Five Civilisations —
Expanded comparative deep-dive

1) Babylonian astronomy

Strength: long-duration records. Clay tablet archives transformed astronomy into predictive computation. Planetary periods and eclipse cycles were tracked in a proto-scientific data tradition.

2) Egyptian astronomy

Strength: architectural precision and civil-calendar integration. Star risings (especially Sirius) aligned with Nile behavior and seasonal administration.

3) Greek astronomy

Strength: geometric and mathematical modeling. Greek astronomers formalized coordinate systems, angles, and precession calculations in analytical form.

4) Mayan astronomy

Strength: cyclic calendar engineering. The Long Count and ritual calendars linked planetary cycles, ritual timing, and historical memory across large periods.

5) Tamil astronomy

Strength: living continuity. Sidereal framework, Nakshatra usage, Panchangam practice, and temple-culture integration preserved astronomical awareness in daily life.

Civilisation	Primary method	Time architecture	Legacy pattern
Babylonian	Tabulated observation	Planetary/eclipses	Data-driven prediction
Egyptian	Monument alignment	Civil + stellar cycles	Sky-ground architecture
Greek	Mathematical formalism	Geometric models	Theory tradition
Mayan	Interlocking calendars	Long-count cycles	Cyclic cosmology
Tamil	Sidereal ritual calendar	Nakshatra + Panchangam	Living applied astronomy