ESA transmits satellite images in near real-time via Space Data Highway
The European Space Agency (ESA) has successfully linked up the Sentinel-1A and Alphasat satellites via laser, transmitting data across almost 36,000 km (about 22,400 miles) of space. The link allows for the delivery of data to Earth in near real time, and will be used for a wide range of applications including the timely monitoring of natural disasters.
The Sentinel 1A satellite was launched in April 2014, and is the first of a fleet that will form the ESA’s Copernicus environment monitoring program. It orbits from pole to pole at 700 km (435 miles), and is designed to provide essential data for applications such as natural disaster relief, supporting maritime border control and even tackling piracy and drug smuggling.
The biggest downside to the system is its reliance on transmitting data only when it passes over its ground stations in Europe. The Space Data Highway, also known as the European Data Relay System (EDRS), aims to solve this issue by transmitting the data to the geostationary Alphasat – Europe’s largest telecommunications satellite. The second satellite is constantly in view of its ground station, meaning it can stream images back to Earth with only minimal delay. The link operates at 1.8 Gbit/s, and is designed to be scaled up to 7.2 Gbit/s as the program advances.
The below image of Berlin is one of the first to be transmitted via the link.
At present, it takes a great deal of work and coordination to line up the satellites to make the laser link possible, but the process will eventually be routine and fully automated. While much of the bandwidth will be used by the ESA for its Earth observation projects, it will also make other tasks, such as the ocean surveillance, much more effective thanks to the faster relaying times.
Just this week the Sentinel-1A has been used to observe the Fogo volcano, which has been erupting in Cape Verde since November 23. The satellite has been using radar scans to track the underground flow of lava, identifying the movement of molten rock towards the surface, with warnings provided accordingly.
Once the EDRS system is fully operational, the data reporting process will be near real time no matter where on the planet the event is occurring, allowing for more efficient monitoring.
Check out the video below for an illustration of the cutting-edge process.