Space travel: For safety and environmental protection, small satellite monitors the oceans with AIS and camera
The small satellite OTTER (Optical Traffic Tracking Experiment for Responsive Space) orbits the earth at an altitude of 500 kilometres and is expected to remain in operation for around two years. The German Aerospace Centre (DLR) is carrying out the mission together with industrial partners. The experimental satellite belongs to the class of nanosatellites and is a so-called 3-unit CubeSat - about the size of a shoebox.
AIS reception from orbit helps in the fight against the shadow fleet
OTTER records the position signals from the Automatic Identification System (AIS) of ships. An additional camera on board photographs the corresponding sea areas in order to verify the AIS data. Both sources of information are combined and transmitted to the ground station, where they are analysed.
The data collected will be used to monitor maritime activities such as illegal fishing, ships in distress, oil spills and the manipulation of AIS signals. The latter is a growing problem, as ships can deliberately falsify or switch off their position data. The combination of AIS reception and optical verification is intended to detect such discrepancies.
Small satellites as a supplement to large systems
The use of space-based infrastructure offers a major advantage over land- and sea-based systems: satellites create situational images regardless of national borders. Small satellites are intended to supplement the existing capabilities of existing surveillance systems. Several smaller, easily replaceable satellites have a higher resilience and greater coverage.
OTTER is part of DLR's Responsive Space research. Responsive space means that space-based services can be provided quickly - important for replacing failed satellites or closing gaps in the infrastructure. The Responsive Space Cluster Competence Centre (RSC³) in Trauen is responsible for the OTTER mission and has clean rooms and test facilities for small satellites.
The satellite was launched on a SpaceX rocket in the USA. After around two years of operation, OTTER will use an electric propulsion system to enter the Earth's atmosphere at an accelerated rate and burn up. The mission is designed as an experiment and is intended to show where there is still a need for research and how well small satellites can support large existing maritime reconnaissance systems.
Technical data:
- Satellite type: 3 Unit CubeSat (nanosatellite)
- Weight: 6 kg
- Size: shoe box size (approx. 10 x 10 x 30 cm)
- Orbit: 500 km altitude (low earth orbit)
- Mission duration: approx. 2 years
- Instruments: AIS antenna, camera, receiver, reflectors
- Drive: Electric drive for controlled re-entry
- Launch: 28 November 2025, SpaceX rocket, USA
- Operator: DLR, Responsive Space Cluster Competence Centre (RSC³) Trauen
Other maritime earth observation systems:
