Z ZSQSGSGKGKXRGOQOS DNQ XZARZXAVAQQVA XXDRDZ QSGIGKGKXRGOQOX DXQ XZAIZXAVQQKDZ XXDRDDDRZ DXQ XZAIZAZVAQQZDZXXDLKKDRA Z DSQSGIGGGQXRDN G XXDRZSDRA Z DSQSGIGGGQXRGLZOX DXQ XZAIZAZV QSGIGGGQXRGLZOX DXQ XZAIZGAVAQQSXZXXDRDZDRA DXQ XQAIZGAVQQKVA XXDRDZDRANGDSSQSGIGGGQXRDI Z XXDRDDDRZLQ ZSQSGIGGGGXRGVZOA DNQ XZARZGAV QSGIGGGGXRGVQOA DNQ XZARZGAVQKZZAZXXDRZDDRA DNQ XZARZAZVAKDDGZXXDRDADIZLA DSQSGIGGGGXRGZ SZXXDRDDDRXOS DSQSQIGGGGXRDDZOA DNQ XZARZXAV QSGSGGGGXRDSQOG DXQ XZARZXAVAKDZDZXXDRDLDRA DXQ XZARZXAZZKZZDZXXDLKADRA Z DSQSGIGGGGXRGX GZXXDRZXDRZ Z DSQSAQGGGGXRDAZOG DXQ XZAIZAZV DRDXDRA Z DSQSGIGGGGXRDGSOG DXQ XZAIZAZVQKZS OGGGXRDGAOG DXQ XZAIZAZVQKZVA XXDRDZDRANGDSS XZAIZXAZZKZZD XXDRDLZDZHA DSQSGIGGGGXRDQAOQ DLKADRKHQ ZSQSGIGGGGXRDKZOQ DXQ XZAVZAAVQKZZ GGGGXRS ZOQ DXQ XZAIZAZVQKZDG XXDRDSDIZ A ZS XZAIZAZVQQKSX XXDRDDDRZNS ZSQSGIGGGGXRSOAOQ DRDZDRANGDSSQSAQGGGGXRSOAOK DNQ XZAVZAAVQQKZ GGGGXRSNZOK DNQ XZAIZAZZSQQZSZXXDLKADRA Z DS XZAIZGAVQQKZG XXDRZXDRZ Z DSQSAQGGGGXRSLAOK DRDSDRZ Z DSQSAQGGGGXRSLAOK DNQ XZAIZAZZZQKS GGGGXRSLAOK DNQ XZAIZAZZZQKVA XXDRDZDRANGDSS XRSIZHZ DXQ XZAIZAZZZQKQQZXXDRDNDRZNQ DSQSGS ZXAZSQQZXZXXDLKQDRSQS ZSQSGIGGGQXRSVAHZ DXQ [Illustration: _Messages are received and routed at the JPL Communications Center._] [Illustration: _Data are routed to the digital computer at JPL._] [Illustration: _Printout data are made available to experimenters._] [Illustration: _Spacecraft status is posted in Operations Center._] The Mobile Tracking Station in South Africa used the Johannesburg communication facilities. Two one-way circuits for testing and control purposes were open to Cape Canaveral from a month before until after the spacecraft was launched. Lines from the Communication Center to the Space Flight Operations Center at JPL terminated in page printers and reperforators in several locations. Voice circuits connected all of the stations with Operations Center through the Communication Center. Long-distance radio telephone calls were placed to South Africa to establish contact before the launch sequence was started. Woomera used the Project Mercury voice circuits to the United States during launch and for three days after. THE OPERATIONS CENTER The actual nerve center of the Mariner operation was the Space Flight Operations Center (SFOC) at Pasadena. Here, technical and scientific advisory panels reported to the Project Manager and the Mariner Test Director on the performance of the spacecraft in flight, analyzed trajectories, calculated the commands for the midcourse trajectory correction, and studied the scientific aspects of the mission. These panels were a Spacecraft Data Analysis Team, a Scientific Data Group, an Orbit Determination Group, a Tracking Data Analysis Group, and a Midcourse Command Group.