Ionosphere images from Alouette satellites
Designed and assembled in Canada, Alouette-1 was the first satellite built by a nation other than the United States or the Soviet Union. It was constructed at a time when most satellites had a useful lifespan of a few months. Although Alouette-1 was as complex as any previously launched satellite, rapidly advancing technology and the extreme care exercised in all phases of the Alouette-1 development had led the Canadian builders to expect that their satellite would operate for at least 1 year. However, Alouette-1 operated for 10 years in its first 3 months of operation, Alouette-1 produced some of the most exciting data obtained during the entire 50-year history of ionospheric research, and it continued to provide valuable information until its tenth birthday. Alouette-1 is best known for its swept-frequency topside sounder experiment. The other experiments (VLF, cosmic noise, and energetic particle measurements) were, however, equally successful and they also remained operational for 10 years. The Alouette-1 mission resulted in over 300 publications in refereed scientific journals. About 80 percent of the Alouette-1 publications were based on the ionograms obtained from the topside sounder experiment. In its first 3 years of operation, Alouette-1 obtained over a million ionograms, each equivalent to a snapshot of the ionosphere from the Alouette-1 altitude of 1000 km down to an altitude of about 300 km. These ionograms have provided data at all geomagnetic latitudes and at geographic latitudes ranging from 80° N to 80° S. After 10 years, Alouette-1 had produced two million ionograms.
The great majority of these ionograms are still archived on 35 mm negative film rolls, a format which is not very convenient for research. As a special project, the Canadian Space Agency has recently started to digitize some of these films. Although this data dates back from the ‘60s, there is still a significant scientific interest in analyzing this data to better understand the ionosphere. The first sets of data already available will be enhanced in the near future.
- Publisher - Current Organization Name: Canadian Space Agency
- Licence: Open Government Licence - Canada