Ground control thumb|alt=A look inside the Mercury Control Center, Cape Canaveral, Florida. Dominated by the control board showing the position of the spacecraft above ground|Inside Control Center at Cape Canaveral (Mercury-Atlas 8) The number of personnel supporting a Mercury mission was typically around 18,000, with about 15,000 people associated with recovery. Most of the others followed the spacecraft from the World Wide Tracking Network, a chain of 18 stations placed around the equator, which was based on a network used for satellites and made ready in 1960. It collected data from the spacecraft and provided two-way communication between the astronaut and the ground. Each station had a range of and a pass typically lasted 7 minutes. Mercury astronauts on the ground would take the role of Capsule Communicator, or CAPCOM, who communicated with the astronaut in orbit. Data from the spacecraft were sent to the ground, processed at the Goddard Space Center by a redundant pair of transistorized IBM 7090 computers and relayed to the Mercury Control Center at Cape Canaveral. In the Control Center, the data were displayed on boards on each side of a world map, which showed the position of the spacecraft, its ground track and the place it could land in an emergency within the next 30 minutes.
Ground control thumb|alt=A look inside the Mercury Control Center, Cape Canaveral, Florida. Dominated by the control board showing the position of the spacecraft above ground|Inside Control Center at Cape Canaveral (Mercury-Atlas 8) The number of personnel supporting a Mercury mission was typically around 18,000 with about 15,000 people associated with recovery. Most of the others followed the spacecraft from the World Wide Tracking Network, a chain of 18 stations placed around the equator, which was based on a network used for satellites and made ready in 1960. It collected data from the spacecraft and provided two-way communication between the astronaut and the ground. Each station had a range of and a pass typically lasted 7 minutes. Mercury astronauts on the ground would take the role, of Capsule Communicator, or CAPCOM, who communicated with the astronaut in orbit. Data from the spacecraft were sent to the ground, processed at the Goddard Space Center by a redundant pair of transistorized IBM 7090 computers and relayed to the Mercury Control Center at Cape Canaveral. In the Control Center, the data were displayed on boards on each side of a world map, which showed the position of the spacecraft, its ground track and the place it could land in an emergency within the next 30 minutes.