Acharya Ram Hari Sharma has written a detailed article on "Rituals & Significance of Adhik Maas" on AstroCAMP.com Astrology Magazine, and I am quoting from the article -
“Generally all efforts with the intention of worldly gains are strictly prohibited during Adhika masa as mentioned in scripture and one is advised to follow special rituals for this month. During this period, marriages, tonsures (mundan), inaugurations of new home, fasting with desire of some worldy gains, buying new ornaments and vehicles are prohibited.The detailed article can be found on AstroCAMP.com here - "Adhik Maas 2010: Rituals & Significance."
The month that does not carry Surya Sankranti is called Adhimass and the month carrying two Sankrantis is called Kshayamass. As per Astrological calculations, Adhimass comes after 32 months, 16 days and 4 ghatis and Kshayamaas first arrives after 141 years and then after 19 years.”
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