Hot on the heels of “1234567890” day comes Square Root Day. This rare “holiday” occurs when the day and the month are both the square root of the last two digits of the current year. So, today can be expressed as 03/03/09 (in Europe or the U.S., for once!). 3 is the square root of 9, so you can see how today would be Square Root Day. The last Square Root Day was (quite obviously) in 2004 … 2/2/04 or Groundhog Day, in fact. The next one is 7 years off in 2016 or 4/4/16. While there’s no luck or superstition