How to Time the North Star

Locate the Big Dipper in the clear night sky. Follow the line of the two stars that form the outer part of the bowl to locate the north star.

Imagine that the two stars on the outer bowl of the Big Dipper are the hand of a giant star clock that has a 24-hour face, rather than a 12-hour face. This clock runs counter-clockwise as the Big Dipper circles in that direction around the North Star. The 12 o'clock position on a normal clock would be midnight on this star clock. The 9 o'clock position is 6 a.m. on the star clock, the 6 o'clock position is noon on the star clock and the 3 o'clock position is 6 p.m. on the star clock.

Calculate how many months past March 6 the date is, using 1/4 month intervals. The star clock described in step two is as it appears on March 6 each year. As the year passes, the star clock face, itself, rotates. Always use the number of months past March 6 your current date is. Thus, February 6 would be 11 months past, not 1 month before. The number of how many months past March 6 your date is will be used in the formula to determine the current time.

Read the star clock as if it were March 6. Say that the clock is in the 13 position. (Remember, this is a 24-hour clock that runs backward, so the 13 position would be midway between the 5 and the 6 o'clock positions on a normal clock face).

Pretend that this reading is being taken on September 6, six months after March 6. The formula for determining the current time is, the time on the star clock as if it were March 6, minus the sum of two times the number of months past March 6. In this case, the formula can be written as: 13 - (2 x 6) = 1. Positive numbers reflect the hours past midnight. Negative numbers reflect the hours before midnight.The current time in this example is 1 a.m. If you pretend the reading is being taken on October 6, seven months after March 6, the formula is: 13 - (2 x 7) = -1, or 11 p.m.