When the space exploration initiative was announced, Congress asked the NRC to reviewthe science NASA proposed to carryout under the initiative. It also asked the NRC toassess whether this program would provide balanced scientific research across theestablished disciplines supported by NASA in addition to supporting the new initiative. In 2005, the NRC released three studies focusing on a portion of that task, but changes at NASA forced the postponement of the last phase. This report presents that last phasewith an assessment of the health of the NASA scientific disciplines under the budgetrequests imposed by the exploration initiative. The report also provides an analysis ofwhether the science budget appropriately reflects cross-disciplinary scientific priorities.