Fueled by the fictions in popular culture and scientific speculation, curiosity led to the direct exploration of the Red Planet using robotic spacecraft. Beginning in 1960 with a series of mostly unsuccessful Soviet flyby probes, our exploration of Mars, though fraught with failures, challenges and high costs, has slowly resulted in an accumulation of important scientific discoveries. As a result, we’ve begun to find some answers to questions about water and life on Mars, with each mission bringing us one step closer to the reality of sending humans to Mars.
NASA Mariners: 1962-1973
Although the initial Mariner missions failed, missions 4 through 10 provided several groundbreaking firsts in space exploration. Launched in 1964, Mariner 4, NASA’s first successful Mars flyby provided the first close-up images of a planet other than Earth, and its 22 photos revealed a cratered surface.
Mariners 6 and 7, identical spacecraft launched in 1969, were flyby missions with onboard computers capable of transmitting images 2000 times faster than the Mariner 4. They acquired 201 far-range and close-up images of Mars, which effectively disproved the existence of artificial canals on the surface. Experiments detected atmospheric constituents, temperature and surface pressure data.
Launched in 1971, Mariner 9 dramatically altered what we knew about Mars, providing 54 billion pieces of data, including 7329 images of the planet’s surface and the first high resolution photos of the two Mars moons. Although it was delayed on arrival by dust storms, Mariner 9 showed incredible surface variations, including ancient river beds – feasible evidence of historic water.
Russian Probes: 1969-1973
Although Mars 2 crashed into the Mars surface and Mars 3 only worked for 20 seconds after landing, these Russian probes were the first human artifacts to land on the Red Planet. Of seven flyby, lander and orbiter spacecraft in the series, Mars 5 (1973) succeeded, sending back 60 images of the Martian terrain and information on the temperature, altitude, ozone layer, magnetic field and ionosphere.
NASA Viking Orbiter/Landers: 1975-1982
Launched separately in 1975, Viking 1 and 2 went into Mars orbit in 1976, first imaging the entire surface for viable landing sites, before the landers detached from the orbiters to successfully touch down. The Viking landers provided 1400 images of the Mars surface around the two landing sites, analyzed surface samples for signs of life, studied the atmosphere and measured seismic waves. The first spacecraft to transmit colour panoramic images of the Martian terrain, the Viking spacecraft provided extensive scientific information, including evidence of historic surface water and data on seasonal dust storms, pressure changes and atmospheric gases. Biological experiments, however, showed no signs of life.
NASA Mars Global Surveyor: 1996-present
Launched in 1996 to recover the mission objectives of the failed Mars Observer, the Mars Global Surveyor mapped the topography of the Martian surface, providing high resolution images and vast amounts of data on gravity, weather, climate, atmosphere and the magnetic field. Its detailed photos of topographical features such as gullies suggested the presence of frozen water. Still in use as a data relay long after it’s mission timeline, the Mars Global Surveyor went into an error condition on November 2, 2006.
NASA Mars Pathfinder: 1996-1998
Launched in 1996, the Pathfinder lander arrived on Mars in 1997, releasing the first Mars rover, the Sojourner, to explore the Martian surface and provide data on the feasibility of low-cost landings. This mission proved the viability of a number of new technologies, including airbag landings, and was able to operate under a much smaller budget than previous missions. It also gained widespread public attention. In addition to more than 17,000 images, the mission’s analysis of the Martian atmosphere, climate, geology, rocks and soil provided further evidence of the Red Planet’s watery past. Contact was lost with the lander and rover in late 1997.
NASA Mars Odyssey
Originally planned as an orbiter/lander, the Mars Odyssey was launched as an orbiter-only mission in 2001 to analyze Martian mineral, climate and geological data and study radiation hazards. It served as a communications relay and source of information on atmospheric conditions for other missions such as the Mars Reconnaissance Orbiter, and its mission had been extended through 1998 for further observation of seasonal changes in polar ice, clouds and dust storms.
European Space Agency Mars Express
Although contact with its lander, the Beagle 2 was lost, the Mars Express Orbiter, launched in 2003 to obtain high resolution imagery for geological analysis and conduct mineralogical and atmospheric mapping, has discovered the presence of hydrated sulphates, silicates and rock-forming minerals on Mars. In addition to detecting methane in the atmosphere, suggesting volcanic or hydrothermal activity or perhaps even the presence of subsurface microorganisms, it discovered buried impact craters and confirmed the presence of underground water-ice.
NASA Mars Exploration Rovers (MER)
Spirit and Opportunity, the two Mars Exploration rovers launched in 2003 have analyzed Martian rocks and soil in the search for geological clues and measurable data about water on Mars, as well as information about future landing sites. Equipped with advanced instrumentation, including cameras for panoramic photos, navigation and hazard-avoidance, as well as X-ray spectometers, the rovers have provided evidence of historic water, including rock stratification and the distribution of chlorine and bromine along what must have been a former salty sea. The mission has been extended through to September 2007.
NASA Mars Reconnaissance Orbiter
Designed to orbit Mars for more than a Martian year, the Mars Reconnaissance Orbiter was launched in 2005 and has been in orbit since spring 2006. This multifunction spacecraft is gathering data on Martian landforms, weather and surface conditions with six advanced technologies, including a high resolution imager. In addition to collecting information on possible landing sites, the orbiter is testing an improved telecommunications system that will become a relay station for future missions.
The Mars Curse:
Despite these achievements, to date almost half of Mars missions have failed, a phenomenon Time magazine journalist Donald Neff described as the Mars Curse. Although this has fueled some far-fetched speculations, including one involving a galactic probe-eating ghoul, scientists have conducted detailed investigations as to why each mission failed.
|Mission Name||Mission type||Date||How it failed|
|Marsnik 1 and 2 (aka Mars 1960A/1960B)||Flybys||1960||Launch failure.|
|Sputnik 22||Flyby||1962||Broke up in Earth orbit.|
|Mars 1||Flyby||1962||Contact lost.|
|Sputnik 24||Lander||1962||Broke up during transfer to Mars trajectory.|
|Mariner 3||Flyby||1964||Protective shield failed; solar batteries died.|
|Zond 2||Flyby||1964||Contact lost.|
|Mars 1969A and Mars 1969B||Orbiters||1969||Launch failure.|
|Mariner 8||Flyby||1971||Launch failure.|
|Cosmos 419||Orbiter/lander||1971||Bad ignition timer setting.|
|Mars 7||Lander||1973||Lander separated early and missed the planet.|
|Phobos 1||Orbiter/lander||1988||Software error resulted in deactivation of solar paneled thrusters; batteries died.|
|Mars Observer||Orbiter||1992||Contact lost.|
|Mars 96||Orbiter/lander||1996||Failed in Mars trajectory; re-entered Earth’s atmosphere.|
|Nozomi||Orbiter||1998||Mars orbit insertion burn failed; flew past Mars.|
|Mars Climate Orbiter||Orbiter||1998||Destroyed due to navigation error during Mars orbit insertion.|
|Mars Polar Lander||Lander||1999||Contact lost.|
|Deep Space 2 (DS2)||Penetrators||1999||Unknown: contact lost after landing.|
|Beagle 2 (part of Mars Express)||Lander||2003||Contact lost.|