Why did Tycho Brahe invite Johannes Kepler to Prague?

Tycho Brahe invited Johannes Kepler to his court near Prague in 1600 to assist him in his ambitious project of reforming the foundations of practical astronomy.1

Tycho had set himself the task of amassing a completely new, highly precise set of planetary observations to correct existing records. By bringing Kepler into his circle, Tycho sought to utilize Kepler's mathematical expertise to help analyze this data. This collaboration proved pivotal; following Tycho's death in 1601, Kepler inherited these extensive and accurate observational records. Access to this critical resource allowed Kepler to move beyond ancient theoretical models and eventually discover his laws of planetary motion, including the realization that Mars moves in an elliptical orbit.1