Tuesday, October 11, 2022

March Forth Equiknocks!

 As a person interested in simple astronomy, I always watch the sun on the four important days of Earth's revolution around it - the two solstices and the two equinoxes.

By keen observation of polaris from my childhood days when it was easily visible in the relatively clean days of those vehicle-pollutionless yesteryears, I have known not only that the north pole is not exactly aligned to the horizon (in which case it would be invisible), but is a little, 23 and a half degrees to be exact, above the horizon, but also tilted slightly to the left of my house plot's north-south alignment.

Therefore, when I am on the terrace for my morning walk, I know that the sun would rise a little left of the east-west alignment of my house on the days of equinox. 

This year it occurred to me that I should record the exact measure of misalignment for posterity, and hence have been continuously monitoring the southward shift of the sun from August onwards. Having noted the position on September 22, the day of autumnal or fall equinox for northern hemisphere, I was keeping a count of the number of days from equinox for the sun's alignment with the east-west walls of my house.  

Unfortunately, the last few days, more than a week let's say, have been cloudy and overcast, and especially covered with dense clouds around the horizon, making it impossible for me to view the sun or note its position and measure the misalignment. 

The air got clear only today, and I found that sun has just crossed its my-house-equinox line yesterday, as today it was just a tad to the right of my parapet wall running east-west. It would certainly have been nice to have had it firmly established yesterday had it been a clear day.

So, I want to record it here that our house is alignned 18 days, or about 4.7 degrees, to the right of Earth's east-west axis! The math is 23-1/2 degrees takes 3 months, so roughly a little less than 8 degrees for one month, and hence about 4.7 degrees in 18 days.

I now have to verify this on the next occasion  the Equum knocks on my door again, which will be 18 days before the equinox, I.e. on or around 4th March next year. Shall I call it March Forth?!

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