From 1889 through 1927, the Harvard College Observatory (HCO) operated a southern sky photography station in the Peruvian Andes. This exhibit uses their photography, journals, and scientific products to illustrate their expedition as a moment of informal empire in the creation of our scientific modernity. Here, methods of extraction and exploitation elevated North American scientific prestige at the cost of Peruvian national development. Under labor regimes of race and gender, and with land-grabs, water policy, and walls, this imperialism created our modern cosmos.