The Science behind Makara Sankranthi & its astrological significance

Contrary to the popular belief, Makara Sankranti is not only a Hindu festival but actually a universal phenomenon because it is purely based on the science of astronomy & crop cycle which is not limited to any particular religion. Basically, it is a celebration of the “revival” of sunlight (solar energy & positivity) into our lives and it coincides with the harvest season as well.
Much before contemporary scientists came up with their observations of solar system a few hundred years ago, scholars of ancient India (5,000 years ago) presumed that sun is the center of our celestial system and is the source of energy for all planets including our planet earth, which takes 365 days to revolve around the Sun. 
This complete cycle of 360 degree which is also called the solar calendar is divided into 12 phases or domains or zodiacs of 30 degree each (360/12=30) and each zodiac is associated with certain characteristic depending on the positions of earth & sun in relative to each other, which in turn also determines the season & radiation patterns.
In other words, it means the zodiac phases of the Sun from July to December witness decreasing sunlight, and after that, the subsequent zodiac phases witness increase in sunlight. 
For an observer, it looks like the Sun is on a downward journey between July to December and this downward journey suddenly changes to upward journey or northward movement in late December & early January. Since uttara means northward & aayana means movement in Sanskrit, this phenomenon of phase reversal from southward movement to northward movement of the sun is called “Uttara Ayana” or “Uttarayan” in short.
If the chart is divided into zodiacs, then we notice that it is Makara which is the first among the series of phases witnessing an upward journey, and this trend continues with subsequent phases till peak summer. Hence, the Makara phase holds such great significance in astronomy because it represents revival of sunlight & energy.
But if Makara is the name of a zodiac, then what does Sankranti mean? In Sanskrit, Sankranti means the entry of Sun into a zodiac phase. Whenever the Sun moves out of one zodiac phase & enter another zodiac phase, such transmigration of the Sun is called a Sankranti. 
Since we have 12 zodiacs in a year, there will be 12 Sankrantis each year. Now that we know how Makara is significant due to the revival of sunlight, the transmigration of Sun into Makara is celebrated as “Makara Sankranti”, which usually falls on 14th of January (or 15th on certain years).
Apart from the astronomical & solar significance, this coincides with the harvest season. Therefore, this is also seen as a celebration of crop harvesting resulting in continuity of food supply which irrespective of our religion, is one of the most basic necessities of our lives. Makara Sankranti is celebrated with lot of pomp and show by many communities throughout India, albeit in different names and slightly varied traditions. 
It is celebrated as Bhogi and Sankranthi in Andhra Pradesh, Pongal in Tamil Nadu, Sankramana in Karnataka and Maharashtra, Lohri in Punjab, Uttarayan in Gujarat, Khichdi in Bihar and Bihu in Assam. Almost all regions in India celebrate this festival, cutting across all castes & creed because it is nothing but a tradition to observe & celebrate the revival of solar energy in our lives. i.e Irrespective of our religion, we all benefit from solar energy.  

Photo Gallery