{"knowledge_schema": {"broad_category": "Astronomy \u2192 Stellar Properties \u2192 Effective Temperature", "refinement": "This problem involves understanding the relationship between a star's physical characteristics (radius and mass) and its effective temperature (Teff) under different conditions.", "specific_scope": "The focus is on calculating the effective temperature of a star when its surface is partially covered by dark spots, affecting its overall luminosity and temperature.", "goal": "Determine the new effective temperature of the star when 40% of its surface is covered by dark spots."}, "summary": "This problem relates to astronomy, specifically the study of stellar properties, where we analyze how a star's effective temperature changes based on its surface conditions. The scenario describes a star with specific characteristics and asks for the calculation of its effective temperature when a portion of its surface is obscured. The goal is to understand how the coverage of dark spots impacts the star's luminosity and temperature, leading to the conclusion that the effective temperature is 4.5 when accounting for these factors."}