AAC Clyde Space has started building two more satellites for its maritime data services, taking the number of new Sedna spacecraft planned for launch in 2027 to four.
Sedna-5 and Sedna-6 join Sedna-3 and Sedna-4, which are already under construction and the company says the expanded fleet is intended to increase the volume and frequency of space-based maritime data available to customers, improving coverage and service resilience.
A larger orbital watch on shipping
AAC Clyde Space currently has five satellites supporting its maritime services; AprizeSat-8, Sedna-1, Sedna-2, Thea and Ymir-1 and the company expects to have almost doubled that number by the end of 2027.
“This investment is part of the broader transformation of AAC Clyde Space and shows how we can now move faster to scale our Data & Services business. By the end of 2027, we expect to have almost doubled the number of satellites supporting our maritime services. This puts us in a stronger position to meet the high demand we already see in the market.”
says
The Sedna satellites collect Automatic Identification System data from vessels. AIS is a radio system that broadcasts a ship’s identity, position, course, speed and navigational status which other ships and coastal authorities use to improve situational awareness and reduce collision risk. Satellite receivers extend that picture beyond the range of land-based antennas.
From collision avoidance to maritime intelligence
AIS began when the International Maritime Organization adopted performance standards in 1998 and adopted carriage requirements in 2000. Those rules covered passenger ships of any size, cargo ships of 300 gross tonnes and above on international voyages and certain other larger ships and were fully in force by the end of 2004.
What started as a bridge-to-bridge safety tool is now a major input to maritime intelligence. Data services combine satellite and terrestrial AIS feeds to support vessel traffic management, search and rescue, port operations, fisheries monitoring, marine insurance, supply-chain visibility and environmental enforcement. The value comes from connecting positions over time with information about ports, cargoes, weather, ownership, imagery and other data sources.
Why some vessels disappear from the picture
Ships covered by the rules are generally expected to keep AIS operating, although the IMO allows exceptions where protection of navigational information is necessary. A master may switch it off where there is a credible risk from pirates or terrorists. Not every vessel is required to carry AIS in the first place. Smaller craft, many fishing boats and some government vessels can be outside the carriage requirement.
Some operators may also deliberately disable or manipulate AIS to hide activity. That can be associated with unreported fishing, sanctions evasion, unauthorised transhipment or other conduct that benefits from avoiding scrutiny. An AIS gap alone does not prove intent as satellite coverage varies, shore receivers need line of sight and messages can be lost where vessel density creates interference. Analysts therefore need to test gaps against reception conditions and other evidence before drawing conclusions.
Why extra capacity matters
For maritime users, more spacecraft can create more opportunities to receive vessel signals and can make a service less dependent on any one satellite. That matters most where decisions depend on regular updates rather than a single location point.
AAC Clyde Space has not disclosed launch dates and other technical details that will determine how much the extra capacity will be added to their service in practice but the decision to proceed with Sedna-5 and Sedna-6 is a tangible fleet investment. It underlines that dependable data delivery is as important to maritime intelligence as the analytics layered on top.
Sources AAC Clyde Space press release, International Maritime Organization AIS guidance and Global Fishing Watch data caveats.