The first quantitative estimate of the speed of light is seen in Indian vedic scholar Sayana’s commentary on the Rig Veda. It says that sun light travels 2,202 yojanas in the time span of a nimisharda (half a nimisha). The yojana is an ancient unit of length. Arthasastra defines it as being equal to 8,000 dhanus, which is equivalent to 9.09 miles. A nimisha is an ancient unit of time that is equal to 16/75 seconds. Thus 2,202 yojanas in half a nimisha is equal to 189,547 miles per second after conversion. The modern estimate of the speed of light is 186,281.7 miles per second.

This velocity of Light was calculated by Maxwell in the 19th century, but its was actually determined accurately thousands of years before in the Rig Veda. It was further elaborated by Sayana in the 14th century AD in his commentaries on Rig Veda. Indian Almanacs…