I have been doing some research into Vedic Cosmology. I use the term ‘Vedic’ to refer not only to the four Vedas but also the supplementary literatures such as the Vedangas, Upanisads and Puranas. Primarily, I have been studying the cosmology of the Puranas, especially the Bhagavata Purana aka the Srimad Bhagavatam. The Puranas usually present cosmological dimensions in terms of a measurement called a yojana. The conversion to miles is often taken as approximately 8 miles to one yojana although history shows that some Indian astronomers defined their own yojana, different in length to others’ yojanas.
In a poor English translation of the Visnudharmottara Purana, one of the Upapuranas, I found the following:
>>Markandeya spoke: When the sun went down in the water and when the dust is visible in the dim-dazzelings of the faint light, the orange-coloured glossy lights are visible Such eight-“Trasarnud” make a “Likshika” measurement, and that is “Shasharpa” and such several make-“Gaurasarshapa” Such “Sarshapa” and eight finger marks make a “Ashtaka” measurement and such twelve finger marks measurement in a conical measurement – as we call it – and such two make a “Hand-Measurement” or “Hasta” Four type of such is spoken as “Dhanu” and such thousand “Dhanu” make a “Sahasrika” measurement and such two measurements are called – “Gavyuti” – and such four are called as “Yojanas.” <<VdP 1.4.1-4
This appears to be a calculation of a yojana in terms of trasarenus (particles of dust seen in the sunlight passing through a window). The Srimad Bhagavatam describes this trasarenu as a hexatom – the combination of six atoms (SB 3.11.5).
I plan to get hold of the Visnudharmottara in Sanskrit and work towards a better translation of this section.
