Sundance (or seen the sun in the sky?)

of course. we all have

let’s take a look at how the sun dances in the sky, over the seasons

pick a location, say Dallas TX, which lies in the northern hemisphere, about latitude 33 degrees north. as we heave ourselves out of winter and prance into spring, the days start lengthening noticeably, certainly by, say around march-april. the sun rises a little earlier each day and sets a little later each day, as spring springs ahead, the sun’s daily zenith climbing higher each day. the point of sun rise, the arc traced by the sun and the point of sunset, all move closer towards the ‘middle’ of the earth each day. until june 20/21st. where the sun has risen as high as it will. when it will shed the most sunlight. it now reverses direction and begins to fall, and, as we head into fall some months later, the days getting shorter with progressively later sunrises and earlier sunsets. the sun’s zenith a little lower each day, the arc a little lower and further away from the ‘middle’ of the earth each day. until december 21/22nd, when it reaches the lowest point with the shortest arc. shedding the least sunlight. completing the cycle which repeats year after year.

and the cycle looks like this

 

 

the sun's graceful dance in the sky

 

the jan-jun growth cycle, my mother tells me, is called Utharrayanam (‘northern’) and the jun-dec waning cycle is called Dhakshinnayanam (‘southern’) in Tamil (with Sanskrit roots)

these pirouettes of the sun are captured beautifully with  multiple exposure photographs

here’s one as the sun traces its daily path on a clear day in december, location someplace UK

 

sun traces arc from morn to nite, december day, from the UK

 

pick a location and a precise repeatable spot for your camera. step outside each day when the sun is at its zenith and photograph the sun while maintaining the same frame day after day. choose some good clear images from the collection (sans clouds etc). take one more pic of the backdrop. put them all together

you get the analemma – sign of infinity – limitless boundless (or the more prosaic figure 8…)

 

northern hemisphere analemma (21.6 = 21st of june)

 

you can tell that this location is in the northern hemisphere from the fact that the small part of the 8 is pointed upwards – it would look inverted if viewed from a location in the southern hemisphere i e the pointy part points downwards and the fat part is up in the sky. other interesting shapes are seen when viewed from locations around the equator or at the poles

here are some very pretty suntracks

 

 

east to west suntracks through the seasons

 

thanks to the following sites for information on the analemma

http://scienceblogs.com/startswithabang/2009/08/why_our_analemma_looks_like_a.php and http://www.analemma.com/Pages/framesPage.html

the sun dances in the sky over the seasons, shifting east west north south, rising in summer and sinking in winter, tracing different apparent location defined paths

the quencher’s energy absorber must point at the sun at all times to suck the maximum amount of energy possible from the sun

if a stationary and immovable absorber were to collect X energy in a day, a single axis tracker, i e a tracker that tracks the sun daily from east to west, can collect up to 1.3 X energy

a 2-axis tracker will also track the slower north-south movements, a little change each day as the seasons shift. the quencher’s user will perform this simple small daily north south 2nd axis adjustment manually, making sure to collect all the energy that can possibly be collected

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About Vishwa Narayan

who can live without water? drinking water for all is my goal, through Theertham, a not-for-profit organization i founded and registered in Texas. you can reach me at drvishwanarayan@yahoo.com
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