How Was Mars Mapped for Globes?

In Mesopotamian texts, Mars is referred to as the “star of judgement of the fate of the dead”.

The existence of Mars as a wandering object in the night sky was also recorded by the ancient Egyptian astronomers and, by 1534 BCE, they were familiar with the retrograde motion of the planet.

By the period of the Neo-Babylonian Empire, the Babylonian astronomers were making regular records of the positions of the planets and systematic observations of their behavior. For Mars, they knew that the planet made 37 synodic periods, or 42 circuits of the zodiac, every 79 years. They invented arithmetic methods for making minor corrections to the predicted positions of the planets.

In Ancient Greece, the planet was known as Πυρόεις. Commonly, the Greek name for the planet now referred to as Mars, was Ares. It was the Romans who named the planet Mars, for their god of war, often represented by the sword and shield of the planet’s namesake.

In the fourth century BCE, Aristotle noted that Mars disappeared behind the Moon during an occultation, indicating that the planet was farther away. Ptolemy, a Greek living in Alexandria, attempted to address the problem of the orbital motion of Mars. Ptolemy’s model and his collective work on astronomy was presented in the multi-volume collection later called the Almagest (from the Arabic for “greatest”), which became the authoritative treatise on Western astronomy for the next fourteen centuries. Literature from ancient China confirms that Mars was known by Chinese astronomers by no later than the fourth century BCE. In the East Asian cultures, Mars is traditionally referred to as the “fire star” (火星) based on the Wuxingsystem.

In 1609 Johannes Kepler published a 10-year study of Martian orbit, using the diurnal parallax of Mars, measured by Tycho Brahe, to make a preliminary calculation of the relative distance to the planet.

In 1610 the first use of a telescope for astronomical observation, including Mars, was performed by Italian astronomer Galileo Galilei. With the telescope the diurnal parallax of Mars was again measured in an effort to determine the Sun-Earth distance. This was first performed by Giovanni Domenico Cassini in 1672. The early parallax measurements were hampered by the quality of the instruments.

Before the space age, astronomers mapped Mars through ground-based telescopes. Figures like Richard Anthony Proctor collated sketches by observers such as William Rutter Dawes, while Giovanni Schiaparelli, Camille Flammarion, and Percival Lowell drew extensive surface features.

Percival Lowell’s maps famously interpreted linear surface patterns as artificial “canals,” which were hand-painted onto early physical globes.

Because astronomical telescopes in the northern hemisphere inverted the view, early Martian globes and maps frequently placed the south pole at the top.

This rather odd-looking globe pictured left – reveals some fascinating snippets in the history of popular science, not the least of which is the relatively unknown work of Danish amateur astronomer Emmy Ingeborg Brun (1872-1929). According to Christie’s who published this article when the globe went to auction, only twelve recorded examples of her finely painted globes exist, and there is precious little information about her or them online.

The Royal Museums Greenwich in London, which owns one of those twelve, offers this brief bio of Brun: “Mars enthusiast and amateur astronomer who made a small number of globes, many for presentation to particular individuals and institutions. Her inscriptions suggest that she viewed Mars as a potential socialist religious Utopia.”

Indeed it seems Brun was a Red Planet admirer, and she had also fallen under the spell of American businessman and pop sci prophet Percival Lowell (1855-1916). Building on the works of an Italian astronomer, Lowell became convinced that he had discovered an extensive canal system on Mars, which, in turn, proved (to him) the existence of an ancient Martian civilisation. Lowell spent many years at his observatory in Flagstaff, Arizona, drawing the wrong conclusions about what he was seeing through the telescope. He published three books on the subject: Mars (1895), Mars and its Canals (1906), and Mars as the Abode of Life (1908). Powell’s discredited cartography fueled mid-twentieth-century science fiction novels like Heinlein’s Red Planet and Bradbury’s Martian Chronicles.

NASA’s Mariner 4, 6, and 7 in the 1960s, followed by Mariner 9 (which achieved first global coverage in 1971) and the Viking Orbiters, replaced optical illusions with real photography.

Because spacecraft imagery was incomplete or black-and-white, cartographers like those guided by Gerard de Vaucouleurs used airbrushes and pencils to blend telescopic data with early probe photos to bridge gaps on globe gores.

Early post-Viking (1976 onwards) discoveries replaced the mistaken green, blue, or grey hues of older globes with the actual rusty-orange, ochre, and light-brown tones of iron-rich Martian clay.

Modern globes and digital models rely on data from missions like the Mars Global Surveyor (featuring the MOLA laser altimeter), Mars Express, and NASA’s Mars Reconnaissance Orbiter (HiRISE).

Because Mars is smaller than Earth and features massive volcanoes (like Olympus Mons) and canyons (like Valles Marineris), cartographers often slightly exaggerate vertical relief on physical table globes so the topography remains visible.

Discover more –

A great article by National Geographic : What Mars Maps Got Right (and Wrong) Through Time

First image pictured : Wood engraving from Camille Flammarion’s “L’atmosphère: météorologie populaire” in 1888. (Credit: Wikimedia Commons)

Globe of the planet Mars made by Emmy Brun (Credit : Christies)

 

Explore an interactive version of this map ^^ here via National Geographic.