My Idd-Ul-Fitr date prediction was correct
The Sunday Nation
Nairobi,
03 August 2014
How do you measure the thickness of a piece of paper using an ordinary
ruler? It’s simple: take the measurement of a large number of papers
then divide. For example; the 2014
The interesting thing about that simple measurement is that one is able to determine the thickness of an object that is a few hundredths of a millimetre using a ruler who accuracy is one full millimetre. The same trick can be used in measuring time…
One of the most common secondary school physics experiments involves timing the swing of a pendulum. It is also probably the most “beautiful” experiment because of its simplicity and the wealth of information it yields.
Using an ordinary stop clock whose accuracy is one second, students are expected to make precise measurements the period of one complete oscillation of the pendulum. To achieve the desired precision, they time the duration for a large number of swings, say 50. This time is then divided by 50 and, voila!
The beauty of this experiment lies in the fact that one can use its data to work out the mass of the earth. If your teacher didn’t show you how to do that, please go back and ask for a refund of school fees: you were swindled!
But the mass of our planet is not my concern at the moment; I am only interested in the method that students all over the world use to accurately measure the period for one swing of a pendulum.
Of all heavenly bodies, I think the moon has been studied for the longest time by astronomers; probably for longer than the sun! Everybody knows that the moon goes through regular cyclic phases. Indeed many ancient cultures used these cycles to create calendars – the most popular in modern times being the Islamic one.
Since the moon’s phases have been observed for thousands of years, the
duration of its cycle is known very accurately – similar to a student
timing several thousand swings of pendulum. The moon cycle takes
29 days, 12 hours,
44 minutes and 2.877 seconds.
Now, on 18th August
last year, I used this cycle time and predicted that, “the new crescent
moon marking the end of Ramadhan in 2014 will be sighted in the evening
of July 27, meaning that Idd-Ul-Fitr will…fall on July 28.”
I was right on
target; Muslims around the country held their Idd celebrations on July
28 even though the public holiday was set for the 29th. How I wish the
authorities had read my article.
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