The Aryavarta consciousness1 which dominated the Bharatvarsha in its materialistic and spiritual sphere of life led to many great discoveries which inter-alia included origin, theory and order of weekdays.

The origin and definite sequence of weekdays is not based on any labyrinthine concoctions but has its genesis in the womb of ancient Indian science “Jyotish shastra” (astrology) often described as the eyes of the “veda”/ “vedapurusha” 2. Although many historians have attributed the origin of this concept of weekdays to ancient Sumerians3, Babylonian, Greek and Egyptian civilizational sources which dates no older than 2100 BCE but this can be easily refuted by quoting and bringing older Bhartiya text out of terra incognito. Pertinent to mention are the texts of rig vedic age like Suryasiddhanta (taught to Maya-asura by lord Surya himself in Kriti-yuga), Pulatsaya samhita (written by maharishi Pulatsaya ), Prashar samhita and Hora shastra by maharishi Prashara and Srimad Bhagwatam (written by maharishi Krishana dwipayan ved vyas in later vedic period ) . It is important to note here that rig veda is dated nearly 3000 BCE by various scholars and historians but we Indians consider it to be tens of thousands if not hundred-thousand-year old4. Although there also exists long list of other post Christ era texts like Aryabhatiyam by Aryabhata, Panchsidhhantika of Varahmihira , kalmadhava by Madhvacharya ,Siddhant shiromani by Bhaskarcharya to name a few.

Theory and Order

Indian astronomers (siddhant jyotishi / khagol shastri) knew the Heliocentricity of the solar system before the Kepler’s Theory of Heliocentricity (1617-1621) which can be established by the facts mentioned in Aryabhatiyam (4th CE), Panchhsidhantikka (5-6TH CE ), Grahaganit (9TH CE ). However, while calculating the order of the day one needs to follow geocentric method. This is because we live on planet earth if we follow heliocentricity we will get Earth-Day instead of Sunday and Moon-day/Monday will get omitted altogether. To avoid this very error we follow geocentric model.

One may get bewildered that as per vedic astrology we have 9 planets (pind) but we have 7 days, the reason is Rahu and Ketu are considered to be lunar nodes not planets. To determine the order of weekdays one needs to know two things: the first being speed of rotation of planets and the second being Hora (a Sanskrit word derived from another Sanskrit word Ahoratra meaning a complete Day). One ahoratra has 60 ghatis which is equal to 24 horas which corresponds to nearly 24 hours.

To get the sequence of weekdays one must first arrange the planets from slowest to fastest (according to their speed of rotation). The order comes out to be Saturn (shani), Jupiter (guru), Mars (mangal), Sun (ravi), Venus (shukr), Mercury (buddh), and Moon (som). And afterwards he/she needs to make the list of hours from 1st to 24th in a row and then start assigning each hour a graha/planet starting with Saturn, followed by Jupiter, Mars, and so on as mentioned above in the order of their rotation velocity. When one reaches the bottom, that is the 24th hour, one will get Mars (mangal) as per order. Carry over to the next row following this very sequence starting with 1st hour again up to 24th hour. Doing so up to seven times, one will get 7 rows with the 1st hour of each row represented by its dinpati. Therefore, the first row will have Saturn (shani) in its 1st hour, which is also its dinpati. In the second row’s 1st hour one will have sun (ravi), which is the dinpati of the 2nd row. In the 3rd row’s first hour one will have moon (som), which is also the dinpati of the 3rd row. In the 4th row’s first hour, the person will get Mars (mangal), which is the dinpati of the 4th. In the 5th row’s first hour, he/she will have Mercury (buddh), which is the dinpati of the same row. In the 6th row’s first hour, one will have Jupiter (guru), which is the dinpati of the same row. And in the 7th row, the person will get Venus (shukr) at its first hour, which is the dinpati of the 7th row. Then we will arrange the planets/dinpati of all rows in a sequence, and we will get our sequence of weekdays which is shanivaar, ravivaar, somvaar, mangavaar, buddhvaar, guruvaar, and shukrvaar.

