Makara Vilakku

Makara (Sanskrit: मकर) is the name of a zodiac sign in Indian languages known as Capricorn in English. "Jyoti" means "light" in Sanskrit. Thus "Makara Jyoti" (also spelt as Jyothi) means "Light of Capricorn".

The Sun appears to move from one zodiac constellation to another every month and the day on which Sun changes the constellation is called Sankrānti ("transit") in Sanskrit. Makara Sankranti (Sanskrit: मकर संक्रान्ति, Malayalam: മകര സംക്രാന്തി, Kannada: ಮಕರ ಸಂಕ್ರಾಂತಿ, Tamil: தைப்பொங்கல், Telugu: మకర సంక్రాంతి ) is the Sun’s transit into Capricorn (Makara) constellation that usually occurs on 14 January every year and is a very important Hindu festival celebrated all over India in various forms. Uttarāyaṇa, the six-month period when the sun travels towards the north on the celestial sphere, starts on Makara Sankranti and ends on Karka Sankranti (around July 14).

One of the places where a large number of devout Hindus reach on 14 January for worship is Sabarimala located in thick rain forests of Kerala.

Makara Jyothi is a star which is worshiped by pilgrims in huge numbers at Sabarimala Temple in Kerala on Makara Sankranti on 14 January every year. However many devout Hindus claim that Makara Jyothi is the celestial lighting which takes place on Makara Sankranthi day and they believe that Lord Ayyappan asserts himself as Makara Jyothi to bless his devotees.

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Wikipedia