Eileen Clancy

[First draft of opening lines of an introduction to a book (?) about Sekiko Yoshida and her analysis of the cosmic ray data from the first U.S. satellite Explorer. My first attempt to set the historical scene. I am looking for workshop comments on ideas, language, and metaphors to consider.]

To study cosmic rays, it was necessary for scientists to move their laboratory to the space immediately above Earth. From the twenty-first century, it is difficult to imagine the ideas held by scientists and the public in the 1950s about the Earth and space before the first artificial satellites were launched. What we see is very much dependent on where we are standing, on what we are looking for, and even what we think we are looking for. To learn about the new ways of seeing that satellites enabled, one has to first understand the many things they did not know. The true shape of the Earth. The distance between the continents. Their own exact location on a geocoordinate grid. Weather, forestation and drought patterns. The existence of bands of deadly high radiation just above the atmosphere. How to accurately track small objects in the atmosphere. The origin of invisible cosmic rays. How a continuous stream of the sun’s explosions of magnetic particles is tied to the Earth and affects our communications networks (telephone, television, radio, etc.).

The tools they would need to discover these things still had to be thought of, invented and brought into use. A system of global positioning satellites. Computers with enough memory to handle huge amounts of calculations and new programming languages to do the math. Methods to capture analog data from instruments and convert it into digital bytes to be processed. International telecommunications networks powerful enough to transmit large amounts of data in real time. Global satellite tracking networks. Capabilities of capturing, handling, and analyzing heretofore unknown quantities of data.

In some ways, this moment of venturing into space could be compared to the early Europeans’ navigation of the Atlantic Ocean. Before 1400, Europeans did not venture into the mysterious and deadly North Atlantic. Without adequate instruments, including accurate timekeeping mechanism, and without charts, navigators did not dare leave the sight of the coastline. Eventually, oceangoing navigators from Europe guessed their ways into the powerful current of the Atlantic without maps of the ocean floor, currents or the even knowledge of the destinations on land that they were seeking to reach. After countless mishaps, the first navigators who located the correct currents to an oceanic highway were quickly transported to what would become the Americas.

Similarly, as human beings placed the first scientific instruments into orbit around the Earth, they were able to immediately grasp hugely important facts/truths at the same time.

As Matt Bille and Erika Lishock’s book about the launch of the first satellites notes, “Every satellite of this period offered opportunities for knowledge to scientists not even connected with the particular spacecraft.” One of the best illustrations of this may be the moment that scientists tracking the audio beeps from the Soviet Sputnik made the mental leap to conceive what eventually became the GPS navigation system. The men then inferred distances on Earth from Sputnick by triangulation. The Doppler Effect indicates that a moving object emitting sound varies in frequency depending on whether it is approaching an observer’s location or moving away from it. (The same phenomena is commonly noticed in the apparent change in pitch heard in railroad whistles.) “Bill Guier and George Weiffenbach of Johns Hopkins APL realized they could use the Doppler Effect to track Sputnik’s orbit.” Their supervisor, Frank McClure surmised that they would be able reverse this to determine location on Earth from satellites. (Bille, Lishock 112-113). Very soon thereafter, these scientists’ work morphed into the earliest GPS-like system of navigation satellites.

Handling the data captured by satellites was a thorny problem that would not be satisfactorily resolved until several decades later as new miniaturize hardware, software and memory storage came online. The first Explorer satellite didn’t have an onboard recorder. To enable tracking of the satellite, and to transmit data about the cosmic ray experiment on board, it broadcast telemetry—radio signals indicating its speed and direction. Data from telemetry and Explorer’s cosmic ray experiment were transmitted over radio waves that were picked up in spurts as the satellite passed over receiving stations across the Earth. These down linked radio waves were transformed into sounds electronically and recorded onto analog reel-to-reel audiotapes. Later, the audiotapes were played and their data written was onto long strips of paper. Scientists and technicians then had to convert these miles of paper by physically measuring the lines on the paper with rules, graphing the data points by hand, and converting these points into groups of numbers to be analyzed.

Were these scientists’ attempts to handle this early satellite data the historical precursors to contemporary questions about how to manage the processing and interpretation of “Big Data?” Not really. But although this was not the first moment in the twentieth century when scientists had to reckon with larger amounts of data than they had capacity to manage and interpret, the process of data reduction and analysis for the Explorer 1 marks a historically significant turning point in the acquisition of new quantities of this particular type of cosmic ray data generated from a location that had never been before attempted. And, the interpretation of the data used a technique that, although it had been used in Japan, for at least a decade (check!!) was utterly novel in the West.