Return on investment (ROI) is defined as "a performance measure used to evaluate the efficiency of an investment or to compare the efficiency of a number of different investments." To calculate ROI, the return of an investment is divided by the cost of the investment. While we can calculate the costs, it is difficult to quantify the financial return of space exploration. Rather than a dollar figure, the return on space exploration is better expressed in terms of how it has benefited humanity.

NASA Spending
NASA spending has a tendency to overshadow NASA victories. Consider NASA's recent Curiosity mission. In early August, the Mars Science Laboratory mission (part of NASA's Mars Exploration Program) had a tremendous victory when it successfully landed the Curiosity rover on Mars. Over its 23-month mission, Curiosity will "investigate whether conditions have been favorable for microbial life and for preserving clues in the rocks about possible past life." Despite what we stand to learn from the mission, it has been viewed with much criticism because of its $2.5 billion price tag. In fact, much of the media attention surrounding this momentous achievement has been centered on the spending. The $2.5 billion, while significant, averages out to about $312 million each year over its eight-year mission. That's about $1 for every person in the U.S.

NASA's budget, which includes funding for science, exploration, aeronautics, space operations, space technology, education, cross agency support, construction, and environmental compliance and restoration, is the smallest budget of the major agencies in the federal government. NASA spending peaked with the final Gemini mission in 1966, three years before Apollo 11's Neil Armstrong stepped onto the Moon and said, "That's one small step for man, one giant leap for mankind."

Since its birth in 1958, NASA's yearly outlay as a share of total U.S. Federal outlay has consistently remained below 1%. Over the past five years, this figure has been closer to 0.5%. Dr. Neil deGrasse Tyson, astrophysicist and director of the Hayden Planetarium, once tweeted, "The U.S. bank bailout exceeded the half-century lifetime budget of NASA."

The Benefits of Space Exploration
Tyson was asked, "What has humanity gained from the billions of dollars that NASA has spent?" His response revealed the challenge in quantifying the merits of space exploration. "You imply that the question can be answered with a quote. That may be possible, but it took me a whole book (referring to his "2012 Space Chronicles: Facing the Ultimate Frontier") to address that question thoroughly," he said.

There is no easy answer that succinctly and completely explains the many ways in which space exploration has benefited mankind. In addition to fulfilling our innate desire to explore and understand our place in the Universe, some of our most important technological and scientific advancements have been inspired directly or indirectly by space technologies. Consider how your life, and all our society, has benefited from the following NASA-funded inventions:

  • Aircraft collision-avoidance systems
  • Cordless power tools
  • Corrosion resistant coatings for bridges
  • Digital imaging
  • Ear thermometers
  • GPS (global positioning satellites)
  • Household water filters
  • Hydroponic plant-growing systems
  • Implantable pacemakers
  • Infrared handheld cameras
  • Kidney dialysis machines
  • LASIK corrective eye surgery
  • Memory foam mattresses
  • Scratch-resistant sunglasses
  • Safety grooving on pavement
  • Shoe insoles
  • Virtual reality
  • Weather forecasting

Space exploration has also expanded human knowledge and contributed to research in education, healthcare, pollution control, rain forest protection and transportation. These and many other NASA-inspired advancements have a profound effect on life on Earth by improving health, safety, comfort and convenience. Entire industries have been built on space technology, including personal computers and natural resource mapping. As one of the nation's strongest industries and an employer of nearly one million Americans, the aeronautics industry uses NASA-developed technology on nearly all aircrafts.

Without NASA's motivation to make discoveries and invent new technologies in its mission to explore space, many of these auxiliary benefits may have been years or decades away. They perhaps may never have even come to fruition.

The Bottom Line
Despite the fact that one cannot put a dollar figure on the benefits of space exploration, countless advancements in science and technology can be attributed to the exploration of space. As Tyson says, if all technologies that were influenced by space innovations were removed from our homes we would be in "a newly barren existence in a state of untenable technological poverty, with bad eyesight to boot, while getting rained on without an umbrella because of not knowing the satellite-informed weather forecast for that day."