might seem like a bit of a mess. Huh? Well, for starters, every week has seven days. But every month is different. Some have 30 days, some 31. And what is up with February? It only has 28 days, but every four years, it magically gains a day. Recently, there have been some proposals to do away with the current calendar and create a simpler one. One proposal would give February 30 days and silence.

[Calendar]

Who dares mess with the sacred keeper of days, months and years?

[Host]

Sorry, I didn't mean to. Uh, excuse me. Who are you?

[Calendar]

I am the great and powerful calendar. I contain the names of gods, goddesses, and emperors.

[Host]

Yes, that's true, of course. One third of the months are simply named after numbers.

[Calendar]

Silence. I demand Respect. I wouldn't be the most widely used calendar in the world if I were not flawless.

[Host]

What is it, Smarto? What do you see? A curtain. Go check it out, boy.

[Calendar]

Pay no attention to the man behind the curtain.

[Host]

It's.

[Cal]

It's. Oh, dear. You got me.

[Host]

Hey, you're not an all powerful wizard. You just a little desk calendar from 2012.

[Cal]

Hey, calendars come in all shapes and sizes. I may be a little out of date, but I'm still a calendar. Call me Cal.

[Host]

Hi, Cal. So what's with that all powerful wizard thing?

[Cal]

I thought I'd get more respect that way. I don't want you or anyone else replacing me.

[Host]

I get it. Listen, replacing the calendar system would take a ton of work. Especially when so much of the modern world relies on it. Trust me, you're not going anywhere soon. People may have better ideas, but by and large, the calendar works.

[Cal]

Really? But nothing lines up properly. Here, I'll show you how many days are in a week.

[Host]

Uh, smarty pants? Go ahead. Shout out the number of days in a week. Yep, I think we can all agree there are seven days in a week.

[Cal]

Now there are. But that wasn't always the case.

[Host]

Huh?

[Cal]

Thousands of years ago, many different people had many different calendars with many different weeks. Ancient Egyptians had 10 day weeks. People in Central Asia and the Middle east created five day weeks. And several tribes in West Africa followed four day weeks. The seven day week comes to us from the ancient Romans in Europe, who got it from the Babylonians who also lived in the Middle East.

[Host]

Smartypants, can you guess why the Babylonians and Romans used a seven day week? Is it because A, moon phases are seven days apart? B, some foods spoil after seven days? Or C, because there are seven continents? If you said A, you're right.

[Cal]

Ah, it may be right, but it's not correct. There are four major phases of the moon. A half moon, full moon, another half moon, and a new moon, which you can't see. If each phase were seven days apart, you'd go through a full cycle in 28 days. Seven times four. But the lunar cycle is actually 29 and a half days. So the week is off by a little bit.

[Host]

Whoa.

[Cal]

The Babylonians recognized this problem early on. So after four weeks, they'd add a day or two, creating groups of 29 or 30 days. Do you know what these groups became known as?

[Host]

Any guesses, smarty pants? You got it. Moon pies.

[Cal]

Moon pies.

[Host]

JK we call them months.

[Cal]

Yes, the word month actually comes from a word meaning moon. Moo. The Romans named the months we use today. They started off strong, naming March, May, and June after mythological gods and goddesses. April's name connects to spring. After that, they got lazy and just numbered the rest of the months. For example, September means seventh month, October means eighth month, November means ninth month, and December means tenth month.

[Host]

But isn't December the twelfth month?

[Cal]

That's what I'm saying. The calendar is all wrong. The Roman Calendar originally had 10 months. Since they didn't bother counting the winter months, eventually they decided to do that. So they added January and February, named after the Roman gods Janos and Februs. They put those at the end of the calendar as the 11th and 12th months.

[Host]

That makes sense.

[Cal]

Until they moved them, but I'm getting to that. The Romans thought, but even numbers were bad luck, so their months were either 29 or 31 days. But if you add together the days of 12 odd numbered months, you get a year with an even number of days. Instead of creating a whole year of bad luck, the Romans decided to put all the bad vibes on only one month. February. That's why it has an even number of days. 28. That made a calendar year with a nice odd number of days. 355.

[Host]

Uh, but an Earth year is 365 days.

