New Microsatellite Boosts Norwegian Maritime Monitoring
Canada’s Space Flight Laboratory (SFL) has launched Norway’s NorSat-4 maritime monitoring microsatellite.
The seventh spacecraft developed for the Norwegian Space Agency (NOSA) by SFL, NorSat-4 carries a fifth-generation Automatic Identification System (AIS) ship tracking receiver and a first-of-its-kind low-light imaging camera.
Built on SFL’s 35-kg DEFIANT microsatellite bus, NorSat-4 launched from Vandenberg Space Force Base in California aboard the SpaceX Transporter-12 rideshare mission on January 14.
The low-light optical camera expands the Norwegian Coastal Administration’s ability to detect and track vessels in its Arctic territorial waters by supplementing the AIS receiver aboard the satellite.
Safran Reosc of France built the camera under contract with the Norwegian Defence Research Establishment to optically detect vessels longer than 30 meters in Arctic darkness.
The camera is a demanding payload because it requires active thermal control to maintain low-light image quality and also needs extremely precise attitude control for accurate image geolocation. Additionally, SFL designed and manufactured a very compact mechanical iris shutter for the camera aperture, protecting the device from direct sun exposure in orbit.
SFL has a long history of supporting Norway’s leadership in space-based maritime traffic monitoring beginning with the 7-kg AISSat-1 nanosatellite in 2010. This mission proved that AIS signals could be detected from space. The AISSat-2 nanosatellite followed in 2014. AISSat-1 and -2 far exceeded their design expectations, operating for 12 and nine years, respectively.
Norway expanded its small satellite program to include a series of larger satellites named “NorSat” to accommodate larger instruments and more elaborate missions, launching NorSat-1 and -2 in 2017 and NorSat-3 in 2021. Each carried successively improved AIS receivers developed by Kongsberg Seatex along with experimental payloads. Among the most important technological successes achieved during this period was a foldable high-gain VHF Yagi antenna, designed and built by SFL, that could be deployed in orbit after launch.
Another standout mission for NOSA and SFL has been the NorSat-TD (Technology Demonsration) microsatellite launched in April 2023. In addition to its primary mission of AIS ship tracking, NorSat-TD carries multiple experimental payloads including a laser communications device called SmallCAT. This Dutch-built instrument was among the first ever to transfer data from a microsatellite to a ground station by optical link. This accomplishment was made possible by precise attitude control and fine steering technology developed and refined by SFL for low-mass spacecraft.
