Fifty years ago, NASA achieved one of its most significant robotic spaceflight milestones with the landing of the Viking 1 spacecraft on Mars. Marking the first fully successful landing on the Red Planet following the Soviet Union’s brief Mars 3 transmission in 1971, the mission deployed a suite of scientific instruments seeking evidence of life, the results of which continue to be debated.
Reflecting on the 1970s Viking Legacy and Future Mars Missions
While hailed as a crowning achievement of NASA’s initial Mars exploration program, the Viking missions were followed by a stark reality: Viking was the last NASA Mars mission for an entire generation. The subsequent lander, Mars Pathfinder, did not touch down until July 1997—almost exactly 21 years after Viking 1.
Today, members of the Mars science community worry that NASA faces a similar threat of another long gap in Red Planet exploration. The cancellation of Mars Sample Return (MSR) has placed the future of Mars exploration into question as the agency increasingly shifts its focus toward the Moon. Although the Perseverance rover continues to collect samples, uncertainty remains regarding when or if those samples will ever be returned to Earth.
Evaluating Costs, Flagship Missions, and Commercial Partnerships
The financial scale of historic missions and modern initiatives remains a central debate for planetary scientists. Viking stands as one of NASA’s most expensive science missions, carrying a present-day cost of $8.6 billion according to a Planetary Society assessment. This puts its price tag directly in line with Mars Sample Return, which carried cost estimates ranging between $8 billion and $11 billion before NASA attempted to restructure the program.
Both Viking and MSR shared profiles of being challenging, high-risk, and exceptionally expensive. Ultimately, NASA lacked confidence in MSR or disagreed on its importance enough to discontinue it, mirroring how the success of Viking came at the expense of a two-decade mission gap.
Looking forward, NASA is involved with up to four missions heading to Mars in 2028, though none represent conventional NASA-led science missions. These include the European Space Agency’s Rosalind Franklin rover featuring modest NASA participation (including the launch), the Mars Telecommunications Network communications spacecraft carrying a small science payload, and SR-1 Freedom—primarily a nuclear propulsion demonstration paired with SkyFall, a set of small Mars helicopters. Additionally, NASA announced plans to provide a science payload for an unnamed Mars mission developed by Relativity Space, though plans past 2028 remain unclear.
To sustain future exploration without crippling budgets, NASA has discussed commercial partnerships for future Mars missions analogous to the Commercial Lunar Payload Services (CLPS) program, though no awards have been made. Planetary scientist Jim Bell of Arizona State University noted that while amazing science can be accomplished with CLPS-scale or other small missions, decadal surveys outline questions that still require flagship missions. Furthermore, the high cost of the SR-1 Freedom project—estimated at over $2 billion—threatens to draw funds away from other planned Mars missions.
