Nina Czegledy – On Spatial Perception: Mapping the Earth – Charting the Sky. – 2006

From time immemorial mankind has been fascinated with the luminous mysteries of the night sky. The quest for stars and charting the heavens dates back thousands of years; hence astronomy is believed to be one of the oldest sciences in the world. Cosmography and uranometry are closely related to our perception of space. While spatial perception and experience may vary from time to time and culture-to-culture, nevertheless certain aspects of spatial sensing remain consistent features of human existence. What are these features? Did historical mapping of space alter our perception? How much do we know about the relationship between spatial cognition and the “digital sky”? Only some of the answers might be available, nevertheless it is worthwhile to pursue these points. This paper is focused on historical and contemporary perception of space including celestial mapping. Numerous aspects of mapping space such as military endeavors, scientific investigations or the increasing number of locative media projects are outside the scope of the present discussion.

The earliest attempts to map the sky were probably made by the ancient Egyptians. Over time a wide range of instruments including celestial globes, telescopes and other sighting devices aided surveys by the human eye. Gradually, various systems were developed to chart the movements of celestial bodies and the hypothetical organization of the universe. Babylonian classifications, dating to 3rd century BC, influenced the modified editions of Greek, Roman, and Islamic astronomers throughout centuries, leading to the mathematically defined system used to this day. Aristotle’s and the Ptolemaic system, placing the earth at the centre of the world, had an especially strong effect on cosmology throughout centuries, right up to Newton’s radically different depiction (1687) of universal gravitation with space extending geometrically where all bodies are attracted to each other. Islamic scholars extrapolated the Ptolemaic system and by the 13th and 14th centuries the advanced Arabic and Persian astronomical texts have reached Europe and translated into Greek became integrated into scientific source material. (Lachieze 1998)

European astronomy, cartography and navigation reached a golden age in the 16th century (Lachieze 1998). The revolutionary heliocentric theories by Copernicus (1473-1543) and discoveries by explorers such as Christopher Columbus, Vasco da Gama and Ferdinand Magellan, inspired and influenced the science and art of cartography and as a result fundamentally changed the charts of heaven and earth. This was indeed a stimulating period for mapping the universe. The medieval notion of perspective has been mostly vertical, the discoverers of the « new world » brought horizontal dimensions into vertical space. At this time, the study and practice of cosmography required extensive knowledge in mathematics, astronomy, cartography, navigation and even architecture. While an informal network of cosmographers –exchanging and updating information and selling their maps at the world renowned Frankfurt Book Fair – existed throughout Europe, the notes containing source information of the times were dispatched through war and/or pestilence-ridden territories, frequently causing considerable delay or never reaching the addressee. Yet, in the 16th century the power of maps became increasingly evident. Historical sources have been revisited and with the integration of new information, many terrestrial and celestial maps have been reshaped and revised often serving as instruments of social and political control to suit political goals. As the maps reached only the limited affluent readership, the cosmographic awareness of the general populace (often confined to their locale), is hard to estimate The shape and size of countries, continents or celestial constellations depicted on the charts, were frequently changed not only by factual data received or observed, but also according to political or religious affiliation, revealing the subjectivity of map making. Cartographers were persecuted even imprisoned for displeasing authorities with charts or annotations deemed politically or religiously incorrect. The ongoing versioning provides evidence that cartographical interpretation and manipulation of data dates back a long time. Thus, publications from this period offer a fascinating mixture of facts, myths and popular knowledge (Crane 2002).

Scientific investigators and innovators in this golden age of cosmography included Gerardus Mercator, Willem Blaeu and especially Peter Apian (1495-1552). Apian, professor of mathematics at the University of Ingolstadt in Bavaria introduced new scientific concepts and provided astronomical information in his books (Apian). Cosmographia his first major work, based largely on the Ptolemaic system, published in 1524 contained an introduction to astronomy, navigation, cartography and presented diagrams that included the earth’s climatic zones, methods for calculating latitude and longitude and the application of trigonometry for measuring distances. The lavishly illustrated Astronomicum Caesareum (Astronomy of the Emperor) published in 1540 –apparently influenced by Albrecht Durer’s earlier planisphere- presented an even more ambitious project. The splendid volume was dedicated to Charles V, the Holy Roman Emperor who was rumored to study cosmography himself.

For many centuries the distinction between astronomers, astrologists, mathematicians and cartographers were often blurred. The celestial maps they produced served as important instruments of visualizing spatial information. On these maps the stars were often grouped into constellations, which were believed to represent, divinities, sacred animals and other objects of religious significance. This complimented the medieval view of the universe, separated into layers relating to matter and spiritual or religious beliefs.

