An academic paper in the Indian Journal of History of Science presents a detailed analysis of a recently recovered 6th-century manuscript from the Kashmiri school of astronomy. The text, attributed to the astronomer Lalla, details trigonometric corrections for lunar parallax that exceed the accuracy of contemporary models used in the Mediterranean and the Middle East.
The study highlights how Lalla used early sine tables to calculate the apparent shift of the moon's position when viewed from different points on Earth. This level of mathematical sophistication confirms that ancient Indian astronomers had a deep theoretical understanding of the Earth's sphericity and the significant distance between the Earth and its satellite, long before the telescopic era.