Forty years ago today, NASA launched the Viking 1 spacecraft to Mars, where it would become the first probe to successfully study the Martian surface. The touchdown was a major milestone in the exploration of Mars, providing the first images and data from the red planet, which had been obsessively studied from afar for centuries.
"The excitement was overwhelming!" said Viking mission director Tom Young in a 2006 retrospective of the landing. "People were hugging each other, jumping up and down—doing all those things you do when an extraordinary event has taken place."
Viking 1 went on to become one of the most productive landers ever deployed on Mars, operating for 2,307 days before it finally shut down on November 13, 1982. It held the record for the longest Martian surface mission for decades, until the Opportunity rover finally beat it out in 2010 (and that little trooper is still going, by the way).
Because it was the first lander to study Mars from the surface, practically everything Viking 1 did resulted in surprising discoveries. For example, apparently it was something of a public sensation when Viking images revealed that Mars's skies aren't blue.
The lander also widely sampled the planet's volcanic soil to learn its chemical composition, and rooted out evidence that rivers and lakes had once flowed at the landing site. It ran numerous tests to search for life, the results of which are still contested today. And it took lots of pictures—about 1,400.
Moreover, on a geopolitical level, NASA's success with Viking 1 was kind of like winning the Martian Triple Crown against the Soviet space program. Over the course of the 1960s and early 1970s, the USSR desperately tried to get a jump on NASA with regards to Mars exploration, and launched well over a dozen flyby, orbiter, and landing attempts.
These missions failed hard and often. Just check out the below table of the first attempted Mars encounters.
NASA, meanwhile, launched fewer spacecraft, but invested a lot more energy into its missions—a quality over quantity approach. In this way, they nabbed the first successful flyby of Mars with Mariner 4 in 1965, and followed it up with two more lucrative Mariner flybys in 1969.
In response, the Soviets gave up on Mars flybys altogether to focus on orbiters and landers instead. But there, too, they struggled, and NASA eventually secured the title for first successful Mars orbiter with Mariner 9 in 1971. The USSR was able to pull off the first hard landing (read: crash) on Mars the same year, but gave up on exploration of the planet after Viking 1 touched down.
Given how sophisticated the Soviets were in other areas, like Venusian exploration, it's strange that they simply could not get the hang of Mars missions.
Even weirder is the fact that the problem still persists. All four of Russia's attempts to visit Mars post-Viking have also failed, most recently the 2011 Phobos-Grunt mission. NASA, meanwhile, has been more or less nailing it with powerhouses like the Spirit and Opportunity rovers, the MAVEN orbiter, and Curiosity—the most sophisticated rover yet.
Fortunately, other nations are also pioneering their own Martian missions—most notably the European Union and India—so the future of the planet's exploration is already shaping up to be a lot more diverse.
But all of these missions stem from the success of Viking 1 (and its companion Viking 2), which gave humanity its first glimpse of the harsh, beautiful Martian landscape, and emboldened NASA to explore it more fully. Though the lander itself is long dead, its legacy as a pivotal early victory in Martian exploration is alive and well, 40 years on.
Correction: An earlier version of this story indicated that Viking 1 achieved the first soft-landing on Mars. It was actually the Soviet lander Mars 3 in 1971.