The head of China’s space agency will visit NASA Administrator Sean O’Keefe next week, a move one U.S. expert said could mean increased cooperation between the two countries. The December 2 meeting with Chinese National Space Agency Administrator Laiyan Sun had been under discussion for months, O’Keefe said on Tuesday. He stressed international cooperation was part of President George W. Bush’s vision for space exploration, which includes human missions to the moon and eventually to Mars.