For some the 1st of January is no special day; it is like any of the other 365 days. For historical and religio-cultural reasons, the 1st of January has come to signify the start of the year. Not all calendars count the beginning of the year on the same date; the underlying religion behind those calendars determine when the new year starts. However, to keep things simple and synchronised, we have to follow the same calendar – in this case, the Gregorian one. And so, internationally we recognise the 1st of January as the start of the new year.
But on a much larger scale those mundane dates do not hold much significance. The Earth has been here for some 4.5 billion years and it has gone round the Sun for about 4.5 billion times. For what is a year but the duration of the Earth’s trip around the Sun? This cycle is regular but not necessarily precise. There are some discrepancies which make it such that the time the Earth takes to revolve is not always the same. Also, the orbit the Earth traces an elliptical path – not a circular one. This implies that there are two distinct points in the orbit: one where the Earth is at its furthest from the Sun and the other where it is at its closest – position 1 and 2 respectively in the diagram below where the Sun is located in position 3. The point where the Earth is at its closest is called its perihelion while the opposite term is aphelion.
The New Year, as such, could have been defined whenever the Earth is at its perihelion. This would have been a neat way to set our calendar to. But unfortunately the Earth’s perihelion varies each year. This year it will fall on the 2nd of January at 04:38 GMT. Last year it was around half-past midnight (GMT) on the 5th of January. As a matter of fact, the perihelion can be anytime between the 2nd and 5th of January. As for the aphelion it can be anytime between the 3rd and 6th of July. This year it will be on the 5th of July at 14:44 GMT.
As the Earth approaches its aphelion, let me wish you all the very best for the year ahead and let us reflect on our actions for what goes around comes around…
Happy New Year 2013!