20 August 1975: The Viking 1 space probe was launched from Kennedy Space Center, Cape Canaveral, Florida, aboard a Titan IIIE/Centaur rocket. For the next ten months it traveled to Mars, the fourth planet of the Solar System. Once there, it was placed in orbit and began sending telemetry data back to Earth. A Viking Lander descended to the planet’s surface, landing at Chryse Planitia.
This was the first time that a spacecraft had landed on another planet. The orbiter continued to operate over the course of 1,485 orbits. As it ran low on fuel, mission controllers boosted it into a higher orbit to prevent it falling to the planet. Orbiter operations were terminated 17 August 1980. The lander operated for 6 years, 116 days, before the mission was terminated by a faulty transmission which resulted in a loss of contact, 11 November 1982.
14 July 1965: At 8:00:57 a.m., EST, 7 months, 14 days after its launch from the Kennedy Space Center, the space probe Mariner 4 made its closest approach to Mars. It came within 6,080 miles (9,846 kilometers) of the surface and took 21 full digital images and a portion of a 22nd. These images were stored on magnetic tape and later transmitted to Earth. 5.6 million bits of data were received.
Mariner 4 was a 574 pound (260.68 kilogram) interplanetary spacecraft, controlled by radio signals from Earth. It was launched 28 November 1964 from Launch Complex 12 at the Kennedy Space Center, Cape Canaveral, Florida. The launch vehicle was a three-stage liquid-fueled Atlas D/Agena rocket. Mariner 4 continued to perform experiments and send signals back to Earth until 21 December 1967. It was 192,100,000 miles (309,154,982.4 kilometers) from home. Today, it is in orbit around the sun.
25 January 2004: Mars Exploration Rover–B, named Opportunity, landed in a crater at Meridiani Planum on the surface of Mars at 5:05 a.m., UTC SCET (Spacecraft Event Time) and rolled into a small crater, approximately 22 meters in diameter.
The crater would later be named Eagle Crater, and the landing site is named Challenger Memorial Station. The site is on the opposite side of the planet from Opportunity‘s twin, MER-A, Spirit.
4 January 2004, 04:35 Ground UTC: The NASA Mars Exploration Rover A, named Spirit, landed on the surface of Mars within the large impact crater Gusev. The location of touch down and the starting point for the rover’s exploration of Mars is named Columbia Memorial Station.
28 November 1964, 14:22:01 UTC, T minus Zero: Mariner 4, a space probe designed and built by the Jet Propulsion Laboratory (JPL), lifted off from Launch Complex 12 at the Cape Kennedy Air Force Station, Cape Kennedy, Florida. The launch vehicle consisted of an Atlas LV-3 and an Agena D.
The mission of Mariner 4 was to “fly by” Mars to take photographic images and gather scientific data, then relay this to tracking stations on Earth.