Sharing The Ride Around The World
As the flights of Project Mercury were planned, we knew we need uninterrupted communication with man and machine as they flew around the world. Life support systems, speed, attitude, position - a thousand bits of data - had to be watched continuously to get the "A-OK" signals that punctuated the entire race to the Moon for a watching world. Mission Control had to be the world's biggest earthbound dashboard - an unfailling connection to every craft we sent aloft - each instrument watched by a hundred pairs of expert eyes.
To do the job, NASA built 13 strategially located stations around the world, creating the first Global Communication Network. State of the art technology for its time, the system grew to become a vital part of the most sophisticated Galatic communications network on Earth by the time the Apollo missions to the Moon were completed.
From: Wikipedia
Mission Control Center (NASA)
NASA's Mission Control Center (MCC-H), also known by its callsign, Houston, at the Lyndon B. Johnson Space Center, in Houston, Texas manages all manned space flight of NASA, including the U.S. portions of the International Space Station (ISS). From the moment a spacecraft clears its launch tower until it lands on earth, it is in the hands of Mission Control. The Mission Control Center houses several Flight Control Rooms, from which flight controllers coordinate and monitor the spaceflights. The rooms have many computer resources to monitor, command and communicate with spacecraft. When a mission is underway the rooms are staffed around the clock, usually in three shifts.
In the United States, the Mission Control Center is associated with manned space flight. A separate organization called the Jet Propulsion Laboratory and its control room manage unmanned space probes. Because Houston is a hurricane sensitive area, NASA has basic back-up facilities for shuttle operations at the Kennedy Space Center as well as a back-up location at MCC Moscow for ISS operations.
Before Gemini 4, all Mercury–Redstone, Mercury–Atlas, and the unmanned Gemini 1, Gemini 2, and manned Gemini 3 missions were controlled by the Mission Control Center at Cape Canaveral Air Force Station, Florida. The original MCC at Cape Canaveral is at the east end of Mission Control Road, about 0.5 mile (0.8 km) east of Phillips Parkway. This building is used as a storage facility, and is scheduled for demolition before 2011. It was formerly part of the visitors' tour, but all control-room equipment was removed in the late 1990s to the Kennedy Space Center Visitors Complex. A replica of the control room, with all the original equipment, is open during Visitors Complex hours.