Appendix:Hindu units of measurement

Old Indian measures are still in use today, primarily for religious purposes in Hinduism and Jainism. They also are employed in the teachings of Surat Shabda Yoga.

Time
The Hindu metrics of time (Kaala Vyavahara) can be summarized as below.

Sidereal metrics

 * a Lipta (लिप्ता) is approximately 0.4 seconds
 * a Vighati (विघटि) is 60 Liptas, or approximately 24 seconds
 * a Ghadika (घटि) is 60 Vighatis, or approximately 24 minutes
 * a Muhurta is equal to 2 Ghadikas, or approximately 48 minutes
 * a Nakshatra ahoratram (नक्षत्र अहोरत्रम्) or sidereal day is exactly equal to 30 Muhurtas (Note: A day is considered to begin and end at sunrise, not midnight.)

An alternate system described in the Vishnu Purana Time measurement section of the Vishnu Purana Book I Chapter III is as follows:


 * 100 Truti = 1 Tatpara
 * 30 Tatpara = 1 Nimesha
 * 15 Nimeshas = 1 Kásht́há
 * 30 Kásht́hás = 1 Kalá
 * 30 Kalás = 1 Kṣaṇa
 * 12 Kṣaṇa = 1 Muhúrtta
 * 30 Muhúrttas = 1 day (24 hours)
 * 30 days = 1 month
 * 6 months = 1 Ayana
 * 2 Ayanas = 1 year or one day (day + night) of the gods

Small units of time used in the Vedas

 * a Trasarenu is the combination of 6 celestial atoms.
 * a Truti is the time needed to integrate 3 Trasarenus, or 1/1687.5th of a second.
 * a Vedha is 100 Trutis.
 * a Lava is 3 Vedhas.
 * a Nimesha is 3 Lavas, or a blink.
 * a Kshanas is 3 Nimeshas.
 * a Kashthas is 5 Kshanas, or about 8 seconds.
 * a Laghu is 15 Kashthas, or about 2 minutes.
 * 15 Laghus make one Nadika, which is also called a danda. This equals the time before water overflows in a six-pala-weight [fourteen ounce] pot of copper, in which a hole is bored with a gold probe weighing four masha and measuring four fingers long. The pot is then placed on water for calculation.
 * 2 Dandas make one Muhurta.
 * 6 or 7 Dandas make one Yamah, or 1/4th of a day or night.
 * 4 Praharas or 4 Yamas are in each day or each night.

Lunar metrics

 * a tithi (also spelled thithi ) or lunar day is defined as the time it takes for the longitudinal angle between the moon and the sun to increase by 12°. Tithis begin at varying times of day and vary in duration from approximately 19 to approximately 26 hours.
 * a paksa (also paksha) or lunar fortnight consists of 15 tithis
 * a masa or lunar month (approximately 29.5 days) is divided into 2 pakshas: the one between new moon and full moon is called gaura (bright) or shukla paksha; the one between full moon and new moon krishna paksha
 * a ritu is 2 masa
 * an ayanam is 3 rituhs
 * a year is 2 Aayanas

Tropical metrics

 * a Yaama (याम) = 1/4th of a day(light) or night [ = 7&frac12; Ghatis (घटि) = 3&frac34; Muhurtas (मुहूर्त) = 3 Horas (होरा) ]
 * 4 Yaamas 1 half of the day (either day or night)
 * 8 Yaamas 1 day (day + night)
 * an Ahoratram is a tropical day (Note: A day is considered to begin and end at sunrise, not midnight.)

Reckoning of time among other entities

 * Reckoning of time amongst the pitrs.


 * 1 human day = 1/30 day of the pitrs
 * 30 days of human is 1 month of human = 1 day of the pitrs
 * 12 months of human = 12 days of the pitrs
 * The lifespan of the pitrs is 100 years of the pitrs (= 3,600 human years)


 * Reckoning of time amongst the Devas.


