In less than few hours from now we will experience one of the most beautiful moments in the life of earth and its inhabitants. This instant occurs once a year in the northern hemisphere and is called the Spring solstice (Autumn solstice in southern hemisphere), Persians celebrate that one instant that heralds the beginning of the season of re-growth in nature, the Spring, and call it Saal Tahvil (year change).
Saal Tavil is the moment when the old Persian solar year is changed to the new year. Unlike the Christian year that begins at midnight at the end of the last day of December and therefore is a relative moment depending on where one lives in the world, the Persian new year begins at a time which is universally at the same moment all over the world. This brings us to the first set of question:
1. What does this time signify?
2. How is it calculated?
3. Why does it occur at the same instant around the globe?
4. Why does it change from year to year?
Every year Tehran university’s Institute of Geophysics computes or as they say, ‘extracts’, this time for the nation. If the calculated time is before the real noon then the same day is declared as the first day of Farvardin and the first day of the new year. If the calculated time occurs after the real midday, then the next day is declared as the first day of the new year.
There are a number of interesting phenomena attributed to the moemnt of Saal Tahvil which brings us to the puzzle:
5. What do the gold fish do in the instant of Saal Tahvil and why?
And now the trick: couple of minutes before the Saal Tahvil. pick up an egg and choose a wall or any medium sized mirror. Place the egg from its narrow or the wide end on the mirror and hold it vertically. At the moment of Saal Tahvil relax your hold on the eggg, and it should remain upright. It works believe me I have tried it. This brings us to the penultimate question:
6. Why does the egg in the above trick remains upright after Saal Tahvil.
7. How does Saadi describe Saal Tahvil?
The winner is whoever that answers most or all of the above questions correctly. The prize will be a surprise!