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Mars: The Spacecraft Graveyard
Mars has been a popular target for unmanned spacecraft since the dawn of the space age. Numerous attempts have been made to set human-built probes into orbit around the red planet and land them on its surface to find out more about our ruddy neighbor, particularly if it carried signs of life.
The first attempt to send a probe to the Red Planet was made by the USSR in 1960 with the "Marsnik" spacecraft, which failed along with many subsequent missions. A total of six landers or rovers and nine orbiters have been sent to Mars. [A Great Telescope for Mars: The celestron NexStar 130SLT]
Only three orbiters and one rover are currently still probing the planet. The spacecraft that have ended their missions – from the first success of Mariner 9 to the Phoenix Mars Lander and Spirit rover – remain dormant in orbits circling the planet or silent at the spot where they landed on the surface.
Here, SPACE.com takes a look at the dead spacecraft of Mars and their missions, whether completed or ended before they could begin.
FIRST STOP: Mariner 9
Mariner 9Slide 2 of 21
Mariner 9When it reached Mars on Nov. 13, 1971, Mariner 9 became the first spacecraft to orbit another planet, just edging out its Soviet competitor, Mars 2.
Mariner 9 mapped 85 percent of the surface of the planet, revealing volcanoes (including the first detailed images of Olympus Mons, the largest volcano in the solar system), huge canyons (including Valles Marineris, named for the spacecraft) and valleys that resembled dry riverbeds. A dust storm was raging when the probe first arrived at the planet, obscuring the surface, but it eventually abated, allowing Mariner 9 to take the highest resolution pictures of the Martian surface up to that time. The spacecraft transmitted more than 7,000 photos of the red planet back to Earth. It also made the first detection of water vapor on Mars, over the planet's south pole. The spacecraft remained in operation in its orbit until contact was lost on Oct. 27, 1972.
The spacecraft was left in an orbit that would take 50 years to decay, after which it will enter Mars' atmosphere.
NEXT: Mars 2 and 3Slide 3 of 21
Mars 2 & 3Slide 4 of 21
Mars 2 & 3These identical Soviet missions each consisted of an orbiter and a lander were the first human-built craft to impact the Martian surface.
While the Mars 2 orbiter worked from the time it entered its orbit in December 1971 until Aug. 22, 1972, the lander crashed on the surface and was lost. The orbiter's mission was to study the topography and composition of the Martian surface, as well as the planet's atmosphere and magnetic field. Mars 3's mission was also declared complete on Aug. 22, 1972, after its orbiter had made 20 orbits of the planet (Mars 2 had made 362) after its orbital insertion on Dec. 2, 1971.
The Mars 3 lander made it to the surface of the planet, but communication stopped about 20 seconds after landing due to damage from the dust storm raging at the time. Both orbital probes sent back a total of 60 images and returned data on the surface temperature, surface air pressure and water vapor concentrations of the atmosphere of Mars.
NEXT: Viking 1 and 2Slide 5 of 21
Viking 1 & 2Slide 6 of 21
Viking 1 & 2Though the Soviet landers had made it to the surface first, Viking 1 was the first probe to land on the surface of Mars and perform its mission when it touched down on Mars' Chryse Plain in July 1976. Viking 2 (pictured) followed on Sept. 3 landing on Utopia Plain on the opposite side of Mars.
Both missions included an orbiter and a lander. Viking 1 sent the first color pictures of the Martian surface, which showed the red planet's rust-colored terrain and ruddy sky.
Both landers scooped up Martian dirt to analyze it for biological signature, but found none, though some continue to debate those findings. The Viking orbiters and landers transmitted over 50,000 photos of Mars and a treasure trove of scientific data that is still being analyzed.
NEXT: Pathfinder and SojournerSlide 7 of 21
Mars Pathfinder & SojournerSlide 8 of 21