How did Tycho Brahe’s observations help Johannes Kepler discover the laws of planetary motion?

Tycho Brahe’s contribution to Johannes Kepler’s work was foundational, as Brahe provided the most accurate astronomical observations available before the invention of the telescope.12

After Brahe’s death in 1601, Kepler inherited his extensive collection of observational data. Kepler, who had joined Brahe in Prague to refine his own cosmological theories, found that existing models—including those of Nicolaus Copernicus—could not account for the precise positions of the planets, particularly [Mars].134

Kepler’s analysis of Brahe’s data revealed that his own initial attempts to model planetary motion using circular orbits were inconsistent with the observations by about 8 minutes of arc. Because he trusted the accuracy of Brahe’s measurements (which were precise to within 2 minutes of arc), Kepler was compelled to abandon the traditional assumption of uniform circular motion. This rigorous reliance on Brahe’s data led Kepler to discover that planets move in elliptical orbits with the Sun at one focus, and that they sweep out equal areas in equal times.4253