Placing Canada on the Celestial Map
In the 1950's at the height of the Cold War, DRB laboratories were involved in research and development to keep Canadians abreast of leading edge technology and ensure that Canadian forces were adequately equipped for their defence role.
Research at the DRTE was directed at improving communications via various radio bands. In that era, prior to communications satellites, High Frequency (HF) or short wave radio was the main mode of communication, particularly over long distances. However, HF radio depends on reflections from the ionosphere, a layer of ionized gas high above the Earth. The ionosphere tends to be irregular, particularly at northern latitudes, and often causes severe difficulties in maintaining radio contact. At DRTE, studies to improve such radio communications were a prime area of research. Although both theoretical and field studies were carried out, such studies were limited by the scarcity of ionospheric data, available from only a few sites and from the lower layers of the ionosphere. Scientists had long dreamed of using a satellite to study the ionosphere from above. The Americans and the Soviet Union had both announced plans to launch artificial satellites as part of the International Geophysical Year program in 1957-1958. The Space Age began with the launch of Sputnik 1 on October 4, 1957. The first American satellite, Explorer 1, followed on January 31, 1958. The Americans then solicited proposals for involvement of scientists from other countries in joint programs. Canada was quick to respond.
Ground-based techniques used to study the ionosphere are similar to radar. Radio pulses were transmitted from the ground and reflected back to the ground by the ionized layers. The elapsed time was used to calculate the height of the layers and the frequencies reflected gave a measure of the density of electrons. The equipment used to make these measurements was known as an ionosonde and the data were presented in a format called an ionogram. Analysis of ionograms from a network of ionosondes was used both empirically to predict the frequencies for use on specific circuits, and to test theoretical models of the ionosphere.
The Canadian proposal was to integrate an ionosonde into a satellite. Several advantages were anticipated. For the first time, the "topside" of the ionosphere could be observed giving much more information about the layers. A sequence of ionograms recorded as the satellite orbited the Earth would show spatial variations. Observations could be made over inaccessible terrain such as Northern Canada. Six counters for energetic particles were to be included, as it was felt that a knowledge of energetic particle fluxes would be essential to an understanding of the ionosphere, particularly in auroral regions. This experiment was to be provided by the National Research Council. A simple audio-frequency receiver with AGC (automatic gain control) was to be coupled to the sounding antenna. The receiver was intended to measure audio-frequency atmospherics, whistlers, and VLF emissions, particularly in the auroral zone where VLF emissions appear to be related to ionospheric storm effects.
The objectives were
- To bring Canada into the Space Age by developing a space capability.
- To contribute to space engineering and technology.
- To improve the capability to use High Frequency communications by studying the ionosphere from above.
To measure the electron density distribution in the ionosphere at altitudes between 300 and 1000 kilometres.
- To study for a period of a year, the variations of electron density distribution with time of day and with latitude under varying magnetic and auroral conditions, with particular emphasis on high latitude effects.
- To determine electron densities in the vicinity of the satellite by means of galactic noise measurement, and to make observations of related physical phenomena, such as the flux of energetic particles.
The proposal was submitted in 1958 and accepted by NASA on April 20, 1959. While several people had input to the original concept, the proposal was submitted to NASA by Dr. John Chapman and Dr. Eldon Warren. Chapman became the Program Manager. Keith Brown headed the engineering team. Dr. Colin Franklin was responsible for the electrical systems and John Mar for the mechanical design. Eldon Warren led the group of scientists. On the 25th anniversary of the Alouette launch, a list was compiled of more than 100 people who worked on Alouette for at least a year.
The spacecraft was largely designed and integrated by the DRTE team. It was very sophisticated for its time, making use of transistors and solar cells, a new space age technology for generating electricity. One group of DRTE engineers was familiar with transistors from their experience in developing a Doppler radar navigation set for aircraft. Some elements were provided by Canadian industry. De Havilland built the satellite structure, and their Special Products and Applied Research Division (SPAR) developed the long antennas known as STEMs (Storable Tubular Extendable Member). RCA of Montreal was called upon to design a special transmitter to transfer large quantities of data from the satellite to Earth stations.
