Look at your phone right now. What's today's date?
Now ask yourself a weird question. Why is the month called what it is? Why are some months 30 days and some are 31 and February is just sad? Why does the week have seven days? Why is the year 365 days, except every four years it's 366, except every 100 years it's not, except every 400 years it is again?
The answer is going to bother you.
We use this calendar because a Roman dictator wrote one version of it, then a Pope fixed it 1,500 years later, and we never got around to building anything better. That's it. That's the whole reason.
Now imagine this. We're sending people to Mars. We get to start a new world. New buildings. New laws. New everything. Do we drag our broken calendar with us? Or do we finally fix the thing?
Let me show you what a clean calendar would look like. And why we won't build it on Mars unless we choose to, hard, on day one.
What's wrong with the calendar you use
Just so we're on the same page, here's what's broken about the calendar in your phone.
The months are random. Thirty, thirty-one, twenty-eight, thirty-one. No pattern. Just old Roman politics. A guy named Julius wanted his month long. A guy named Augustus wanted his at least as long. February got robbed.
The week doesn't fit the year. Fifty-two weeks times seven days is 364. We have a leftover day every year. Two in leap years. Where do you put them? Whoever made the calendar just kind of shrugged.
The same date is a different weekday every year. Your birthday is on Tuesday this year, Thursday next year. Every business in the world has to keep redoing schedules. Every store sells a new calendar every December.
The leap year rule is a Rube Goldberg machine. Every four years, add a day. Except every 100 years, don't. Except every 400 years, do. Try explaining that to a sixth grader.
It still drifts. Even with all the leap year math, the year is about 26 seconds too long. In a few thousand years, we'll be off by a whole day. Then somebody will have to fix it again.
There's no Year 0. We jump from 1 BC straight to 1 AD. Try doing math across that boundary. It breaks.
This is the system we run the planet on. We run banks, hospitals, rockets, weddings, and elections on it. It's a mess held together by habit.
People have tried to fix it. They lost.
Smart people have noticed all this. They tried to fix it. They got beat by something stronger than math.
In 1902, an English guy named Moses Cotsworth made a clean version. Thirteen months of 28 days each. Every month starts on Sunday. Every date falls on the same weekday every year, forever. Beautiful.
Kodak actually used it inside the company until 1989. The League of Nations almost made it the world standard.
It died because of religion. The seven-day week, with one rest day, runs through Jewish, Christian, and Muslim life. Cotsworth's plan needed one "extra day" that wasn't inside any week. That broke the chain. The religious folks said no. Also, Friday the 13th would happen every month, which freaked people out.
In the 1930s a rich American woman named Elisabeth Achelis tried a different fix. Four equal quarters. It made it all the way to a United Nations vote in 1955. The United States killed it. Same reason. Off-week extra days broke the Sabbath.
In 2012 a physicist named Richard Henry tried again. He fixed the religious problem. No extra days outside the week. Instead, every five or six years, the calendar adds a whole extra week. Weeks stay clean. Sabbath stays clean. Every date falls on the same weekday forever. Johns Hopkins quietly uses it for their school schedule.
It still hasn't gone global. Why? Because changing the calendar means changing every law, every contract, every birthday, every database in the world. The pain is up front. The benefit is spread out. So we don't do it, even when we know we should.
The Gregorian calendar isn't winning because it's good. It's winning because it's already here. Same reason we still type on a QWERTY keyboard. Same reason America still measures things in feet. Once a bad standard gets locked in, getting out of it costs more than living with it.
Mars is our one shot
Now picture a Mars colony. A few thousand people. A new world. No 8 billion people with old habits. Just a small group with a chance to write the rules from scratch.
This is the one chance in human history to start clean. We will probably blow it. But let's at least walk through what clean would look like.
First, the facts of Mars.
A Mars day, called a sol, is 24 hours and about 40 minutes. Close to an Earth day but a little longer.
A Mars year is 668.59 sols. Almost twice as long as an Earth year. But that .59 is the same kind of headache we have on Earth. It doesn't divide cleanly.
So we have two choices.
Choice A. Build a Mars calendar that tracks Mars seasons. Smart people have already done this. A guy named Thomas Gangale designed one in 1985 called the Darian Calendar. Twenty-four months. Twenty-eight sols each. A small fix at the end of each year to handle the .59. It works.
Choice B. Forget Mars seasons entirely. Build a calendar that ignores the planet's trip around the sun. Make it pure math.
Choice B is the wild one. Stay with me.
The clean base-10 calendar
Try this on for size. A Mars calendar that uses only ten.
- One sol equals one day.
- One week equals ten sols.
- One month equals five weeks, so fifty sols.
