1964 November 28, Atlas-Agena D Mariner 4 (Nasa): First successful Mars mission. Passed the red planet at 9825 km on July 14, 1965, and returned 22 TV pictures of its surface. Discovered the cratered nature of Mars' surface.

Mariner 4 gave scientists their first glimpse of Mars at close range, passing over the planet at an altitude of 9,846 kilometers (6,118 miles) above the surface and putting to rest the myths of the late 19th century that the planet may have harbored an advanced civilization. Launched on November 28, 1964, Mariner 4 carried a television camera and six other science instruments to study interplanetary space between the orbits of Earth and Mars and in the vicinity of Mars itself.

The spacecraft took 22 television pictures covering about 1 percent of Mars's surface, which revealed a vast, barren wasteland of craters strewn about a rust-colored carpet of sand. The canals that Percival Lowell had spied with his telescope in 1890 proved to be an optical illusion, but natural waterways of some kind seemed to be evident in some regions of the planet. Other experiments measured atmospheric density and the interplanetary medium.

Once past Mars, Mariner 4 journeyed on to the far side of the Sun before returning to the vicinity of Earth again in 1967. Nearly out of power by then, engineers decided to use the aging craft for a series of operational and telemetry tests to improve their knowledge of the technologies that would be needed for future interplanetary spacecraft. All operations of the spacecraft ceased on December 20, 1967.

1975 August 20, Titan IIIe - Centaur - TE 364-4 Viking 1 (Nasa): Orbiter and lander mission (a Viking craft is shown in the image; the lander is sitting above the orbiter, packed in the protection cover). The spacecraft reached Mars orbit on June 19, 1976, the lander softlanded on Mars on July 20, 1976, in Chryse Planitia at 22.48 d North areographic latitude, 48.01 d Western longitude. Both orbiter and lander performed extremely successful missions, but the lander's bio experiments returned ambiguous results concerning microbiotic life on Mars. Viking Orbiter 1 was successfully working until August 7, 1980, when it went out of altitude control propellant, Viking Lander 1 until November 13, 1982 when it was accidentally shut down.

1975 September 5, Titan IIIe - Centaur - TE 364-4 Viking 2 (Nasa): Orbiter and lander mission. Reached Mars orbit on August 7, 1976, lander softlanded on September 3, 1976, in Utopia Planitia 47.97 d N, 225.74 d W, 7,420 km North-East of Viking 1. Both Viking 2 orbiter and lander were equally successful as the sister craft Viking 1; Viking Orbiter 2 was active until July 25, 1978, when its altitude control propellant had been used up, Viking Lander 2 returned data up to August 7, 1980, when Viking Orbiter 1 was shut down, which had been served as communications relay.

Both Viking missions were extremely fruitful in both the quality and the quantity of accquired data: The orbiters collected some 52,000 images and cartographed 97 per cent of the Martian surface from orbit, often from different angles so that the topography could be determined. The landers returned some 4,500 photos and weather data from the Martian surface, documenting seasonal changes, besides the well-known soil investigations and bio experiments.

1996 November 7, Delta II Mars Global Surveyor (Nasa): Mars orbiter, launched from KSC, Cape Canaveral. Reached Mars and successfully entered Mars orbit on September 11, 1997. Uses aerobraking for achieving the low Mars orbit required for the intended orbital investigations of the Red Planet, to begin in early 1998.

1996 December 4, Delta II Mars Pathfinder (Nasa); renamed Carl Sagan Memorial Station after landing: Mars lander with Sojourner rover. Launched from KSC, Cape Canaveral; softlanded on Mars on July 4, 1997, in direct approach, in Ares Valley, at 19.5 d N, 32.8 d W.

Sojourner was released to the Martian surface on July 6, and performed investigations of Martian soil and rocks around MPF. Both spacecraft operated extremely successful until the last data transmission on September 27, 1997, and after a last signal received on October 7, 1997, contact was lost, perhaps because of battery failure partially due to falling temperatures at the landing site.

1965 July 18, A2-e Zond 3 (USSR): Flight to Mars orbit (not the planet). Transmitted 25 images of the lunar far side, communication from up to 31 million km,

1969 February 24, Atlas-Centaur Mariner 6 (Nasa): Successful fly-by at 2120 miles (3410 km) occurred on July 31, 1969. Returned data and 75 photos, mainly from the equatorial region. Found that most of Mars' atmosphere was made of carbon dioxide.

1969 March 27, Atlas-Centaur Mariner 7 (Nasa): Successful fly-by at 2190 miles (3524 km) on August 5, 1969; returned data and 126 photos, flying over the south polar region. Was probably struck and slightly damaged by meteor a few days before arrival.

