The Complete History Of Mars Exploration Explained

Since humans have looked up to the cosmos, Mars has been an ill‐omen that haunted the night sky. Named after the Roman God of war, Britannica tells us that this planet has long been associated with the brutalities of conflict. Even the earlier Babylonians did not look kindly upon the Red Planet, calling it Nergal after their god of pestilence and death.

For much of history, Mars was shrouded in mystery and a source of much speculation. As technology improved, the planet's secrets slowly became revealed. Mars was found to be a little more than half Earth's size but less dense so that objects on Mars weigh about a third of what they do on Earth. Suspected canals and landscape that seemed facelike were seen that caused some to ponder whether there was life. In fact, in modern times Mars became a predominant fixture in popular culture. H.G. Wells' "War of the Worlds" featured a Martian invasion of Earth. Edgar Rice Burroughs uses Mars as the setting for the adventures of John Carter.

It was only in the mid-20th century that our thirst for accurate knowledge of the Red Planet started to be slaked. This all began at the height of the Cold War.

While the Soviets were coping with failed missions, NASA turned to the Mariner program. Britannica explains that Mariner was the name given to probes that explored the inner planets of the solar system, including Mercury, Venus, and of course the Red Planet. While Mariners 1 and 2 were probes bound for Venus (only Mariner 2 was successful), Mariner 3 was slated to go to Mars. This spacecraft made liftoff, but it quickly lost contact with Earth. Determined, NASA launched Mariner 4 on November 28, 1964. This was a success for NASA as the probe flew by Mars on July 14, 1965, at a range of just over 6,116 miles. Mariner 4 gave humanity the first close up photos of the Red Planet, as well as collect other scientific data. 

While Mariner 4 only photographed 1% of the Martian surface, it was still eye-opening for the public and a clear victory for NASA. They followed up this up with new Mars missions, with Mariners 6, 7, and 9 returning clear and awe-inspiring images of the planet between 1969 and 1971. 

By 1971, the Soviets were smarting from the results of the Space Race as it had only been two years since the U.S. landed its astronauts on the moon. That year, they obtained a half success in Martian exploration. On December 2, 1971, the Soviet Union's Mars 3 had achieved orbit around the Red Planet. Discover Magazine explains how the orbiter released a lander unit whose aim was to reach the surface. As NASA notes, its primary mission was to take scientific data of the atmosphere, collect samples, and analyze other data. But from a political point of view it would be great PR to capture the first surface images of Mars. The rover, called PROP-M, was described by NASA as being a robot tethered to the main lander on skis, which enabled a very constricted range of no more than 49 feet.

The lander touched down successfully with shock absorbers protecting the scientific instruments. The lander's covers opened, and after 90 seconds transmissions began. For all of 20 seconds it seemed a great success, but then quite suddenly communications ceased. The only image that came through was a grainy panoramic that may even just be static. The Planetary Society argues that the lander likely encountered a tremendous sandstorm that overturned the capsule.

After the Viking Program, NASA's historic mission log of Martian exploration shows there was a long pause, with only the Soviets sending two spacecraft to Mars' moons, which failed. Perhaps it was because of the criticisms of the costs of the Viking program that NASA did not attempt to send another spacecraft to Mars until 1992, as per NASA's Mars Exploration Program. That year saw the launch of Mars Observer, which was more or less a converted commercial satellite. According to Space.com, this spacecraft cost $813 million, about four times the original budget. Unfortunately, Mars Observer spun out of control before achieving orbit in 1993. The cause was a likely fuel tank rupture, so NASA reassessed its strategy.

Meanwhile, NASA developed its Mars Global Surveyor mission. This probe attained Martian orbit on September 12, 1997. This mission sent back detailed images of the planet and using a laser altimeter, mapped almost the entire surface. In fact, in some places they were more accurate than what had been mapped on Earth. By February 1, 2001, when its primary mission was over, Global Surveyor had sent 83,000 images back to Earth. The indefatigable spacecraft also lasted far longer than what was anticipated. It only lost contact with NASA in November 2006.

With pressure on NASA's budget, it adopted a "faster, better, cheaper" approach to space exploration, as per "Faster, Better, Cheaper," by Howard E. McCurdy. One of its first missions under the new strategy was Mars Pathfinder. As recounted by the Planetary Society, the program, which cost a relatively low $485 million, aimed to set down a lander named "Pathfinder" on the Martian surface complete with a rover named "Sojourner." This would be the first landing on Mars since the Viking program.

According to NASA, Pathfinder launched on December 4, 1996, and successfully landed on the Red Planet in the rocky plains area of Ares Vallis on July 4, 1997, using airbags. Sojourner was released without a hitch and slowly inspected the surrounding area for three months, reports the Plantery Society. While the mission was billed as a demonstration of technology — and in this regard it was highly successful in showing how Martian exploration could be conducted — it also revealed important scientific information. For example, the morphology of the rocks suggested the presence of running water in the past, as well as magnetism in the planet's dust particles that may have been pushed to the surface through a water cycle. All of this hinted that the planet may have been habitable in the past.

It seems that the success of Mars Odyssey began to open the floodgates to Martian exploration. Britannica describes how the European Space Agency entered the fray with its Mars Express program, which attained orbit on December 25, 2003, and started taking even more detailed images of the planet. Mars Express was mainly successful in that its orbiter with its instruments possibly detected liquid water. This was added onto findings of methane, which was another sign that there may be microbial life on Mars. Unfortunately, the rover the spacecraft carried, Beagle 2, failed to make contact after landing. It was later found that its solar panel did not open properly.

Meanwhile, NASA launched a mission to follow up on the success of the rover Sojourner. In January 2004, the rovers Spirit and Opportunity landed on the Red Planet. These robots acted as field geologists and using tools tested and analyzed rock all the while taking fantastic images of the landscape in full color. Their research began to paint a picture that arid Mars had a wet past. Amazingly, these pair of rovers lasted far beyond the anticipated 90 day mission. Spirit lasted for six years and had explored nearly 5 miles, while Opportunity lasted over 14 years and racked up 28 miles. NASA, it should be said, was very careful about sending the rovers too far abroad.

The increase in Martian exploration has made Mars the most well‐understood planet outside of Earth in our solar system. But questions still need to be answered, particularly if Mars had harbored life in its deep past, and if it has the potential to maintain life in the future. NASA's Curiosity rover seeks to help answer those questions. After touching down on the Red Planet in August 2012, this rover has been exploring the Gale crater gathering air, soil, and rock samples for analysis. To do this, Curiosity has an assortment of scientific tools, including a robotic arm, multiple cameras, a spectrometer, and lasers.

More advanced than Curiosity is the Perseverance rover, which landed on February 18, 2021, in the Jezero Crater. In its quest for microbial life, the rover carries seven instruments, including a device to test if oxygen can be produced from Martian carbon dioxide, ground‐penetrating radar, and a camera device that can detect the chemical composition of materials. Perseverance also has the capability to drill core samples and even package them in tubes for eventual retrieval. Remarkably, Perseverance also transported a miniature helicopter to Mars, named Ingenuity, as a technology demonstration. When the little drone took off on April 19, 2021, it was the first time powered flight took place on another world.