MISSION FOR SLS
by Edward Hujsak
Now may be a propitious time to raise the question: Is it better to undertake an occasional
manned mission, at a cost of many billions of dollars, to explore asteroids, return to the moon,
and journey to Mars, or should we stay close to the planet and exploit a region that has so far been
only touched upon, despite the availability of the hugely expensive but sparsely manned Interna-
tional Space Station. An April 22 column by Washington Post’s Dana Milbank, titled “NASA’s
lofty goal of a manned Mars mission doesn’t match budget reality,” and subsequently printed in
other newspapers under the title: “Lost in Space,” underscores the confusion concerning the future.
There are two dominant scenarios, admitted;y with variations in each:
1. Occasional high dollar ventures by astronauts to destinations like asteroids, Mars and the moon.
For the most part, these are long, dangerous journeys, unlikely, however to sustain public interest
for long, until the destination is reached and then there is a short spurt of heart-stopping activity. (missions to Mars generate wide interest only after the spacecraft has landed).Then, the long
journey home. This scenario calls for infrequent SLS launches which will therefore be very high
cost, and result in exploring space at a snail’s pace. The United States is arguably the leader in
undertaking such missions, having already sent astronauts to the moon several decades ago. But it
is also the leader in robotic missions, even to the distant planets. A four decade hiatus has followed
the last exploratory manned mission: Apollo. Will another such hiatus follow a manned mission
to Mars?
2,The second scenario envisions a robust activity along several lines in low Earth orbit, quite within existing capability and for which the pattern has already been set by the Soviet Union’s Mir and
the United States’ Skylab, follow-on to Apollo. Instead of monster structures like the International
Space Station, what is envisioned are turnkey stations mirroring Skylab, of a size that can be lifted
into orbit by single flights of the SLS....around seventy-five metric tons.
It is a fair assumption that many nations in the world would like independent access to a
turnkey station, through lease or actual purchase, as well as transportation to and from. A part of
it may simply be prestige, but more likely it would be independent research by its own scientists
who need the space environment to proceed. These activities may range from medical research to
fundamental materials research and development, particularly in the nano region, a relatively new
frontier. A second application that caters to frivolous but adventurous tastes is tourist hotels. For
some, and there are many who can afford it, a week in earth orbit would be the adventure of a
lifetime.
The new paradigm envisions a bustling near-Earth activity, with perhaps hundreds of people in orbit doing valuable work in multiple stations, and at the same time proceeding with robotic
exploration of the outer regions, which is being done now with spectacular success. It foretells
major new industries.....design and construction of work stations, design, development and implementation of a reusable transportation system for economical transfer of personnel, and a system
for control, monitoring and servicing of stations as they age in service. It brings into focus the
challenge of operating in low Earth orbit with positive return on investment, as we do at geosynchronous orbit.
This is the only plausible scenario that will ensure a requirement for SLS flights at a reasonable rate. For other proposed missions, flights will be few and far between.......possibly years
apart. Thus they will be very expensive if one factors in the cost of keeping a launch crew and
production in place.
The United States is not the only nation that can undertake this unique opportunity. Russia
can certainly do it, and one wonders to what purpose they would be undertaking development of an
HLLV, with a seventy-five metric ton payload capacity, as recently announced. China too, a recent
newcomer, with no presence at the International Space Station, has already a demonstrated ability
with its own station and is capable of huge surprises.
In summary, this is one way to keep a vibrant space program in place, with inherent drivers to develop a reusable passenger transportation system, vastly improved situation for beneficial
discoveries, improved cooperation among nations and an enormous new employment base for
technological talent that presently lies dormant, risking loss of skills in an extremely valuable
area.
Mars and asteroids can wait. If we take the route of missions spaced decades apart, of
which there may be just one-of, there will exist little reason for the next generation to look to space
as a career opportunity.
