Lamp of the Determination of Lunar Days

A solar month Saura: A month measured by the sun's movement through one sign of the zodiac. exists from one transit to the next, while the civil month Savana: A standard 30-day month used for practical or administrative purposes. is declared to consist of exactly thirty days by the authors of the Brahma-Siddhanta original: "brahmasiddhāntakartṛbhiḥ". Refers to the ancient astronomical treatise or its followers.. || 21 ||

The duration during which the Sun original: "Bhāskara" wanders through the constellations starting with Ashvini Ashvini: The first of the 27 Nakshatras or lunar mansions in Indian astronomy. is known as a sidereal month Nakshatramasa: A month based on the moon's or sun's position relative to the fixed stars.; this is our declaration for the sake of religious duty. || 22 ||

In a year where a month occurs without a solar transit original: "saṃkrāntirahito māso". This happens because the lunar month is shorter than the solar month., there will be two [months of the same name]. || 23 || Of these, the first is to be utilized under the name of the preceding month. It is also known by the name Samsarpa original: "saṃsarpa". Literally "the crawler", a name for an intercalary month., while the second is the intercalary month Adhimasa. || 24 ||

It is also to be known by the name Malimlucha original: "malimluco". Literally "the stained" or "impure one", so called because this extra month is considered unfit for major religious festivals or sacraments., a name that implies it is forbidden for ritual acts. Starting from a previous intercalary month, after thirty-two months, sixteen days, and four units? The text likely refers to 32 months, 16 days, and 4 Ghatis (24-minute units), the standard interval between intercalary months. have passed, it occurs again. || 25 ||

A month joined with two solar transits original: "saṃkrāntidvayayuktastu". This rare occurrence happens when two solar transits occur within the span of a single lunar month. is to be known as a suppressed month Kshayamasa: Literally a "wasted" or "lost" month that is dropped from the calendar to correct the alignment.. || 26 || This is also referred to by the name Brihaspati original: "bṛhaspatira-nenāpi". Brihaspati is the name for the planet Jupiter; here it likely refers to a specific calendrical calculation.. This suppressed month occurs only among the three months beginning with Kartika October/November. The sun's apparent motion is fastest during this time, making a double-transit month possible.. || 27 || There, [it is said]... catchword: "tatra māra"

Ref: Mu Prakriyavinah 574