Why should we engage in manned space flight? Many people argue that
it is expensive and dangerous with little return.
This is not an argument for the space shuttle. It can be plausibly
argued that with manned and unmanned single-use rockets, we could have
achieved everything the space shuttle has achieved for cheaper. This
is an argument for why we should push manned space flight.
First I will give counterarguments, then arguments.
- Danger. The first thing to note is that "dangerous" is of little
importance while we have volunteers. At the moment, the number of
people willing to engage in space flight exceeds the number of people
able to engage in space flight by at least an order of magnitude.
- Expense. Manned space flight is very expensive right now.
Contrary to some beliefs, this is not inherent to the process
of manned space flight. So far, the expensive part of manned space
flight is not the weight of astronauts and the equipment necessary to
keep them alive. The expensive part is the design requirement of
capability to return to earth. However, this design requirement is
not inherently expensive because it implies the possibility of a fully
reusable system. As a reusable system, the space shuttle is a
failure, but this does not imply that all reusable systems are
failures. There have been many designs by many people which could
plausibly be engineered into a fully reusable system. It is also
somewhat obvious that expense can be dramatically reduced when you
realize that fuel costs are a small fraction of the current cost of
- Little return. What is meant by little return is "little return
for the money invested". Since manned space flight is not inherently
expensive, as it has been so far, the rate of return on the investment
in space flight could dramatically change, given a cheaper system.
Now, why should we engage in manned space flight?
- Motivation. Like it or not, we live in a world where people are
motivated by manned space flight. If we remove this motivation, less
will be accomplished because people will be less motivated. It is
difficult to measure the dollar-worth of motivation, but it is
significant. Without manned space flight as a goal, I would expect
NASAs budget to be cut by a large fraction.
- Research. Little in the way of space-based research has yet been
accomplished, but that is quite possibly due to the extremely limited
times and resources available in space. With a large number of
researchers with proper equipment in space for a year or two each, I
expect that significant research can and will be done. If nothing
else, studying the behavior of materials in space should be a lot
easier than on the earth. In addition, there is some hope that new
materials can be made in space.
- War. We have never had war in space, but if war comes, it would
be nice to have the upper hand. One important question is: are humans
helpful to war in space? The answer at the moment is possibly yes.
Currently computers have a very limited ability to plan and cope with
unforeseen events. They will cease functioning if they fall out of
communication and they are possibly even prone to subversion. Humans
are much more adept at coping with unforeseen and inimical conditions.
- Applications. If manned space flight can be made routine, cheap,
and easy, suborbital flights might become routine cheap and easy. How
much would you pay for a ticket to Australia on a one hour flight?
There is almost certainly a large market for suborbital flights, if we
can make the cost and danger sufficiently minimal.
- Capability. There is some difficult to assess value inherent in
having a capability. The ability to send men into space is inherently
valuable, just like any other capability. Some unforeseen problem
might arise requiring men in space. While this value is difficult to
assess, it should not be ignored.