Background

Before communications satellites, long distance wireless communication relied on radio waves reflected off a layer in the upper atmosphere called the ionosphere. Such communication was not very reliable, however, especially in the Canadian North. To help resolve this, scientists needed to better understand the ionosphere. When the Soviets launched the Sputnik satellite in 1957, scientists saw the potential to study the ionosphere from above. Sputnik also prompted the development of Canadian expertise in space technology.

Concept & Engineering

When the Americans invited proposals for satellite-borne experiments, the Defence Research Telecommunications Establishment (DRTE) in Ottawa submitted an ambitious plan to "sound" the ionosphere from the top. The National Aeronautics and Space Administration (NASA) agreed to launch the experiment on a NASA satellite. Engineers soon realized that the sounder system could not be designed independently of the satellite, so DRTE undertook to supply its own satellite to carry the experiment.

The satellite was largely designed, built and tested by DRTE, the forerunner of the Communications Research Centre Canada, on this site. Innovative design using transistors, solar cells, long extendible antennas and long-life batteries, and exceptionally rigorous testing proved fundamental to Alouette's success. The role of Canadian industry, the National Research Council, NASA and other Defence Research Board establishments was also vital to the success of the programme.

The Science

From its orbit 1000 km above Earth, Alouette probed the ionosphere below. For 10 years it sent data to ground stations where it was stored on magnetic tapes for analysis. Scientists studied the regular patterns in the ionosphere caused by the sun's radiation and found many new features related to the Earth's magnetic field. The data confirmed that in the North, the ionosphere is too unsettled to predict.

The Legacy

In the wake of Alouette's success, the government moved to support space communications and the growth of a Canadian space industry. This led to Canada becoming the first country to have its own geostationary communications satellite system (Anik satellites), followed by earth observation satellites (RADARSAT), satellite-aided search and rescue (SARSAT), and space robotics (Canadarm) supplied to NASA space shuttles and the International Space Station.