3. Who is George Klein? And what is a STEM, anyway?

George Klein was a National Research Council engineer who solved an important engineering problem in the design of Alouette, Canada's first satellite. A design criterion for satellites is that they should be as small and light as possible. The heavier and larger a satellite is, the more difficult it is to tranport into space. A large, heavy satellite will require a larger rocket that will need more fuel for launch, and that will therefore be more expensive. The purpose of Alouette was to study the ionosphere (a charged layer of the atmosphere) by bouncing radio signals off it from above. This required many very long antennas. How could a small satellite have such long antennas?

[Alouette with STEM antennas extended]George Klein solved this problem by inventing STEM antennas. STEM stands for Storable Tubular Extendible Member. This new type of antenna would unroll when the satellite reached orbit. More importantly, it would remain rigid when it was deployed. Alouette used four STEM's: two 11 m antennas, and two huge 22.5 m antennas. These antennas could not have fit in the rocket's nose cone if they were extended, but they did when they were rolled up inside Alouette.

STEM's were the first products of Spar Aerospace Ltd., the Canadian company now famous for building the Canadarm. The new Canadian STEM technology was so successful that it was later used on all the early American manned space flights.

George Klein was the 1995 inductee to the Canadian Science and Engineering Hall of Fame.

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Last updated on: 8 August 1997.