At first glance, the maritime and space environments seem far removed from each other. Yet they impose comparable constraints: extreme environments, complex maintenance, uncertain communications, limited energy resources and stringent reliability requirements. In both cases, systems must observe, determine their position and communicate with minimal human intervention.

This proximity opens the way to technology transfers in navigation, sensors, imaging, materials and energy production.

Turning scattered observations into continuous knowledge

Surveillance resources are multiplying: satellites, drones, ships, buoys, underwater sensors and coastal infrastructure. But the information obtained often remains intermittent, fragmented and difficult to cross-reference.

The real challenge is therefore to ensure continuity of monitoring. It must be possible to detect a phenomenon, characterise it, track its development and rapidly transmit actionable information. This approach is particularly relevant to maritime security, rescue at sea, combating illegal fishing, pollution monitoring, biodiversity protection and oversight of offshore infrastructure.

For example, Thales Alenia Space is exploring architectures capable of bringing together multiple observation sources to improve understanding, anticipation and protection. Value no longer lies solely in the sensor, but in the ability to turn a succession of measurements into a coherent picture of the situation.

Navigating when satellite signals become unavailable

Maritime navigation depends heavily on satellite signals. Yet these signals can be jammed, spoofed or simply unavailable. An inertial navigation system allows navigation to continue, but its error increases progressively when it can no longer be corrected against an external reference.

The Earth’s gravity and magnetism offer another approach. These natural fields are passive and cannot be jammed. By comparing measurements taken on board with gravity or magnetic maps, a vessel can estimate its position without depending directly on an external signal.

For example, Spectral Flow is working on compact magnetic sensors for this terrain-referenced navigation. Quantum gravimeters offer another promising avenue. Technologies based on cold atoms can provide highly stable measurements, without significant instrumental drift and with reduced calibration.

Other quantum sensors, using Rydberg atoms in particular, could measure radiofrequency fields across a very wide range. They offer potential for communications, radar and resistance to jamming. Their transition from the laboratory to operational equipment nevertheless requires further progress in robustness, stability, bandwidth and miniaturisation.

Seeing the sea beyond conventional imagery

A conventional image primarily provides information about visible shapes and colours. Multispectral and hyperspectral imaging analyse more bands of light. Each pixel can then reveal a signature linked to the composition of the material observed. These technologies make it possible to map shallow waters, assess turbidity, monitor coastal vegetation, distinguish certain habitats and detect pollution. They can also improve vessel protection through better observation at night, in mist or through smoke.

For example, Hytech Imaging combines acquisitions from satellites, aircraft and drones with radiative transfer models.

This combination makes it possible to produce information on bathymetry, water quality, biodiversity and coastal change. The objective is now to move from local campaigns to services capable of regularly processing vast areas.

Polarimetry provides complementary information by studying the orientation of the light field.

For example, Satlantis develops payloads combining several spectral ranges, video and polarimetric filters. This approach can improve correction for atmospheric effects, reduce sun glint on water and reveal texture signatures that are difficult to distinguish in a conventional image.

The potential is particularly significant for detecting hydrocarbons. According to the figures cited in the document, only around 6 per cent of checks performed following certain radar alerts actually confirm pollution. More precise optical and polarimetric characterisation could therefore improve alert assessment before resources are deployed on site.

Designing structures suited to extreme depths

Pressure radically changes design constraints. At a depth of 6000 metres, it approaches 600 bars. Structures must withstand these conditions over time while retaining properties compatible with buoyancy, mass and equipment integration. As an example, FMC Composite presents the principle of a compressible composite hull whose volume changes under pressure to maintain constant buoyant force. This illustrates a change in approach: the aim is no longer solely to resist the environment, but to design a structure capable of adapting to it.

Materials must also address sovereignty challenges. Permanent magnets are essential for motors, generators, acoustic equipment and certain electromagnetic devices. Yet their value chain remains highly concentrated.

According to data presented by HIT Mag, more than 92 per cent of global permanent magnet production comes from China.

European imports are reported to have averaged around 950 million euros a year between 2023 and 2025. The company is therefore developing a new generation of magnets without rare earths, aiming to reduce dependence on critical resources, energy consumption and the carbon footprint.

Producing energy where sunlight and cables are no longer sufficient

Long-duration submerged sensors need a reliable power supply, sometimes for several years. Batteries require costly replacement operations, while cables are not always feasible.

Radioisotope thermoelectric generators offer a solution for the most isolated missions. They directly convert the heat produced by an isotope’s natural decay into electricity. They have no moving parts and do not operate like a nuclear reactor.

For example, Thermagy develops modules intended to facilitate the integration of this technology. Power of a few tens of watts could be enough to supply underwater sensors, acoustic systems or drilling monitoring equipment over the long term.

The physics of conversion may be shared by maritime and space applications, but integration constraints remain different. At sea, the main challenges concern pressure, corrosion, heat transfer, connectors, deployment and recovery. Safety, traceability and end-of-life management must therefore be considered from the design stage.

Convergence based on integration

The most promising innovations do not rely on a single technology.

They combine more accurate sensors, independent navigation, resilient communications, adapted structures, lasting energy supplies and intelligent use of data.

This convergence can improve knowledge of the ocean, strengthen operational safety and support a more autonomous industry. It also requires cybersecurity, industrial sovereignty, energy efficiency and equipment lifecycles to be addressed simultaneously.

The next breakthrough may not come from a new sensor, but from the ability to connect all these building blocks to obtain continuous, reliable and immediately useful information for detecting today’s and tomorrow’s risks.