Place  /  Explainer

Astronomy On The Flats

How the moons of Mars and the death of a president altered the late nineteenth-century Washington, DC, landscape.

Simon Newcomb often arose from his bed in the middle of the night to walk two miles to the Naval Observatory grounds. In the 1860s, the young astronomer lived east of 13th Street NW and north of the White House.[1] His walk cut west, just north of the elegant homes on Lafayette Square, and through Washington Circle before arriving at the Observatory. While the large, domed building sat secluded on the banks of the Potomac harbor, its environment left much to be desired. One of the city’s main sewers fed into the marshlands of the Potomac flats, where malaria and the stench of the river hung in the air. River fog shrouded the Observatory during certain months, preventing observation, and the growing city after the Civil War only added insult to injury. Observatory workers feared the miasmas—a belief in the danger of unsanitary air and smells—of the flats and the environment’s threats to their scientific work. They considered sleeping on or near the Observatory grounds hazardous, so most of them lived a mile or more away. But if the clouds cleared out after a hazy evening, Newcomb would take a few hours of sleep at home and then return to the Observatory to continue his work.

During the 1860s, wartime construction populated the Observatory’s undeveloped neighborhood. Walking from his home east of the Observatory, Newcomb passed the storehouses of the Quartermaster and Subsistence Departments, which occupied the southwestern part of the city. A heavy rain transformed these streets into canals. The mud, worn down by iron wheels, created swamps that thickened with the sun’s heat, returning to liquid with the next summer storm. At night, as Newcomb eagerly marched his way back to the Observatory grounds, rats, engorged on an ample storehouse food supply, competed for the right of way in the mud-filled streets.[2]

The astronomers and aides had proposed relocating the Naval Observatory for decades before relocation finally happened in 1893, and the District’s Board of Health had advocated for the reclamation of the Potomac flats in the early 1870s.[3] But it was not until 1877, after Naval Observatory astronomer Asaph Hall discovered the moons of Mars, that debate truly ensued over the location of the Observatory, the health of the environment, and the sad state of the southwestern part of the city. The tale of the Naval Observatory in late nineteenth-century Washington reveals the interconnectedness of science, city, and environment. In our story, this relationship blends the built environment with the natural environment, city planning, and disease geographies. Simply put, science and city development became interlocking parts in a larger story about urban modernity in the nascent capital city.[4]