One of the first ever uses for satellites continues to be important to this day, communication. Satellite communications technology has supported military and civilian communications for over 50 years.
All satellites share information by sending electromagnetic signals to satellite receivers, and many also receive instructions in the same way. For communications satellites sending and receiving information is their primary purpose.
Satellite signals allow faster communication between two points on the Earth’s surface by reflecting and redirecting signals in straight lines. They also allow people to send or receive information in remote areas where there is no wired infrastructure. Satellite telephone communication is an obvious example, but they can also send television signals, encrypted information, military instructions, and even financial transactions.
Thanks to multiple networks of communications satellites, information can spread around the world nearly instantaneously. Before they existed, this wasn’t possible. Physical recordings of events had to be sent via courier in order to be shared on national television or in cinemas. Communications satellites have changed how connected people in different countries feel to one another. Seeing iconic moments happen in near real-time on live television, such as the fall of the Berlin wall in the second half of the 20th century, changed people’s expectations of how international news could be shared.
It is estimated that over 50% of the Earth’s population does not currently have reliable access to the internet. Many government and private companies are launching satellite constellations specifically to enable these people to access reliable satellite broadband wherever they are.
Working together in emergencies
There are times when the need for communication is more urgent. Natural disasters like floods, earthquakes, wildfires and landslides create rapidly changing and dangerous situations on the ground, cutting off communities and leaving people in need of rescue. Satellites can swiftly gather up-to-the- minute information in the aftermath or even during disasters, helping governments to limit the risks to rescuers and arrange relief efforts. There are even special networks of satellites called ‘clusters’ that are operated from different countries, which can switch over into working together in the case of a disaster.
The Disaster Monitoring Clusters are a fantastic example of international co-operation in space.