 The U.S. may miss out on getting a look at moon rocks from a side of the moon we almost never get to see. Senior Chinese space official Bian Zegang confirms the call's gone out for experts around the world to come and help examine the rocks from the far side of the moon, with one exception, the U.S. The problem, he says, is the 2011 Wolf Amendment, which prevents direct U.S.-Chinese bilateral cooperation, which in this case hampers such exchanges.