NASA announced Wednesday that cost overruns and delays have forced it to cancel a planned moon rover it already spent $450 million to develop, marking a significant setback for the agency’s lunar exploration program. NASA announced Wednesday that cost overruns and delays have forced it to cancel a planned moon rover it already spent $450 million to develop, marking a significant setback for the agency’s lunar exploration program. Space Exploration Phys.org – latest science and technology news stories