Well I am guessing it maybe something to do with a 555 timer chip......
Although the original chip came out in 1971, there are now CMOS and high tech versions around.
The timing function is calculated as t=RxC, so if they use a 1Meg resistor and 1 microfarad capcitor you get 1 second...... so I am guessing that is 555 seconds.... just over 9 minutes.