Other DRB laboratories were also involved. Specialists at the Defence Chemical, Biological and Radiation Laboratory (DCBRL) ensured the reliability of the batteries. Facilities for environmental testing were installed at the Canadian Armament and Research Development Laboratory (CARDE) at Valcartier, Québec.
The sounding antennas (STEMs), which protrude from the satellite, were a unique feature of Alouette. Based on an invention of NRC engineer George Klein, they were the first product of the de Havilland division that became SPAR Aerospace Inc. Made of heat annealed spring steel, four inches wide, and wound flat on spools during satellite launch, they formed closed tubes one inch in diameter when extended. After the satellite was injected into orbit, the antennas were extended by an electric motor driving rubber friction-bands, to form two rigid crossed dipoles 150 feet and 75 feet from tip-to-tip. A NASA team under John Jackson worked with their Canadian counterparts. NASA provided final environmental testing and the launch vehicle and facilities. Alouette 1 was launched on September 29, 1962 from Vandenberg Air Force Base, California, aboard a Thor Agena B rocket.
With Alouette, Canada became a space faring nation, the third country after the USSR and USA to have built a successful satellite. Alouette was the cornerstone on which Canada became a leader in the peaceful uses of space and on which a competitive space industry has been built. Designed for a one year lifetime, the spacecraft exceeded all expectations and was decommissioned on its tenth anniversary. Canadian engineers acquired expertise in space technology and became known for the reliability of their products. It was one of the most successful scientific satellites ever and ushered in a new era of scientific co-operation. More than one million ionograms were produced. Canadian scientists gained prominence as world experts on the upper atmosphere. In 1987, Alouette was designated one of the ten most outstanding achievements in the first 100 years of engineering in Canada. In May 1993, the global significance of the project was recognized when it was designated as an International Milestone of Electrical Engineering by the Institute of Electrical and Electronic Engineers (IEEE), the largest technical organization in the world.
In accepting the IEEE Milestone Award, which honours significant world achievements in electrical, computer and electronic engineering, Admiral J.R. Anderson, Chief of the Defence Staff commented, "I can't help but marvel at the brash confidence, - the boldness - of the group at DRTE who decided to take on the world and build one of the most complex satellites of its day, and to do the job so well that it set world records for scientific discoveries, for length of deployed antennas, for battery life and for longevity in space." At a time when most satellites had a useful life span of a few months, Alouette functioned for ten years, before it was turned off from the ground. At the ceremony, Colin Franklin, one of the original members of the Alouette program noted, "NASA later admitted publicly that they and the CRPL (Central Radio and Propagation Laboratory in the US) were so convinced that Alouette could not possibly function for more than an hour or two, if at all, that they had made no plans to use data from it."
A plaque commemorating the engineering milestone is on display at the Shirleys Bay research site. The plaque also commemorates the more than one hundred people who worked on the Alouette program.
Alouette 1 was followed by the ISIS program in which the space technology was transferred to Canadian industry and three more Canadian scientific satellites were built.
The prototype of Alouette 1 and many related artifacts are preserved in the permanent collection of the . Many of the pieces are on display in the permanent space exhibit at the Museum. Considerable documentation and photos are associated with the collection. Information on the photos used in the exhibit is available in the Resource Centre of the Museum.
Dr. John Chapman's papers are held in the National Archives of Canada.
Hartz, Theodore, R., and I. Paghis. Spacebound. Ottawa: Minister of Supply and Services, 1982.
Jelly, Doris, H. Canada: 25 Years in Space. Polyscience Publications and National Museum of Science and Technology. Montreal, 1988.
Doris Jelly, Friends of CRC.
created on June 25, 1996 by Cynthia
Last updated on February 5, 2001 by Stu McCormick
Copyright © Friends of CRC, 1997