Tracking Time: The Julian to Gregorian Calendar Transition Explained | Neil Degrasse Tyson #1159

Join Neil deGrasse Tyson on the Joe Rogan Experience as he delves into the fascinating history of the Julian and Gregorian calendars. Discover how the leap day and the subtle differences in tracking Earth's seasons led to the need for calendar modifications. Learn about the role of Jesuit priests in developing the accurate and widely-used Gregorian calendar, including the bold move of removing ten days from the calendar. Gain insights into the astronomical considerations and the significance of timekeeping in this thought-provoking discussion.

[november]

Imagine you have an assignment due in 11 days and now it's due tomorrow 😂😂

[exatasdev]

for context, joe asked what was tyson's birthdate

[kenarbes]

Isaac Asimov wrote that he lost some days when Russia changed calendars. He wanted those days back.

[YTRulesFromNM]

The Vernal Equinox was originally April 1st and that was the beginning of the year. People that believed the year should start at the Vernal Equinox were called April Fools. No, I'm not kidding. This really happened.

[georgegreene]

He's explaining that entirely wrong. The amount of time it takes us to go around the sun and return to the same solstice (or equinox) iS EXACTLY one year BY DEFINITION and the seasons last EXACTLY the length of time between a solstice and an equinox BY DEFINITION. The reason for the drift from Julian to Gregorian was simply that the number OF ROTATIONS of the planet during that constant/defined time IS NOT exactly 365&¼. It's A LITTLE LESS than that -- so every 20th qudrennium or so, you DON'T need a leap day. Over the intervening millennium, the Julian calendar had had 10 too many, so they came up with a more complicated rule to have 9 fewer -- per millennium.

[matthewhegarty]

And because of that change, my wife (born on Feb 29th) and mother-in-law have battled for 39 years over what day to celebrate my wife’s birthday on non-leap years.

[Telssa]

I figured out how to do the Rain Man's day of the week trick, for the Julian and the Gregorian from 01/1/0001 onwards. Takes me a second or two.
There's a challenge for anyone who fancies it.

[Leisurelee]

fun fact. Julius Caesar was poltifex maximus while on campaign in Gaul. his office was responsible for tracking and correcting the then calendar to account for these known discrepancies. it was so jacked up even before he took office and then neglected it to go on his adventures, that part of why he was able to so quickly take Rome was the senate thought it was still the end of winter and not the beginning of spring.
one of the first things Caesar did as dictator was bring a famous mathematician from Alexandria and create the Julian calendar.
bro exploited the game then immediately patched it.

[theMightyWhytey]

No, the biggest change in the Julian calendar was that the Pontifus Maximus (who at that time was Julias Ceasar) couldn't add days in for political reasons (Ceasar was a master at this), because it hurt the calendar.

[EJL]

They looked at everything from the sun to the moon and the stars, ignored it all and called it the gregorian calander

[PvblivsAelivs]

Moved January and February to the front of the year. Got rid of intercalary months. I believe it also adjusted the length of the months.

[maxberntsen]

What about the original 10 months?
Sept=7
Oct=8
Nov=9
Dec=10
Julius Augustus Caesar…. July August

[hlpever]

Here he goes again. Mr overdramatic who tries to shock us with simple facts that we learned in junior high school if we paid attention.

[Egilhelmson]

The Roman calendar with which Julius Caesar started was legally alterable by Senate vote at whim; a good month according to the pontiffs (a group of politically connected priests, of which Caesar had become the leader, the Pontifex Maximus) might be extended by vote, and a month of Ill fortune shortened. Neil forgot to mention the longest year ever, when the Roman mess of a calendar had to catch up to its “correct” settings, which was over 400 some days long. Apparently the pontiffs kept playing around with the leap day, and so it took until about 24 BC before things reverted to Julius Caesar’s original plan.

[KravMagoo]

I have a question. I don't watch or listen to JRE, except on YT. One thing I do know is that NDT is on the show A LOT. Does Joe have a Tyson Tuesday or something?

[chodeshadar]

the Jewish calendar has been adding a leap month according to a certain schedule, because Exodus says Passover must always fall in the spring. This has been in use for about 2000 years.

[thethirdjegs]

It is easier to explain that the julian calendar has too many leap years because 1 year is not equal to 365.25 days. That slight difference in the hundredths place is enough for the julian calendar to be 1 day out of sync every (less than) 400 years.

Now the gregorian calendar do not make leap years in the years that ends with 00 but are indivisible by 400.

[bradfordrusso]

Your omniscient perroration is idiotically illogical. OF COURSE the cyclic orbit and the seasons co-incide. Careful listening to your exact words reveals NO stated difference between Julian and Gregorian. You incorrectly indicate that Julian DID have "leap year". But you make No mention of the day every 400 years.

[anudeep]

If we take other calendars as reference hard to calculate ecclipses timings accuracy....future astronomical predictions...in accurate
gregorian calendar only accounts the leap years and timings...
(only who knows about time can understand this)

[accountforcommenting]

Can you make video on other calenders, like the one we use in India😊