An Atlas II rocket takes off from the Cape Canaveral Air Force Station carrying a communications satellite for the United States Navy. The satellite is part of the Navy's global communications network.

Among the different reasons for sending space probes and satellites into orbit is the use of the space environment for defensive purposes. Military equipment such as missiles, rockets, and communications systems were among the first hardware used in the early space programs. Gradually, civil and commercial space projects developed their own purpose-built spacecraft. But the military continues to have a dominant place in the space programs of the United States, China, and Russia. The principal launching sites for rockets in all three countries are military bases, and military ships and planes are used for tracking and communications during rocket launches.

The French commercial launching site in Kourou, French Guiana, had its origins as a...