« Maps have as much to tell us about the religious and cosmological beliefs and cultural attitudes of the people who made them as they do about geophysical reality. Perhaps most important of all, maps are construct of social and political power. »(Short). Indeed maps, especially celestial maps have always carried a symbolic (social and political) meaning beyond the craft of mapmaking. Maps, according to J.B. Harley, are the social constructions of the world (Harley). Over the centuries, cartographic symbiology has emerged as tool in an effort to depict the world as accurately as possible and to transmit information to the reader of the maps. Celestial maps and atlases served multiple purposes including education, religious instruction, navigation and astronomical calculations. The maps were frequently annotated with extensive explanatory texts. In addition to providing a narrative, these texts also served the purpose of reading and remembering history. Memory and memorized images – deeply ingrained and often subconscious- serve to identify, interpret and supplement our perception. Visual mental imagery and memory play a key role in human consciousness, including information processing, abstract reasoning, language comprehension and even the physical act of visualization (Kosslyn 1999). Is image information represented in a spatial format? How much is a person’s perception of the blue sky due to memories of early visual experiences? The intimate spaces we all inhabit include our sensory biosphere. Sensory and motor information construct together an internal representation how we perceive space. The nature of this representation and the neural mechanisms underlying it has become a topic of great interest in cognitive neuroscience (Colby 1998). Lately, it has been agreed that spatial sensing involves multisensorial perception. Accordingly, Gardner (1984, 1993) suggested a multifaceted model of spatial intelligence including « the ability to think in pictures and images, the ability to perceive, transform and recreate different aspects of the visual-spatial world ». The combination of visualization and orientation forms the accepted basis for spatial ability and the capacity for understanding and manipulating three-dimensional mental imagery (McCuistion 1990). Beyond our corporeal environment we also experience social spaces some of them politically charged. Whereas visual imagery is a common occurrence, the question of how ‘mental pictures’ conform to the theory of cognition remains essentially unresolved.

Recently, in addition to conventional notions of space, we consider electronically enhanced or collapsed spaces such as cyber space, intelligent space, embodied space, etc. While some of these considerations are closely connected to evolving technologies, other aspects of augmented space, such sacred spatial experiences or cosmic mapping, date back to a long and complex history. Cartography existed long before the written word, yet today it employs the most up to date imaging systems. The advent of computers and satellites has revolutionized map-making simultaneously contributing to a contemporary shift in our perceptions of space and spatial abilities. The development of increasingly sophisticated and often remotely operated sensors changed the spatial component of a wide variety of specialized technologies from space explorations to biosciences. Correspondingly the notions of « private » or « public » space as we have formerly known it, have altered. In the last decades – from the very beginnings of space exploration- unique online resources have been derived from images and data returned by a series space missions.

Back in the 16th century, noted cartographers, had to search for several years for obtaining cartographic resources. Today the online VizieR catalogue service enables researchers in a few seconds to access published astronomical data by various criteria (VizieR). In contrast to the exclusive pen and brush drawn parchments of the 16th century, stellar maps are produced via satellite technology included in the Hipparcos and Tycho Catalogues (Hypparcos & Tycho), published by ESA in 1997. Hipparcos presented the very first space mission (1989) for measuring the positions, distances, motions, brightness and colours of the stars thus supplying invaluable information concerning the size and age of the universe. On the Hipparcos website online resources are provided for professional and amateur astronomers alike. Cosmic X-rays contribute significantly to these all-sky photographic surveys such as the Digitized Sky (Cosmic X-rays).

The magnitude of online resources is overwhelming. The Strasbourg astronomical Data Center (CDS) is committed to the collection and distribution of worldwide data sources. CDS’s SIMBAD (Set of Measurements and Bibliography for Astronomical Data) the largest worldwide astronomical database first released in October 1996, contains at the time of writing, over 3 million astronomical objects (outside the solar system), identified by 5.2 million citations and cross referenced information items (SIMBAD). The acronyms used by CDS, such as VizieR or Aladin, pay tribute to classical Islamic astronomy and the tales of The Thousand and One Nights (Lachieze, 1998). Instant access to online data for the visualization of a “digital sky” is available at the Virtual Observatory by CDS. Simultaneously, the Astronomers Bazaar provides access to thousands of online astronomical catalogues, including the interactive Aladin Sky Atlas (Aladin), accessible on a home computer. Aladin also provides an image database and powerful bibliographic links. It is of interest to note that Gerardus Mercator’s cartographic projections from the 16th century, remained embedded in cartographic thinking and were used in the Space Oblique Mercator Projection for the first satellite map of the US and somewhat later to map Mars by Mariner 8 and 9 (Landsat Program).

How are we able to absorb all this information? Considering how people understand spatial concepts, do the digital models representing information support or impede the effective use of that information? The relationship between physical space and the digital world is not yet fully established and the process how the semantic meaning of online information is described by one person (or organization) and absorbed by another remains also unclear. Even as it is difficult to assess how our own sense of place or space altered in the digital age, the scientific theories, instruments and methodologies of celestial mapping evolving over the centuries undeniably, clarified our understanding of the cosmos. Yet modern science has also deprived the sky of the mystery and the spiritual dimensions, which formed a fundamental part of cosmological spatial cognition. Today the physical sky and the symbolic sky seem to be separated. Considering the novel technical approaches one might pause and reflect on the impact of the difference between perception by the naked eye (perhaps enhanced by some analog tools) and the restricting size of the computer monitor. Unquestionably, shared, publicly available data created a new phase of active involvement as well as virtual links between a networked community with often-positive social and political consequences. In conclusion, the question remains, how has this new knowledge and the constellations of affiliations altered our fundamental perception of the mysteries of the Universe?

© Leonardo/Olats & Nina Czegledy, November 2006 / republished 2023