You can see for yourself: open the calendar on your iPhone, get into the year view and scroll the time to the year 1582. Don’t worry, if you scroll quickly, it won’t take you more than a minute to go through all those centuries. Watch the first week of October this year.
Yeah, something weird is going on. From October 4 we go to 15, the calendar jumps ten days as if nothing had happened. The logic is to think that this is an error that Apple had to let go (no one is going to place events in the 16th century), but no: there is a reason behind this jump and Apple correctly captures it in the calendar.
A cumulative shift of 1600 years, corrected with the stroke of a pen
Some Internet users have noticed it and comment on it on social networks:
A question, in the telephone book we can go until October 5, 1582?
—Luis Pastor (@Luis_pastor) February 19, 2023
This day does not exist. pic.twitter.com/ZktRSrO8T6
— Ponchi (@pontzi) February 20, 2023
Everything lies in the Gregorian calendar that we have been using since precisely the year 1582. It was during this first week that Pope Gregory XIII applied it using his own name, seeking to correct a flaw in the Julian calendar that was used at that time.
Said calendar, implemented by Roman Emperor Julius Caesar (also hence the name) and based on the Egyptian calendar, assumed years had 365 days and six hours
The problem is that this measurement was imprecise. Those “remaining” hours beyond 365 days weren’t 6: they were 5 hours, 48 minutes, and 45 seconds. There was a lag of 11 minutes and 15 seconds which, accumulated over almost 1,600 years, had become a lag of nearly ten days.
Pope Gregory wanted to correct this ten-day shift with the stroke of a pen, and that is what happened at midnight on October 4, 1582: suddenly the date was advanced by 10 days and we went from October 4 to October 15. Days 5, 6, 7, 8 or 10, 11, 12, 13 and 14 October 1582 never existed, and Apple has correctly reflected this fact in its timelines.
