#PalindromeDay: Geeks around the world celebrate 02/02/2020
Maths geeks around the world are celebrating a day so rare that - unless they're very, very young - it's certain to happen only once in their lifetimes.
This is, of course, palindrome day, when the date - in this case 02/02/2020 - reads the same way back to front.
But while palindrome days come and go - 20/02/2002 is another example - this one is special.
Unlike the date in 2002, this one reads the same in North America, where dates are written as month-day-year instead of day-month-year as in much of the rest of the world.
It also works for China and a handful of other countries which put the year first.
The last time a palindrome like this happened was 11 November 1111. (Which is really beside the point, because no-one was using Arabic numerals in North America then.)
In that year:
- Crusaders led by Baldwin I of Jerusalem were fighting the Turks in what is now northern Syria
- Henry I, fourth son of William the Conqueror, was king of England
- Afonso I, founder of the kingdom of Portugal, was born
We don't have to wait quite so long for the next international palindrome day, though - it's 12 December 2121. Who knows? Some of us may even live to see it.