Table schema:
CREATE TABLE table_name_61 (ngc_number INTEGER, object_type VARCHAR, right_ascension___j2000__ VARCHAR)

Question: Which NGC number has an Object type of open cluster, and a Right ascension (J2000) of 06h01m06s?
SQL: SELECT MAX(ngc_number) FROM table_name_61 WHERE object_type = "open cluster" AND right_ascension___j2000__ = "06h01m06s"