The corpus, every claim citable.

Aryabhatiya I.6 (Dasagitika, 499 CE) gives Earth's axial tilt (the obliquity of the ecliptic) as 24°. Modern measurement is 23.44°. The 0.56° discrepancy isn't a measurement error: Earth's obliquity oscillates between ~22.1° and ~24.5° on a 41,000-year cycle (Milankovitch orbital forcing), and was ~24° several thousand years before Aryabhata wrote — consistent with his value reflecting inherited observational tradition from earlier Indian astronomy.

The Aryabhatiya of Aryabhata · tr. W. E. Clark, 1930