Editing Mariner program (section)

==Early concept==
The Mariner program began in 1960 with a series of JPL mission studies for small-scale, frequent exploration of the nearest planets.  They were to take advantage of the soon-to-be-available Atlas launch vehicles as well as the developing capability of JPL's Deep Space Instrumentation Facility (later named the Deep Space Network), a global network of ground stations designed to communicate with spacecraft in deep space.<ref name="NASA"/> The name of the Mariner program was decided in "May 1960 – at the suggestion of Edgar M. Cortright" to have the "planetary mission probes ... patterned after nautical terms, to convey 'the impression of travel to great distances and remote lands.'" That "decision was the basis for naming Mariner, Ranger, Surveyor, and Viking probes."<ref>{{Cite web|url=https://history.nasa.gov/SP-4402/ch3.htm|title=chapter 3|website=history.nasa.gov}}</ref>

Each spacecraft was to carry solar panels that would be pointed toward the Sun and a dish antenna that would be pointed at Earth.  Each would also carry a host of scientific instruments.  Some of the instruments, such as cameras, would need to be pointed at the target body it was studying.  Other instruments were non-directional and studied phenomena such as magnetic fields and charged particles. JPL engineers proposed to make the Mariners "three-axis-stabilized," meaning that unlike other space probes they would not spin.<ref name="NASA"/>

Each of the Mariner projects was designed to have two spacecraft launched on separate rockets, in case of difficulties with the nearly untried launch vehicles. Mariner 1, Mariner 3, and Mariner 8 were in fact lost during launch, but their backups were successful.  No Mariners were lost in later flight to their destination planets or before completing their scientific missions.<ref name="NASA"/>