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 have always calculated accurately the motion of planets, sunset, sunrise, eclipses, etc. without using telescopes or any other machinery.
It is to be noted that Bhatta Bhaskara (probably from the 10th century) made the same statement in his commentary on Taittiriya Brahmana, another Hindu Veda. He says this to be an old tradition.
The fourth verse of the Rigvedic hymn 1:50 (50th hymn in book 1 of rigveda) is as follows:
तरणिर्विश्वदर्शतो जयोतिष्क्र्दसि सूर्य |
विश्वमा भासिरोचनम |
taranirviśvadarśato jyotishkridasi sūrya | viśvamā bhāsirocanam ||
This means “Swift and all beautiful art thou, O Surya (Sun), maker of the light, illuminating all the radiant realm.”
Exlpaining this verse in his Rig Veda commentary, Sayana, who was a minister in the court of Bukka of the great Vijayanagar Empire of Karnataka in South India (in early 14th century), says:
tatha ca smaryate yojananam. sahasre dve dve sate dve ca yojane
ekena nimishardhena kramaman.
This means “It is remembered here that Sun (light) traverses 2,202 yojanas in half a nimisha.”
Note: Nimisharda = half of a nimisha
In the vedas Yojana is a unit of distance and Nimisha is a unit of time.
Unit of Vedic Time: Nimisha
The Moksha Dharma Parva of Shanti Parva in Mahabharata describes Nimisha as follows:
15 Nimisha = 1 Kastha
30 Kashta = 1 Kala
30.3 Kala = 1 Muhurta
30 Muhurtas = 1 Diva-Ratri (Day-Night)
We know Day-Night is 24 hours
So we get 24 hours = 30 x 30.3 x 30 x 15 nimisha
in other words 409050 nimisha
We know 1 hour = 60 x 60 = 3600 seconds
So 24 hours = 24 x 3600 seconds = 409,050 nimisha
409,050 nimisha = 86,400 seconds
1 nimisha = 0.2112 seconds (This is a recursive decimal. The wink of an eye is equal to 0.2112 seconds.)
1/2 nimisha = 0.1056 seconds
Unit of Vedic Distance: Yojana
Yojana is defined in Chapter 6 of Book 1 of the ancient vedic text “Vishnu Purana” as follows:
10 ParamAnus = 1 Parasúkshma
10 Parasúkshmas = 1 Trasarenu
10 Trasarenus = 1 Mahírajas (particle of dust)
10 Mahírajas= 1 Bálágra (hair’s point)
10 Bálágra = 1 Likhsha
10 Likhsha= 1 Yuka
10 Yukas = 1 Yavodara (heart of barley)
10 Yavodaras = 1 Yava (barley grain of middle size)
10 Yava = 1 Angula (1.89 cm or approx 3/4 inch)
6 fingers = 1 Pada (the breadth of it)
2 Padas = 1 Vitasti (span)
2 Vitasti = 1 Hasta (cubit)
4 Hastas = a Dhanu, a Danda, or pauruSa (a man’s height), or 2 Nárikás = 6 feet
2,000 Dhanus = 1 Gavyuti (distance to which a cow’s call or lowing can be heard) = 12,000 feet
4 Gavyutis = 1 Yojana = 9.09 miles
Calculation of the Speed of Light from the Rig Veda:
So now we can calculate what is the value of the speed of light in modern units based on the value given as 2202 yojanas in 1/2 nimisha
= 2,202 x 9.09 miles per 0.1056 seconds
= 20,016.18 miles per 0.1056 seconds
= 189,547 miles per second
As per the Rig Veda the speed of light is 189,547 miles per second.
As per modern science the speed of light is 186,000 miles per second!