Though no structure is evident in the ground plan of the layout of the menhirs but when the shadow pattern of the structures were simulated for the extreme point of sunrise for latitude of Byse, an interesting pattern emerged. The researchers also tested the clusters for alignments to the extreme points of moonrise and moonset. The arrangement of these menhirs seems to be such that pairs of these stones frame the rising/setting sun/moon on significant dates. Using computer simulations, the team found that the standing stones are aligned to the north, east, south and west directions and also match the two solstices and equinoxes. While the two solstices mark the longest and shortest days of the year, an equinox occurs when the sun is in the same plane as the earth’s equator. “The study establishes that India had a strong intellectual tradition of precise astronomical observation not copied from any other civilization.

This is the first instance of a monument with intentional solar and lunar alignments among Indian megaliths. Astronomical purpose has been suggested in the design of alignments at a couple of sites in north Karnataka, but the large number of boulders involved has made inferences inconclusive. Four other menhir sites near Byse, which are currently under investigation, also show similar patterns.
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Source: Menon, S. M., Vahia, M. N. and Rao, K., Stone Alignment with Solar and Other Sightlines in South India, Current Science, Vol. 102, No. 5 (10 March 2012) Pp. 683-684.