Alouette 1 is a deactivated Canadian satellite that studied the ionosphere. Launched in 1962, it was Canada's first satellite, and the first satellite constructed by a country other than the Soviet Union or the United States. Canada was the fourth country to operate a satellite, as the British Ariel 1, constructed in the United States by NASA, preceded Alouette 1 by five months. The name "Alouette" came from the French for "skylark" and the French-Canadian folk song of the same name.
A key device on Alouette were the radio antennas consisting of thin strips of beryllium copper bent into a slight U-shape and then rolled up into small disks in a fashion similar to a measuring tape. When triggered, the rotation of the satellite created enough centrifugal force to pull the disk away from the spacecraft body, and the shaping of the metal caused it to unwind into a long spiral. The result was a stiff circular cross-section antenna known as a "STEM", for "storable tubular extendible member".
Development
Alouette 1 was part of a joint Canada-U.S. scientific program. Its purpose was to investigate the properties of the top of the ionosphere, and the dependence of those properties on geographical location, season, and time of day. Alouette 1 was advanced for its time, and NASA initially doubted whether the available technology would be sufficient. Nevertheless, NASA was eager to collaborate with international partners. NASA was convinced to participate by the prospect of obtaining data on the ionosphere, and Canada had the additional objective of developing its own space research programme. The United Kingdom also aided the mission by providing support at two ground stations, in Singapore and at Winkfield.
Experiments
Alouette 1 carried four scientific experiments: Sweep-Frequency Sounder. This experiment measured the electron density distribution in the ionosphere by measuring the time delay between the emission and return of radio pulses. The sounder was able to emit pulses with frequencies between 1 and 12 megahertz, with a power of 100 W. Energetic particle detectors. An arrangement of Geiger counters and scintillators for detecting energetic particles. VLF Receiver. An experiment for measuring both artificial and natural VLF signals. It was sensitive to frequencies between 400 and 10,000 Hz. Cosmic Radio Noise. Two long radio antennas used for detecting radio noise from the Sun and the Galaxy.
The satellite did not have a tape recorder to store data. It was only possible to obtain data when the satellite was in range of a receiving station.
Duplicate construction
Two satellites were built for redundancy in case of a malfunction; if the first unit failed, the second could be launched with only a couple of months delay. It took 3½ years after Alouettes proposal to have it developed and built. The satellites S27-2 (prototype), S27-3 (which became the launched satellite), and S27-4 (which became the backup) were assembled by Defence Research Telecommunications Establishment (DRTE) Electronics Lab in Ottawa, Ontario. The mechanical frame and the deployable STEM antennas were made by Special Products and Applied Research Aerospace (SPAR Aerospace), a former division of de Havilland Canada (DHC) in North York, Ontario, in a building which many years later (until 2012) housed the Canadian Air and Space Museum. The batteries used for Alouette were developed by the Defence Chemical, Biological, and Radiation Laboratory (DCBRL), another branch of DRB, and were partially responsible for the long lifetime of the satellite. The "Storable Tubular Extendable Member" antennas used were the first of DHC's STEM antennas used in space, and at launch were the longest (150 feet tip to tip). Companies such as RCA Victor and Spar Aerospace Limited produced some of their first pieces of space equipment for the Alouette 1 project. Parts used for the construction of Alouette 1 can still be found in the Musée des ondes Emile Berliner in Montreal, Quebec where part of the satellite was worked on.
Satellite launch and mission progress
Alouette 1 was launched via Thor-Agena-B two-stage rocket by NASA from the Pacific Missile Range at Vandenberg Air Force Base, California, USA at 06:05 UTC on September 29, 1962, into orbit around Earth. The satellite was placed into an almost circular orbit with an altitude of to with an inclination of 80.5°. The launch made Canada the third nation, after the USSR and the United States, to design and construct its own satellite. Alouette was used to study the ionosphere, using over 700 different radio frequencies to investigate its properties from above.