{"knowledge_schema": {"broad_category": "Astronomy \u2192 Stellar Properties \u2192 Luminosity", "refinement": "This problem involves understanding the relationship between the physical properties of stars (radius and mass) and their luminosity, particularly in the context of black body radiation.", "specific_scope": "The focus is on comparing the luminosities of two stars with known ratios of radius and mass, while also considering their spectral characteristics and radial velocities.", "goal": "Calculate the factor by which the luminosity of Star_1 exceeds that of Star_2 based on their physical properties."}, "summary": "This problem examines the luminosity of two stars with different radii and masses, specifically Star_1 being 1.5 times larger in both aspects than Star_2. By applying the Stefan-Boltzmann law, which relates a star's luminosity to its radius and temperature, we can determine how much greater Star_1's luminosity is compared to Star_2. The goal is to compute this factor of luminosity difference, given the stars' characteristics."}