Makara Sankranti’s Astronomical Significance

Makara Sankran­ti is cel­e­brat­ed across the sacred lands of Bhara­ta Var­sha for many cen­turies. This cel­e­bra­tion is also wide­ly con­sid­ered as an Agrar­i­an fes­ti­val. In our cul­ture, this day has been a obser­va­tion of obei­sance to Sun and the soil, grat­i­tude to divine intel­li­gence and life ener­gies, a cel­e­bra­tion of abun­dance and the gifts of nature, ush­er­ing of spring, joy­ous har­vest of puls­es, cere­als and crops and an elab­o­rate offer­ing to Devas from local pro­duce. In this arti­cle we delve into under­stand­ing this cel­e­bra­tion and its sig­nif­i­cance by answer­ing some fun­da­men­tal ques­tions includ­ing — What is Makara? What is Sankaran­ti? What is the sig­nif­i­cance? In this process, we shall also see how nuanced the sci­ences of astron­o­my and math­e­mat­ics thrived in Bhara­ta.

What is Makara?

Owing to the rota­tion of Earth along its tilt­ed axis, we see all celes­tial bod­ies ris­ing in the East and set­ting in the West. This is termed as the diur­nal motion. Also as the Earth revolves around the Sun, the por­tion of the celes­tial back­drop changes through out a year. Through astro­nom­i­cal obser­va­tion, this can be wit­nessed as the Sun’s move­ment across select seg­ments of the celes­tial sphere through­out the year. That is, as the Earth moves around the Sun, the celes­tial object right behind the Sun changes. To our obser­va­tion, it seems like the Sun is mov­ing through the con­stel­la­tions with respect to the celes­tial sphere as a frame of ref­er­ence.

This keen obser­va­tion has played a major role in the Indi­an reck­on­ing of space and time. The fol­low­ing is a verse by revered Indi­an Astronomer Nilakan­tha Somaya­ji (1444–1545 CE) in his path break­ing work Tantrasan­gra­ha [Source: Rama­sub­ra­man­ian, K., and M. S. Sri­ram. Tantrasan­gra­ha of Nilakan­tha Somaya­ji. Springer, 2011.]

In the above verse, the word Jyotis­cakra refers to the appar­ent path traced by the Sun in the celes­tial sphere, as seen from the Earth. This is also referred to as the Bhachakra. This is same as “eclip­tic” in mod­ern spher­i­cal astron­o­my. The time tak­en by the Sun to go around the eclip­tic once, there­by cov­er­ing 360°(cakra), is defined as a Saurab­da, a solar year. What is referred to here is the side­re­al year, which cor­re­sponds to the time inter­val between two suc­ces­sive tran­sits of the Sun across the same star along the eclip­tic. This path of the Sun along the Bhachakra, goes through twelve 30° seg­ments referred as Rashis or Zodi­ac signs. The tenth seg­ment is called Makara Rashi or Capri­corn.

What is Sankaranti?

Sankran­ti is the tran­sit of Sun from one Rashi to anoth­er. Hence the 12 zodi­ac signs cor­re­spond to the 12 Maasas or solar months. Makara Sankran­ti marks the entry of Sun into 0th degree of Makara or Capri­corn zodi­ac. The west­ern cal­en­dars (Julian and Gre­go­ri­an) have no sci­en­tif­ic basis for the alter­ing 30 and 31 days in a month. In the Indi­an cal­en­dri­cal sys­tems, the true posi­tion of the Sun mat­ters. On the ellip­ti­cal path around the Sun, Earth­’s move­ment will be faster near Per­i­he­lion and slow­er dur­ing Aphe­lion. So there would be a few con­tin­u­ous months with rel­a­tive­ly longer dura­tion than the oth­ers. As the Indi­an cal­en­dri­cal sys­tems fol­low the true posi­tions of the Sun, the solar cal­en­dar has num­ber of days accord­ing to the true motion. Earth­’s orbital is cur­rent­ly in a man­ner that we reach the Per­i­he­lion around Jan­u­ary 3 every year.

What is the sig­nif­i­cance?

Cur­rent­ly there are two sig­nif­i­cant phe­nom­e­non asso­ci­at­ed with Makara Sankran­ti — a. sig­nalling the upcom­ing sea­son of spring and b. sig­nalling the onset of Uttarayana. The word “cur­rent­ly” has been con­scious­ly used. We would real­ize why in due course.

