The unmanned spacecraft at an altitude of 6,000 feet and sends back to Earth the first close-up images of the red planet.
Launched in November 1964, Mariner 4 carried a television camera and six other science instruments to study Mars and interplanetary space within the solar system. Reaching Mars on July 14, 1965, the spacecraft began sending back television images of the planet just after midnight on July 15. The pictures–nearly 22 in all–revealed a vast, barren wasteland of craters and rust-colored sand, dismissing 19th-century suspicions that an advanced civilization might exist on the planet. The canals that American astronomer Percival Lowell spied with his telescope in 1890 proved to be an optical illusion, but ancient natural waterways of some kind did seem to be evident in some regions of the planet.
Once past Mars, Mariner 4 journeyed on to the far side of the sun before returning to the vicinity of Earth in 1967. Nearly out of power by then, communication with the spacecraft was terminated in December 1967.