If Congress and federal agencies are smart, they will think about how to expand America's rocket industry, allowing more diversified high and low launches, working to help young companies get ahead, while not damaging the environment in the process.  One body of research suggests that the time to consider this is now.

A recently released study by one set of scholars suggests that rocket launches are having only minimal impact on the environment but that rapid growth of this sector – for all good and proper reasons, creating American jobs as rockets are built and launches proliferate inside the U.S. –  indicates advance thinking.

Says the study, "[C]oncerns about atmospheric rocket emissions are analogous to early recognition of space debris, which continues to be a policy challenge today."  Then the issue of fuels being used in these launches is discussed in depth. 

The big takeaway is that rocket fuel (an important aspect of rocket science) matters, and if Congress and federal agencies are smart, they will promote and contract more with companies capable of thinking ahead about the environment. 

In practical terms, this seems to mean favoring companies and research that get us away from solid fuels as well as methane and kerosene.  While lower-atmospheric impacts are objectively less, the stratosphere may be changed by these fuels.

Data and longer-term research remain sketchy, and some solid-fuel rocket companies may hide behind lack of specificity in scientists' long-term projections, but that is a bit like questioning whether a child will grow at all when you don't know with specificity how tall he will become.  Smart policy is to assume growth and then manage it.

In the case of rocket fuels, we do know a little.  We know, for example, that parallel problems, left unmanaged or ignored, have created major policy headaches.  Thus, as the researchers suggest, "debris accumulation in valuable orbits is widely acknowledged to present an existential risk to continuing space operations and industry growth," in part because we did not think ahead.

Likewise, picking rocket fuels, engines, and smaller companies that do not lean on solid rockets, which tend to be the biggest provocateurs of stratospheric change, could be wise, even prescient.  As the researchers indicate, dealing "decisively" with this problem in "formative stages" helps.  Thus, "if the potential magnitude of the space debris problem had been recognized early," it might not be "the significant risk we face today."

Likewise, choosing companies and options that tend to favor fuels that do not – from what we do know now – have any effect may be smarter for all.  As they report, "today, launch vehicle emissions present a distinctive echo of the space debris problem," as "rocket engine exhaust emitted into the stratosphere during ascent to orbit adversely impacts the global atmosphere." 

This is not speculative, but proven.  More to the point, "solid rocket motors inject chlorine directly into the ozone layer and chlorine has been subject to international regulation since 1987."  Moreover, "a second concern has come to light," tied to particle emissions from solids that affect solar energy. 

In short, solids are bad news in some ways, even if minimal for now and unclear how bad, since we do not know how "tall" the problem will grow.  Still, without being either hangdog doomsayers or Pollyannaish "sweep it under the rug" sorts, there is an answer.  Since a variety of rocket fuels, engines, and companies do not use solid rocket engines, methane, or kerosene, the right answer may be to be sensitive to the possible. 

In the context of gradually emerging research, federal government decision-makers – contracting agencies, Congress, and research arms – should be focused on favoring those fuels, engines, and options that do not depend on solids or the more noxious liquid fuels (specifically methane and kerosene), since doing so will help preserve the stratosphere unchanged and essentially amounts to wise policy. 

Thinking ahead is not always easy, but if Congress and federal agencies are smart, they will think about how to expand America's rocket industry – by informing, encouraging, and contracting with companies already thinking ahead, protecting the stratosphere with non-solid, non-methane, and non-kerosene launches.  Based on the latest research, that would be a win-win.  We need all those we can find.

Steven L. Mosteiro is a former strategic planner, policy analyst, and missile defense expert with the U.S. Office of Secretary of Defense and the Office of Secretary of the Air Force.