The Map That Changed the World of Mars

What signs might a curious extraterrestrial, observing the Earth through a telescope, seek in order to prove the presence of intelligent inhabitants? From interplanetary distances, the human species reveals its presence through the geometric nature and orderly arrangement of our land architecture (Figure 1). It is understandable, then, how the late 19th century observations of an intricate network of intersecting straight lines on Mars could be interpreted as evidence of intelligent inhabitants on the red planet.

Figure 1: A view of ordered and geometric land architecture on the surface of Earth, viewed from space. We might identify these as centre-pivot irrigated crop circles; an extraterrestrial might identify them as signs of intelligent life. (NASA Earth Observatory, 2001)

The announcement of “canali” on Mars was made in 1877 by an Italian astronomer, Giovanni Schiaparelli, and it sent a wave of Mars-hysteria surging through Europe and America (Schiaparelli, 1896). In Italian, “canali” means “grooves” or “channels”; however, it was translated into English as “canals” – a word connoting the handiwork of a Martian civilization. This sensational news was embraced, prompting such works of science- and pulp- fiction such as “The War of the Worlds” by HG Wells and “A Princess of Mars” by Edgar Rice Burroughs, which were eagerly consumed by the general public.

When, in 1892, Schiaparelli’s failing eyesight forced him to retire as an astronomer, a wealthy American man named Percival Lowell stepped up to the plate to continue making observations of Mars and to further elucidate the details of the canals (Lane, 2006). Although never formally trained, Lowell had a lifelong love of the red planet, and by 1894 had begun mapping Mars in his own observatory in Flagstaff, Arizona, built solely for this purpose.

Lowell experienced immediate success. He confirmed Schiaparelli’s observations and proffered 116 additional waterways in less than a year – his detailed cartographic sketches of the Martian surface (Figure 2) propelled him to be considered a foremost authority on the subject (Payne, 1904). And the alien civilization responsible for the observed intricate canal system, he argued, was equally real (Lowell, 1906).

Figure 2: “Map of Mars” by Percival Lowell, 1897, depicting the intricate network of canals he observed from his observatory on Mars Hill in Flagstaff, Arizona. He believed the dark circles at the intersection of the lines to be oases, and the dark areas in the upper regions of the map to be seasonal swamps. (Lane, 2006)

While the Martians of HG Wells were “malevolent, cool and unsympathetic”, Lowell’s Martians were benign, and even experiencing a catastrophic planet-wide drought (Cosmos, 1980). He believed that Mars was undergoing planetary aridification, its water evaporating into space, to the despair of its inhabitants. He explained the canals as a desperate engineering measure to transport the scarce water resources from reservoirs at the poles to thirsty cities around the planet (Lowell, 1908).

Making astronomical observations in Lowell’s time was not easy work. Even at his observatory’s high vantage point on Mars Hill, the conditions were plagued with bad “seeing”, the astronomical term for an unsteady atmosphere (Price, 2000). Hand-drawn sketches were the most widely employed way to capture what was seen through the telescope during fleeting moments of clarity.

Today, we have examined Mars using imaging technology free of subjectivity. We now know that the only real water-related features on Mars are ancient riverbeds – but they are of geologic origin and have long since dried up (Cosmos, 1980). The intricate network of canals reported by Schiaparelli and Lowell simply does not exist. Swept up in the Mars-mania, they saw what they wanted to see. Though these events took place over a century ago, the lesson is timeless: “where we have strong emotions, we are liable to fool ourselves” (Cosmos, 1980). We need to keep our mind open and our preconceptions to a minimum if we are to efficiently discover the true wonders of Mars.



Cosmos, 1980. [Documentary] Blues for a Red Planet. USA. 26 Oct.

Lane, M., 2006. Mapping the Mars Canal Mania: Cartographic Projection and the Creation of a Popular Icon. Imago Mundi-the International Journal for The History of Cartography, 58, pp.198–211.

Lowell, P., 1906. Mars and Its Canals. New York: Macmillan Company.

Lowell, P., 1908. Mars as the Abode of Life. New York: Macmillan

Payne, W.W., 1904. The ‘Canals’ of Mars. Popular Astronomy, 12, pp.365–375.

Price, F.W., 2000. The Planet Observer’s Handbook. 2nd ed. Cambridge, United Kingdom: Cambridge University Press.

Schiaparelli, G.V., 1896. Osservazioni astronomiche e fisiche sull’asse di rotazione e sulla topografia del pianeta Marte. Osservazioni Astronimiche e Fisiche. Roma.