Schema: CREATE TABLE table_name_66 (apparent_magnitude INTEGER, ngc_number VARCHAR, object_type VARCHAR, constellation VARCHAR)
Question: what is the lowest apparent magnitude when the object type is spiral galaxy, the constellation is leo minor and the ngc number is more than 3021?
SQL: SELECT MIN(apparent_magnitude) FROM table_name_66 WHERE object_type = "spiral galaxy" AND constellation = "leo minor" AND ngc_number > 3021