A famous claim: a 14th-century commentary on the Ṛgveda encodes light's speed at ~186,000 miles per second.
Sāyaṇa's commentary on Ṛgveda 1.50: a phrase taken to mean light/the sun travels '2,202 yojanas in half a nimeṣa.'
— Sāyaṇa's bhāṣya on Ṛgveda 1.50.4 (14th c. CE)
The speed of light ≈ 186,282 miles/second (299,792 km/s).
A popular claim that doesn't hold up — here's the honest story.
This is the single most-forwarded 'the Vedas knew science' claim, so it's worth getting right. Sāyaṇa, a 14th-century commentator, glosses a hymn to the sun with a line about something covering 2,202 yojanas in half a nimeṣa. Pick particular values for the yojana (a distance unit that ranged widely) and the nimeṣa (a tiny time unit), and the arithmetic can be made to land near the speed of light.
Why it doesn't hold up: the result depends entirely on cherry-picking which yojana and nimeṣa you use — other perfectly valid values give answers off by large factors. The verse is in praise of the *sun*, and the natural reading is about the sun's apparent motion, not the speed of light, a concept Sāyaṇa had no framework for. The 'match' is retrofitted. We include this card precisely because you *will* hear the claim — and now you'll know the real story, which is more interesting than the myth: a window into how easily numbers can be made to say what we want.