 * 1 human year = 1 day of the Devas.
 * 30 days of the Devas = 1 month of the Devas.
 * 12 months of the Devas = 1 year of the Devas
 * The lifespan of the Devas is 100 years (= 36,000 human years)

The Vishnu Purana Time measurement section of the Vishnu Purana Book I Chapter III explains the above as follows:


 * 2 Ayanas (six month periods, see above) = 1 year or one day (day + night) of the devas
 * 360 days of the devas = 1 year of the devas
 * 12,000 years of the devas = 4 Yugas


 * Reckoning of time for Brahma.


 * 12,000 years of the Devas = 1 day of Brahma (4320,000,000 human years). This day is divided into 10, 000 parts called charanas. The charanas are divided as follows:

The cycle repeats itself so altogether there are 1000 cycles of yugas in one day of Brahma.


 * One cycle of the above four yugas is one mahayuga (4.32 million solar years)
 * A manvantara consists of 71 mahayugas (306,720,000 solar years). Each Manvantara is ruled by a Manu.
 * After each manvantara follows one Sandhi Kala of the same duration as a Krita Yuga (1,728,000 = 4 Charana). (It is said that during a Sandhi Kala, the entire earth is submerged in water.)


 * So, the day of Brahma equals: -


 * (14 times 71 mahayugas) + (15 x 4 Charanas)


 * = 994 mahayugas +  (60 Charanas)


 * = 994 mahayugas + (6 x 10) Charanas


 * = 994 mahayugas + 6 mahayugas


 * = 1000 mahayugas


 * as is confirmed by the Gita statement "sahasra-yuga paryantam ahar-yad brahmano viduh", meaning, a day of brahma is of 1000 (maha-)yugas. Thus a day of Brahma, kalpa, is of duration: 4.32 billion solar years. Two kalpas constitute a day and night of Brahma


 * 30 days of Brahma = 1 month of Brahma (259,200,000,000 human years)
 * 12 months of Brahma = 1 year of Brahma (3,110,400,000,000 human years)
 * 50 years of Brahma = 1 parardha (155,520,000,000,000 human years)
 * 2 parardhas = 100 years of Brahma = The lifespan of Brahma (311,040,000,000,000 human years)

The Vishnu Purana Time measurement section of the Vishnu Purana Book I Chapter III explains the above as follows:


 * 360 days of the gods = 1 year of the gods
 * 12,000 years of the gods = 4 Yugas
 * 1,000 sets of 4 Yugas = a day of Brahma
 * 50 years of Brahma = 1 Pararddham/parardha
 * 100 years of Brahma = 1 Param


 * 4,000 + 400 + 400 = 4,800 years = 1 Krita Yuga
 * 3,000 + 300 + 300 = 3,600 years = 1 Treta Yuga
 * 2,000 + 200 + 200 = 2,400 years = 1 Dwapara Yuga
 * 1,000 + 100 + 100 = 1,200 years = 1 Kali Yuga


 * Alternately, the reigns of 7 Rishis, Indra and Manu = 1 Manwantara(excluding sandhikalas) = 71x12,000(excluding sandhikalas) = 852,000(excluding sandhikalas) years of the gods
 * 14 Manwantaras + 15 sandhikalas = a day of Brahma

Vedic Time Units greater than a Kalpa
Ancient vedic cosmology takes into account handful of time spans which are even greater than one Kalpa or a day of Brahma. One such unit is a "Maha-Kalpa" which is composed of 36000 such days of Brahma. One Maha-Kalpa is considered as the lifetime of Brahma. There are time units which are larger than one Maha-Kalpa. The largest of them has been calculated as several quadrillions of human years. This precise and massive calculations indicate one important aspect of vedic time system, that, whenever the term "Infinity" has been mentioned in Vedas, it does not indicate something very large. Instead, it appears that the term is meant to refer its literal synonym itself. [Source]