{"knowledge_schema": {"broad_category": "Astronomy \u2192 Stellar Composition \u2192 Metallicity", "refinement": "This problem involves calculating the relative abundance of iron in the photospheres of two stars based on their metallicities compared to the solar composition.", "specific_scope": "The focus is on determining the ratio of iron atoms in the photospheres of Star_A and Star_B using their given metallicities and the solar iron abundance.", "goal": "Calculate the ratio of iron atoms in the photospheres of Star_A and Star_B based on their metallicities."}, "summary": "This problem is centered on the concept of metallicity in stars, which indicates the abundance of elements heavier than helium, particularly iron. Given the metallicities of two stars, Star_A and Star_B, we can calculate the ratio of iron atoms in their photospheres relative to the solar composition. By using the provided metallicity values and the solar iron abundance, we can derive the ratio of iron atoms, leading to the conclusion that the answer is 10^0.3."}