Exploring the Unknown - NASA's History Office

In many religions the wealth of the church is thought of as a common resource for its
members to help those in difficulties and sometimes, even when some members are successful,
to be used to facilitate additional success. To the extent that space colonies, in
addition to their religious connotation, might look like profitable ventures then the
investments would eventually increase the wealth of the church. Furthermore, through
merit criteria or lotteries, every member would have a chance to become a colonist, or a
tourist. The church might deem the high costs well worth the increased faith and activity
of its members—particularly if these “tourists” returned with an inspired and zealous commitment
to the church.
E. Potential for Growth
EXPLORING THE UNKNOWN 487
Our very rough estimate of current world space project expenditures is about $9 billion
per year on non-military developments and perhaps half that much on military space
programs. That is, total expenditures on space projects are about .2 percent of the GWP
(about .13 percent non-military, and .07 percent military).
In a pessimistic space scenario that small (.13 percent) fraction generally remains stable
or decreases, despite the fact that the cost of transportation to space must almost certainly
fall by more than a factor [271] of 10 during the next century. Still the GWP during
the next 100 years is expected—in our earth-centered surprise-free projections—to rise by
about a factor of 20. . . . If space expenditures merely keep pace with GWP they would be
approximately $200–$300 billion by then and would almost double again in the following
100-year period. The “truly” pessimistic space scenario would, on average, maintain a slower
growth in space investments than the GWP. On average means that “temporary” fluctuations
may vary that projection somewhat over periods of a few decades or less.
A moderate scenario, in our view, would, on average, but probably with erratic fluctuations,
show a growth rate in space which exceeds that on earth—perhaps by about a
factor of 2 or 3. Thus, the world’s space budget would have a mean growth rate of 3-1/2
percent to 5 percent, which would lead to space budgets between $200 and $1,200 billion
at the Tricentennial. We arrived at $700 billion for our particular Moderate Scenario
(Chapter VI).
However, we notice that the 2076 budget (or annual investment) estimate is extremely
sensitive to the assumed average growth rate. Over a hundred years a 2-percent change
in this average affects the budget by about a factor of 7—and, over 200 years, by a factor
of 50. Yet it appears to us that the inherent uncertainty in the average future growth rate
is intrinsically greater than 2 percent and may be as high as 5 percent—the latter leads to
a factor of more than 100 over a century and more than an astonishing 10,000 over two
centuries!
[272] On the positive side—that is, from a space enthusiast’s point of view—the high
growth rates lead to an optimistic scenario. In the Optimistic Scenario of Chapter IV the
average growth rate in worldwide space investments rose during the last quarter of the
20th century at about 10 percent per annum (about the average for a “glamour” or high
technology industry currently). During the first 100 years after a brief rise to a 12-percent
growth rate, the Gross Space Product (GSP) then declined steadily to about an 8-percent
growth rate, and during the second 100 years to 5 percent. . . . We note that the growth
rate in space, per capita, ends at about 2-1/2 percent—actually, less than the productivity
increase of the average American worker in recent decades. Thus, the Optimistic Scenario
portrayed would not be perceived as having an astonishing growth during any year of its
history—except perhaps during 1980–2000, when a general change in societal attitudes
toward space is assumed to occur. After the turn of the century it is just the assumed longterm
steadiness of the slowly declining growth rate that brings about a “miraculous” transformation—first
to a $30 trillion GSP and then, during the much slower growth of the