In the middle of the 20th century, economist Robert Solow definitively established through his Nobel-Prize-winning research that improvements in technology are the primary contributor over time to increased output per capita — or productivity.

Previous NASA investments in space technology enabled the Apollo mission to the Moon and the development of a reusable space shuttle, as well as a series of well-documented spinoffs and benefits to the larger American economy. In the years prior to Apollo, 10 percent of the NASA budget was dedicated to space technology. In the years prior to space shuttle development, while Apollo was under execution, 5 percent of the NASA budget was still dedicated to space technology investments. Once the shuttle began development, NASA’s investment in space technology was squeezed down to 2 percent of the budget, where it has remained. The current budget will represent the smallest percent of the NASA budget dedicated to space technology in history. At the same time, NASA’s budget as a percent of the federal budget has decreased from 4 percent during Apollo to half of a percent now — once again, the lowest in NASA’s history. Hence the percent of space technology investment as a percent of the federal budget has decreased by an order of magnitude since the 1970s.

Because of this chronic underinvestment in space technology, we are retiring the space shuttle with nothing ready to replace it in the near future, and we are ill prepared for any human exploration beyond low Earth orbit (LEO) despite a consensus among Congress, NASA and the White House to pursue such exploration.

Without advances in space technology, NASA’s mission planners have estimated that a single human mission to Mars would require the equivalent of assembling 12 international space stations in Earth orbit and sending them on the trip. With proposed technology investments in cryogenic boil-off, aerocapture, advanced propulsion, in-situ resource utilization and closed-loop life support technologies, this number can be reduced by a factor of six.

Human explorers cannot spend any significant amount of time beyond LEO unless we improve radiation monitoring and protection technologies. Significant investments in research and development of advanced nuclear and/or solar propulsion systems are required to allow human explorers to travel to Mars and many near Earth objects for reasonable costs. To economically explore our solar system, we will need to invest in in-situ resource utilization technologies that allow us to “live off of the land” by using indigenous materials such as hydrogen and oxygen. Investments in nano-materials and nano-sensors will allow us to lower the mass and cost of exploration systems. Inflatable structures will allow us to save money by launching large in-space and planetary surface habitats in smaller volumes. The same principle holds true for the large aerodynamic decelerators we will need to land large payloads on the martian surface, and potentially for Earth entry as well. We will need space suits that last an order of magnitude longer than those of Apollo while being lighter and more flexible. Investments in long-term storage and transfer of cryogenic hydrogen, oxygen and methane will be required to efficiently use these important sources of fuel, power and life support.

We can spend billions of dollars on launch vehicles and capsules and endlessly argue about whether they should be government-developed and -owned or commercial, but without immediate investments in these space technologies, they will have nothing to launch and no place to go.

In addition to focused investments in space exploration technologies, a consensus has developed among the National Academies, Congress, NASA and the White House that there is a need for investments in space technology research that is not focused toward a particular near-term mission or system. Throughout most of its history, NASA has invested tens of millions of dollars annually in basic space technology and concepts research. Since the NASA Institute for Advanced Concepts (NIAC) was disbanded in 2007, the agency has provided no funding in this area. Historically, innovation often comes from allowing talented researchers time and funding to brainstorm and experiment with new concepts and technologies. Underinvestment in space technology research also can lead to NASA’s mortgaging its future in another way by not engaging and investing in the university students who will be future NASA innovators and explorers. A large percentage of early-stage space technology research is performed by universities and students, who are often inspired to work for NASA and the aerospace industry once engaged in challenging and interesting tasks.

Based on these observations, it would appear that NASA needs to immediately invest in a reinvigorated, balanced space technology program at a level of at least 5 percent of NASA’s budget. Fortunately, that is exactly what is proposed in the president’s 2012 budget under the new Office of Chief Technologist. Included are focused space technology investments in the areas mentioned above, and there is also funding for a new NIAC and space technology research grants and fellowships.

During last year’s budget negotiating season, a consensus was developed between the White House and both Houses of Congress to fund this new space technology program at the levels currently proposed. As we venture into this year’s budget negotiating season, we need to remember that “whatsoever a man soweth, that shall he also reap.” Are we going to adequately invest in the required technologies to allow a new generation of space explorers to go beyond Earth, or are we going to eat our seed corn, retire, sit on our porch and tell our grandchildren of all the great things we once did in space?

Robert Lindberg is president and executive director of the National Institute of Aerospace (NIA). Douglas Stanley, a principal research engineer at Georgia Tech, is in residence at NIA.