[Cal]

Yep. Another problem. Soon the Roman calendar was out of step with the seasons, with spring starting as late as May. Then along came Emperor Julius Caesar, and he made some changes. He adopted a 365 day calendar based on the seasons. Following what was already being done in Egypt and Greece. He added days to every month except February. That month he saved for his other new creation, the leap year, which gives February an extra day every four years. Since a year is technically a little more than 365 days.

[Host]

Huh?

[Cal]

This new calendar, called the Julian calendar, put January and February at the beginning of the year. So September, October, November, and December became the 9th, 10th, 11th, and 12th months, even though those numbers don't match their names. However, they did change two months, Quintilis and Sextillus, which mean fifth and sixth months. Those months were renamed after Julius Caesar and another powerful emperor, Caesar Augustus.

[Host]

Ooh, smartypants. Do the names Julius and Augustus sound familiar? What months do you think are named after them? Did you say July and August?

[Cal]

They put those months between June and.

[Host]

September with July and August. This Julian calendar seems a lot like the one we use today.

[Cal]

Yes, but there were still more problems.

[Host]

And you'll hear all about them right after this quick break. Now back to who smarted? Okay. Smarty pants. You heard how the months got their names, but who named the days of the week? If you guessed the Romans. You're right. The Romans named Sunday after the sun and Monday after the moon. The remaining days were named after planets which also got their names from Roman mythology. Tuesday is named after the Roman God Mars, Wednesday is Mercury, Thursday is Jupiter, Friday is Venus, and Saturday is named after Saturn. When the English translated the days, they changed them slightly to reflect mythological German and Norse gods who were similar to Roman ones. In fact, one weekday is named after a Norse God who inspired a popular comic book character. Any guesses? Which day is it? Wednesday, Thursday or Friday? The answer is Thursday, also known as Thor's day, After the hammer wielding Norse God of thunder who inspired Marvel superhero.

[Calendar]

Thor, who is great and powerful like me.

[Host]

Yes, Cal, you're powerful. You don't need to use the wizard machine.

[Cal]

Even with all my mistakes?

[Host]

Even with all your mistakes.

[Cal]

Including the year.

[Host]

Uh, what's up with the year?

[Cal]

Well, it's not really counting from anything. When the Romans joined the Christian faith and became followers of Jesus, they decided to count years from the moment of Jesus birth. Since Jesus was born hundreds of years earlier, the best they could do was guess the date. And now it looks like they were wrong. Even Christian leaders today say Jesus was likely born several years before year one. That means every year is just a random number.

[Host]

So why do we use the Julian calendar with its mistakes when so many other calendars exist? There's a Hebrew calendar, a Buddhist calendar, a Muslim calendar, a Chinese calendar, even an ancient Mayan calendar. Why use the Julian one?

[Cal]

We don't. The Julian calendar had another big mistake that had to be corrected. Too many leap years.

[Host]

Too many leap years?

[Cal]

Yes. All the extra days cause spring to start at the wrong time. 400 or so years ago, Pope Gregory XIII came up with a new calendar, the Gregorian calendar. It cut down the number of leap years using fancy math I won't get into right now. And to get spring back on track, it eliminated 10 days. In October of 1582, people went to bed on October 4th and woke up the next morning on October 15th. Of course, not every country followed this new calendar. So some places were ahead of others by 10 days, creating a lot of confusion. Then in 1752, the British Empire, which controlled a large part of the world, finally adopted the Gregorian calendar. And now it's the most used calendar in the world, despite its mistakes.

[Host]

This is a good lesson for all you smarty pants. If you ever make a mistake, don't feel bad think of the calendar. It's made lots of mistakes and it's still going strong.

[Calendar]

The calendar is always right.

[Host]

Except when it's wrong, which is almost every day. A timeless shout out to Eliza in Woking, Surrey, uk. I hear you love sharing all the amazing things you've learned with friends and family and seem to have an interesting fact for every topic that comes up that is the smarty pants spirit Eliza. Well done this episode. The Calendar was written by Dave Beaudry and voiced by Taya Garlid and Jerry Colbert. Technical direction and sound design by Josh Hahn. Whosmarted is recorded and mixed at the Relic Room Studios. Our Associate Producer is Max Kamasky. The theme song is by Brian Suarez with lyrics written and performed by Adam Tex Davis. Whosmarted was created and produced by Adam Tex Davis and Jerry Colbert. This is an Atomic Entertainment production.