The cause for the sea­sons on our plan­et is the tilt of the Earth. The present tilt of the Earth is 23.5° This caus­es vari­ance in the expo­sure to Sun at dif­fer­ent points of the year as Earth moves around the Sun. So we have the equinox­es and sol­stices. We also can observe the south­ward move­ment of the Sun and the north­ward move­ment of the Sun with respect to the car­di­nal East across the year. The peri­od of South­ward move­ment is called Dak­shi­nayana (peri­od from sum­mer to win­ter sol­stice) and north­ward move­ment (peri­od from win­ter to sum­mer sol­stice) is Uttarayana. Owing to the present extent and ori­en­ta­tion of the Earth­’s tilt, these phe­nom­e­na hap­pen clos­er to Makara Sankran­ti. The solar month born on Makara Sankran­ti is the first month start­ing with­in the Uttarayana.

It is also sci­en­tif­i­cal­ly well estab­lished that the extant and ori­en­ta­tion of the Earth­’s tilt has been chang­ing. Imag­ine slow­ly rotat­ing a tilt­ed pen. That is how the ori­en­ta­tion of Earth­’s tilt has been chang­ing. It has been esti­mat­ed that it takes about 25,600 years for the tilt to come back to its same ori­en­ta­tion after a full rota­tion. This phe­nom­e­non is called Pre­ces­sion of Equinox. Present­ly, the north­ern move­ment of the Sun start­ed on the past win­ter sol­stice 22 Decem­ber 2019. In about 72 years, there is a 1° shift in the ori­en­ta­tion, slow­ly caus­ing the dates of equinox­es, sol­stices and the sea­sons to also change. Based on this about 1728 years back, the win­ter sol­stice and the Sun’s entry into Makara would have coin­cid­ed. In about 432 years the win­ter sol­stice would coin­cide with a dif­fer­ent rashi. These fac­tors reveal that Makara Sankran­ti has become an impor­tant phe­nom­e­non for about 2 mil­len­nia. We need to also real­ize that there has been an unbro­ken tra­di­tion of cel­e­brat­ing this phe­nom­e­non of Uttaryana irre­spec­tive of the peri­od of year or month dur­ing which it occurs.

Appreciation for Indian Astronomical Sciences and Mathematics

In Bhara­ta, the pur­suit to refine cal­en­dri­cal cal­cu­la­tions through con­stant obser­va­tions has led to mar­vel­lous meth­ods and algo­rithms to track the true posi­tions of plan­ets, Sun and Moon across the celes­tial sphere. Vara­hami­hi­ra penned the Pan­casid­dan­ti­ka in ear­ly 6th cen­tu­ry by stat­ing that there were ear­li­er 18 sid­dhan­tas but at his time only 5 were extant and to pre­serve them, he took up the onus to doc­u­ment those five. Paita­ma­ha, Vasistha, Roma­ka, Paul­isha and Saura com­prise the five sid­dhan­tas. These works deal with the var­i­ous astro­nom­i­cal prob­lems asso­ci­at­ed with the motion of the Sun and Moon includ­ing their true motion, diur­nal prob­lems, lunar and solar eclipses, as also the motion of the Tara­gra­has i.e. Mer­cury, Venus, Mars, Jupiter and Sat­urn. Start­ing from the plan­e­tary mod­els of Saura Sid­dhan­ta, through thou­sands of years, Indi­an Astronomers and Math­e­mati­cians have con­tin­u­ous­ly evolved meth­ods to pre­cise­ly cal­cu­late the true posi­tion of Sun with respect to the celes­tial sphere on any giv­en instant at any giv­en day.

Our astronomers real­ized through very long peri­ods of data that the equinox­es pre­cess and advo­cat­ed a Nirayana Sys­tem. We need to under­stand deeply that when­ev­er the Earth comes to a par­tic­u­lar point on the orbital, we see Sun come back con­stant­ly to the same Rashi. Where­as the phe­nom­e­na of equinox and sea­sons may vary. The Sayana sys­tem is with rela­tion to Ver­nal Equinox which is a vary­ing phe­nom­e­non. The Nirayana sys­tem is with respect to the Sun’s entry into Mesha. Look for­ward to learn­ing more about this this dur­ing our Indi­an Solar year.

Hence our tra­di­tion­al fes­ti­vals dot­ted through­out our Indi­an cal­en­der, are not only cul­tur­al­ly rich but also are pre­cise­ly marked through the space-time com­plex using the Nirayana sys­tem with the stel­lar con­fig­u­ra­tion as the ref­er­ence points.

TAGS: pon­galsankran­ti

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