1971 May 30, Atlas-Centaur Mariner 9 (Nasa): Successfully achieved Mars orbit of 850 x 10,650 miles (1390 x 17,140 km) to become Mars' first artificial satellite, and returned 7,329 TV pictures covering the entire surface of Mars, providing the first full photographic atlas, or photo globe, of a celestial body, until it was shut down on October 27, 1972 after 698 orbits, or 349 days in orbit (a total mission of 515 days). Discovered volcanoes, flow channels, and more surface structures.

1960 October 14, A2-e (Mars 60B), also Koralb 5 (USSR): Failed to achieve Earth orbit.

1962 October 24, A2-e Sputnik 22, also Mars 62A or Koralb 11 (USSR): Failed to leave Earth orbit (blew up)

1962 October 24, A2-e Mars 1 (USSR): First probe to pass Mars (at about 190,000 km), but contact lost on March 21, 1963

1962 November 4, A2-e Sputnik 24, also Mars 62B or Koralb 13 (USSR): Failed to leave Earth orbit (blew up)

1964 November 5, Atlas-Agena D Mariner 3 (Nasa): Launched by Atlas-Agena D, Mariner 3 went into Solar orbit, but as the aerodynamic protection shroud failed to be jetisoned, it reached a wrong orbit and failed Mars by a wide margin.

1964 November 30, A2-e Zond 2 (USSR): Passed Mars at less than 1000 miles (1500 km) on August 6, 1965, but communications was lost on May 4 or 5, 1965, so no data were returned.

1967 March 27, A2-e (unnamed Mars ?) (USSR): Launch Failure.

1969 March 27, D1-e (Proton) (Unnamed Mars 69A) (USSR): Failed to achieve Earth orbit.

1969 April 14, D1-e (Unnamed Mars 69B) (USSR): Failed to achieve Earth orbit.

1971 May 8, Atlas-Centaur Mariner 8 (Nasa): Due to second stage failure of the launcher, fell into Atlantic.

1971 May 10, D1-e Cosmos 419 (USSR): Intended orbiter/lander mission, failed to leave Earth orbit.

1971 May 19, D1-e Mars 2 (USSR): The Mars 2 Orbiter reached Mars orbit of 860x15,500 miles (1380x25,000 km) successfully on November 27, 1971. The lander became the first human-made object to reach the surface of Mars when it crashed on the planet on the same day. Because of a global dust storm at arrival time, the orbiter could return only pictures with little surface detail.

1971 May 28, D1-e Mars 3 (USSR): The Orbiter reached Mars orbit (930x124,000 miles, 1500x200,000 km) successfully on December 2, 1971. The lander achieved the first soft landing on Mars on the same day (at 45 deg S, 158 deg W, between Electris and Phaetontis regions), but failed after 110 seconds after transmitting a small portion of a picture. Together with the images returned by Mars 2, a color picture of the global dust storm of December 1971 was composed.

1973 July 21, D1-e Mars 4 (USSR): Intended Mars orbiter; arrived at Mars on February 10, 1974, but failed to get inserted in Mars orbit, and passed by the planet at 2240 km.

1973 July 25, D1-e Mars 5 (USSR): Reached Mars orbit on February 12, 1974, but failed 10 days after orbit insertion, after returning some photos.

1973 August 5, D1-e Mars 6 (USSR): Lander spacecraft; crashed on Mars on March 12, 1974.

1973 August 9, D1-e Mars 7 (USSR): Intended lander, missed Mars by 1280 km on March 9, 1974.

1988 July 5, D1-e Phobos 1 (USSR): Intended to investigate Mars' moon Phobos, this craft lost contact midway on September 2, 1988 because of an erroneous control command sequence.

1988 July 12, D1-e Phobos 2 (USSR): Successfully reached Mars orbit on January 29, 1989, and returned data and photos of Mars and Phobos. During an approaching manoeuver to Phobos, the craft lost orientation due to computer defect, and suffered energy loss, which terminated the mission.

1992 September 25, Titan IIIe-TOS Mars Observer (Nasa): Reached Mars on August 21, 1993, and sent some TV images on approach. Contact was lost during its orbit insertion ignition; it may have been damaged, blewn up, or simply frozen after having lost orientation.

1996 November 16, D1-e Mars 96 (Russia): intended Mars orbiter with 4 landers and 2 penetrators; experiments from 22 countries. Failed to leave Earth orbit, and decayed soon after liftoff.

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