August 30, 2016 Tuesday
Meeting with Mr. Merchant cancelled.
Can you guess why?
Our IO overslept.
Bedtime Story
Don't you wish to know who was the first ape amongst our ancestors who used the idea of parallax to calculate the distance of a nearby star?
Well...First let me tell you the difficulty with this process.
The universe is so vast and the stars such distances away that the triangle we would make even at different positions of the earth from sun (maximum being 6 months apart when earth is at the opposite ends of sun) tends to subtend extremely small parallax angles.
So small that our conventional degree works out to be very large.
To overcome this hurdle, the unit used is arc second.
What is this arc second?
We know that 1 degree is 1/360 of a turn.
1 arc minute is 1/60 of a degree.
1 arc second is 1/60 of an arc minute.
This works out to 1/3600 of a degree or 1/1,296,000 of a turn.
To give you a perspective how small 1 arc second is.
The 6/6 letters in our Snellen chart at a distance of 6 metres subtend an angle of 5 arc minutes (individual limbs of letters subtend 1 arc minute).
A small coin kept at a distance of 4 kilometres would subtend an angle of 1 arc second.
The nearest star to our sun is Proxima Centauri.
It has a parallax of a meager 0.7687 +- 0.0003 arc seconds.
In fact the stellar parallaxes are so minute that in the early days of enlightenment due to its apparent absence it was used as an argument AGAINST heliocentrism.
The orbital distance of the earth around the sun is about 150 million kilometers that has been adopted as 1 astronomical unit or 1 AU.
In spite of this Herculean task of measuring such minute angles over months and years, a German astronomer, mathematician and physicist by the name of Friedrich Bessel did make this breakthrough in 1838.
That year he announced the parallax of the binary star 61 Cygni to be 0.314 arc seconds and using the known earth's orbital radius calculated its distance to be 10.3 light years.
The flood gate to the heavens were opened by a mathematician.
Stay tuned to the voice of an average storytelling chimpanzee or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
Meeting with Mr. Merchant cancelled.
Can you guess why?
Our IO overslept.
Bedtime Story
Don't you wish to know who was the first ape amongst our ancestors who used the idea of parallax to calculate the distance of a nearby star?
Well...First let me tell you the difficulty with this process.
The universe is so vast and the stars such distances away that the triangle we would make even at different positions of the earth from sun (maximum being 6 months apart when earth is at the opposite ends of sun) tends to subtend extremely small parallax angles.
So small that our conventional degree works out to be very large.
To overcome this hurdle, the unit used is arc second.
What is this arc second?
We know that 1 degree is 1/360 of a turn.
1 arc minute is 1/60 of a degree.
1 arc second is 1/60 of an arc minute.
This works out to 1/3600 of a degree or 1/1,296,000 of a turn.
To give you a perspective how small 1 arc second is.
The 6/6 letters in our Snellen chart at a distance of 6 metres subtend an angle of 5 arc minutes (individual limbs of letters subtend 1 arc minute).
A small coin kept at a distance of 4 kilometres would subtend an angle of 1 arc second.
The nearest star to our sun is Proxima Centauri.
It has a parallax of a meager 0.7687 +- 0.0003 arc seconds.
In fact the stellar parallaxes are so minute that in the early days of enlightenment due to its apparent absence it was used as an argument AGAINST heliocentrism.
The orbital distance of the earth around the sun is about 150 million kilometers that has been adopted as 1 astronomical unit or 1 AU.
In spite of this Herculean task of measuring such minute angles over months and years, a German astronomer, mathematician and physicist by the name of Friedrich Bessel did make this breakthrough in 1838.
That year he announced the parallax of the binary star 61 Cygni to be 0.314 arc seconds and using the known earth's orbital radius calculated its distance to be 10.3 light years.
The flood gate to the heavens were opened by a mathematician.
Stay tuned to the voice of an average storytelling chimpanzee or login at http://panarrans.blogspot.in/
Good night mon ami and my fellow cousin ape.
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