The Mridangam is an acosutic double sided drum like instrument always used in Carnatic music performances. This instrument has all the characteristics of Makar rashi and Shani Maharaj. Let us see how.
First of all it is an ancient instrument often depicted on sculptures, paintings, wood work and mythology. It is the instrument of choice for Ganesha and Nandi. It is hollow inside with air in it and Shani rules over Vayu tattwa. It is a percussion instrument where it is beaten/struck or scraped by the artist, similar to the nature of Shani who represents the down trodden/beaten/ often blamed people. It is traditionally made by hand and laborious to make it. The artist usually places the instrument on his legs and ankles representing Makar and Kumbh rashis of the Kala Purusha.
There are three nakshatras in the Makar rashi. Uttarashada, Shravana and Dhanishta. The Mridangam is made out of Jack Fruit tree wood by hollowing it out. Uttarashada is ruled by Surya and whose ego is hollowed out by Shani and Uttarashada is represented by Jack Fruit tree (see Nakshatra Vana reference below). After hollowing it out the sides of the instrument are covered by Goat or Buffalo skins. The aperture in the middle is anointed by Iron Oxide. The skins are tied/braided with ropes made out of Buffalo skin. Both Goat/Buffalo skins and Iron are signified By Shani. It is said that the sounds made out of the Mridangam pleased Lord Shiva when it was played by Nandi and it is known as a “Divine Instrument”. This signifies Shravana nakshatra the star of hearing. And in Jyotish the symbol associated with Dhanishta nakshatra is a drum and flute again hollow acoustic (Vayu tattwa) instruments. The akshar “Ma” is ruled by Shani which is the starting letter of this beautiful instrument.
I am pretty confident that Makar Rashi and Shani Maharaj play an important role on the charts of famous Carnatic Mridangam artists of the past, but that is for another day.