Alouette-1 was a small ionospheric space based observatory instrumented
with an ionospheric sounder (radio transmitter), a VLF radio wave receiver,
an energetic particle detector, and a cosmic radio ... noise experiment.
EXTERIOR EQUIPMENT: Extended from the satellite skin (shell) were two
dipole antennas (45.7-meter and 22.8-meter long, respectively) which were
shared by three of the experiments on this spacecraft.
SPACECRAFT ROTATION (SPIN): The satellite was spin-stabilized at
about 1.4 rpm after antenna extension. After about 500 days in orbit,
the ALOUETTE-1 spin rate slowed more than had been expected, to about
0.6 rpm when satellite spin-stabilization failed. It is now believed
that the satellite gradually progressed towards a gravity gradient
stabilization with the longer antenna pointing earthward. Attitude
information was deduced from a single onboard magnetometer only, and
aided by temperature measurements on the upper and lower heat shields.
DATA ACQUISITION: Alouette-1 was an early space era satellite, and
there was no onboard tape recorder so data were available to the
ground stations only from the immediate vicinity of the telemetry
stations. The ground telemetry stations were located to provide
primary data coverage near the 80 degrees West meridian and in
areas near Hawaii, Singapore, Australia, Europe and Central Africa.
Initially, data were recorded for about 6 hours per day. In September
1972, spacecraft operations were terminated.