Hours

1	Shani	Ravi	Som	Mangal	Buddh	Guru	Shukr
2	Guru	Shukr	Shani	Ravi	Som	Mangal	Buddh
3	Mangal	Buddh	Guru	Shukr	Shani	Ravi	Som
4	Ravi	Som	Mangal	Buddh	Guru	Shukr	Shani
5	Shukr	Shani	Ravi	Som	Mangal	Buddh	Guru
6	Buddh	Guru	Shukr	Shani	Ravi	Som	Mangal
7	Som	Mangal	Buddh	Guru	Shukr	Shani	Ravi
8	Shani	Ravi	Som	Mangal	Buddh	Guru	Shukr
9	Guru	Shukr	Shani	Ravi	Som	Mangal	Buddh
10	Mangal	Buddh	Guru	Shukr	Shani	Ravi	Som
11	Ravi	Som	Mangal	Buddh	Guru	Shukr	Shani
12	Shukr	Shani	Ravi	Som	mangal	Buddh	Guru
13	Buddh	Guru	Shukr	Shani	Ravi	Som	Mangal
14	Som	Mangal	Buddh	Guru	Shukr	Shani	Ravi
15	Shani	Ravi	Som	Mangal	Buddh	Guru	Shukr
16	Guru	Shukr	Shani	Ravi	Som	Mangal	Buddh
17	Mangal	Buddh	Guru	Shukr	Shani	Ravi	Som
18	Ravi	Som	Mangal	Buddh	Guru	Shukr	Shani
19	Shukr	Shani	Ravi	Som	Mangal	Buddh	Guru
20	Buddh	Guru	Shukr	Shani	Ravi	Som	Mangal
21	Som	Mangal	Buddh	Guru	Shukr	Shani	Ravi
22	Shani	Ravi	Som	Mangal	Buddh	Guru	Shukr
23	Guru	Shukr	Shani	Ravi	Som	Mangal	Buddh
24	Mangal	Buddh	Guru	Shukr	Shani	Ravi	Som

As knowledge migrated out of bharat-varsha so does names got changed according to local languages as was the case of ravi-vaar which became sunday as anglo-saxons called surya as sun.

Another question might arise when the new day begins? As far as beginning of the day is concerned it is upto the discretion of jyotishi or ganitagya or mathematician to choose. As Suryasiddhanta mentions new day starts after midnight the sytem which west follows or it can be from one sunrise to another as mentioned in Pulatsya samhita ,Aryabhatiyam,Panchsiddhantika inter-alia.

We as bhartiyas must be proud of our heritage as our ancient erudite maharishis gave the world the most pertinent part of chronology without which human’s scientific endeavour and management of vital activities wouldn’t have been possible.

Let’s us claim what is ours and decolonialise ourselves from the silhouette of west and reinvigorate in ourselves the “aryavarta consciousness” and be the torch bearer to the world by being Vishwa-Guru as we had been for past 3/4th history of mankind.

- Shubhang Raina

References:

• 1. K.M Munshi, Foreword, ”The history and culture of the Indian people, Vol.5,viii .
• 2. Mundako-upanishad (1/1/5).
• 3. Michaelis, Anthony R. "The Enigmatic Seven" (PDF). Interdisciplinary Science Reviews. 7: 373.
• 4.Rig Veda aged 4500BCE and 22000 BCE by Bal Gangadhar Tilak in his book “The Orion” ,1893 and Pt. Raghunandan sharma in his book “वैदिक समप्ती”,subodh pocket books, ISBN-10 8187961171, respectively.
• 5. Pandey ,Ram Chandra, suryasiddhanta ISBN-10 : 9381484651,Chowkhamba Publications.
• 6. K.M Munshi ,Foreword, ”The history and culture of the Indian people, Vol.5,viii.