- One year equals ten months, so 500 sols.
That's it. Forever. No leap year. No fixing. No drift in the math. Every month has the same number of days. Every week has the same number of days. Every birthday falls on the same weekday for life.
Now you might say, "wait, Mars actually takes 668.59 sols to go around the sun. Your 500-sol year is going to drift against the seasons."
Yes. Big time. The "Mars year" in this calendar will pass through every Martian season over about 25 years.
You might say, "isn't that a disaster?"
Here's the trick. Mars colonists don't live off Mars seasons. They live in sealed buildings with fake lights. They grow food in trays under bulbs. Their day is set by their work schedule, not by what season it is outside.
Earth calendars track Earth seasons because for thousands of years our lives depended on knowing when to plant, when to harvest, when the river floods. A Mars colony doesn't have that. The "outside" doesn't grow food. The "outside" is poison. Inside, you grow lettuce under a lamp every day, all year.
So Mars might be the first place humans ever lived where the calendar doesn't have to match the planet. It just has to organize the people.
"But what about sunrise?"
Good question. The clock side is rock solid.
The sun on Mars rises at "6:00" in the morning every sol. Sets at "18:00" every evening. That part doesn't change. The day stays the day, forever.
What drifts is the feel of the seasons. In Year 1, "Month 1" might land during Mars spring. In Year 6, that same "Month 1" lands in Mars summer. In Year 12, winter. In Year 25, back to spring.
This is less weird than it sounds. People in Alaska already live like this. "Morning" in June means the sun has been up for hours. "Morning" in December means the sun won't come up till lunch. They get used to it.
There's actually something cool about it. A kid born on the colony's Founding Day would have their birthday in spring as a child. Summer as a teenager. Fall as a young adult. Winter when they're older. Spring again at the end. Their whole life would walk through every Mars season once.
You can keep a second calendar around if you want to know what the seasons are doing outside. It just won't be the calendar you live in.
Don't drag Earth with you
Here's the part where I get pushy.
We have one shot to do this clean. Every other time in history when we got a chance to start fresh, we dragged in the old broken stuff out of habit. Look at America and the metric system. We had a moment. We blew it. Now we're stuck running two measurement systems forever.
Mars is a chance to not do that. So:
No "translation" in daily life. Schools teach the Mars calendar only. Mars news uses Mars dates. Earth dates only show up when colonists are talking to Earth, the way we'd write a date in a foreign country's format on a business letter.
No copied weekday names. Not "Monday through Friday plus a weird weekend." Pick fresh names. Maybe the ten founding crews. Maybe the planets in order. Maybe just numbers. Months too. No "January with a different name." Make new ones.
Count from a real day, not a made-up one. Don't pick a fake birth date for a new religion. Don't pick "the day we landed" and call it Year 1, because then you're back to making up year zeros. Just count sols. Sol 47,329 is the real date. Year 95, Month 8, Week 4, Sol 7 is just the human-friendly version of that one number.
The seven-day week goes. This will be the hardest one. Saturday and Sunday are deep in people's bones. But the seven-day week is just a habit. Ten-sol weeks with two or three rest sols at the end might actually be a healthier rhythm than 5-and-2. Try it.
No Christmas in space. No Easter that floats around tracking a moon nobody can see from Mars. Mars holidays should be Mars holidays. The first crop harvest. The day the first kid was born. A festival when two moons line up in the sky. Make new traditions. Don't xerox old ones.
The honest part
This only works if the first generation does the hard thing.
First-generation Mars colonists will all be born on Earth. They will remember Christmas. They will know what month their birthday was in. They'll feel a pull to keep one foot in both worlds. The clean break will feel cold.
But if they do it, the second generation grows up clean. By the third generation, the Earth calendar feels as foreign as Roman numerals.
If they don't do it, Mars will have two calendars forever, just like America has two measuring systems forever. The window closes fast.
Why this is actually about more than Mars
Here's the bigger thing.
Almost everything in your life runs on a default you didn't pick. The calendar. The keyboard. The week. The measuring system. The legal system. The shape of your work day. Somebody, hundreds of years ago, made a choice. That choice got locked in. Now you live inside it. Every day. Without noticing.
You don't usually get to choose. But sometimes, you start something new. A company. A team. A house. A relationship. A blog. A Mars colony.
When that moment comes, you have a tiny window. You can drag in all the broken defaults. Or you can stop and ask, "what would I build if nobody made me copy what was already here?"
Most people don't ask. They copy. The window closes. The defaults win again.
Mars is the biggest version of this question we're ever going to face. But you'll face a smaller version of it this week.
Will you notice the window when it opens?
