After some messing around with strtotime() in PHP I noticed that it gives a valid timestamp back when you pass in spaces and or dots.
var_dump(strtotime(" "));
var_dump(strtotime("."));
var_dump(strtotime(". .. .. .. .... .. . .. ."));
produces:
int 1443009652
int 1443009652
int 1443009652
Why does PHP see this as valid?