Why Ten Days In October 1582 Never Existed

ED Times
3 min readDec 2, 2022


By Sumedha Mukherjee

All the time machine movies we have ever watched have tried their best to convince us that it is possible to deceive time. But instead it turns out the calendar has already deceived us by wiping out ten days of October of 1582 from existence.

At least that is the impression that people on Twitter got after they scrolled through their phone calendars right back to the year of 1582, and found that ten days in October that year never existed.

These Days Never Existed

A cryptic post apparently originated from Facebook and made its way into other social media platforms. It read, Hence people did go back through time on their calendars- and they found that the month of October in 1582 was unusually short.

The date of October 4 was succeeded by October 15; in other words, ten days were missing. “Bro go to your calendar and go to October of 1582”.

A bunch of tweets sprang up on Twitter where people posted their dumbfounded reactions to these missing days. One user wrote, “Can somebody explain October in the year 1582? Time is not real.”

Another user called it “weird as hell” , and yet another person pointed out that October appears normally like the other months, until you tap on it and ten days disappear. Apparently this is a yearly ritual for the internet to dig up the curious story behind the year, 1582.


Back in 2020, American astrophysicist and science communicator Neil deGrasse Tyson solved this mystery on Twitter. “By 1582, the Julian calendar, with a Leap Day every four years, had accumulated TEN extra days relative to Earth’s orbit. So Pope Gregory jump-started his new and exquisitely accurate calendar by canceling 10 days that year, in which October 4 was followed by October 15”.

The Julian calendar, which was followed in the first and second millennia CE, drifted about one day for every 314 years. Hence by 1582, the vernal equinox, usually followed on March 21, had reached March 11th. To solve this temporal discrepancy and easily calculate the date of Easter, the Council of Trent decreed a solution to the problem in 1562–63.

But it took 20 more years for Pope Gregory XIII to promulgate the reformed calendar- the Gregorian calendar, which is used till today. Hence in 1582, ten days were dropped from October to bring the vernal equinox back to March 21. October was chosen to avoid skipping the Christian festivals. Still, the fact that some days never existed in the history of time is quite trippy.

Originally published at https://edtimes.in on December 2, 2022.