The first interplanetary explorers may not go alone, but they will certainly be venturing way beyond the reach of our human tribe.
원문출처 : http://edition.cnn.com/2015/02/11/opinion/opinion-space-isolation-challenge/index.html?eref=edition
원문출처 : http://edition.cnn.com/2015/02/11/opinion/opinion-space-isolation-challenge/index.html?eref=edition