The
history of current space vehicle technology is a one of
high expense and overuse of material. The first vehicles
put into space were orbital capsules. Although their size
was barely large enough to hold the astronauts who manned
them, the technology required to launch them off the ground
and into orbit was about 10 times the size of the actual
craft.
To achieve a Low Earth Orbit (LEO) - where a vehicle can
stay aloft—the first rocket left Earth in several
stages. The amount of fuel used to propel the rocket was
determined by the weight of the capsule and its payload,
the weight of the propellant rockets, and the weight of
the fuel itself before lift-off. A certain amount of the
rocket assembly is destroyed in the launch, and the remaining
parts burned up in the atmosphere once the capsule was delivered
to LEO. All that returned to Earth was the orbiting capsule
with its payload.
To put a satellite in orbit we must go much higher than
LEO to at least 250 miles above the Earth's surface. That
requires more fuel, thus more or bigger rockets.
As the United States decided to venture beyond Earth’s
orbit and head to the moon, the expense increased dramatically.
Not only did we need to propel a ship past LEO, but now
the ship needed to carry enough fuel to accelerate to the
moon, maintain an orbit for a specified time, then accelerate
out of moon orbit and return to Earth. The moment any vehicle
goes beyond LEO, it must carry within it the fuel needed
to complete its mission and return its payload. That increased
fuel meant an increased payload. This greatly added to the
weight the rockets had to launch. By the rocket principle
of propulsion, an increased payload requires a larger rocket.
Along with the increased size and weight of the rockets
came an increased fuel need, and … Well, the circle
continued, the costs increased exponentially, and still
only a fraction of the capital investment returned to Earth,
unable to be reused.
By 1981 the United States had developed a reusable craft
- NASA’s Space Shuttle. This vehicle, once propelled
into space, can carry fuel needed for its mission and its
return, and it has horizontal landing capabilities so that
it can return to space. However, the it still requires enormous
rockets - larger than the craft itself - to launch. With
an empty weight of about 63,000 pounds, and its accompanying
propellant rockets at about 4 million pounds, NASA’s
Space Shuttle costs about $10,000 per pound to complete
a mission.
NASA's Space Shuttle uses hundreds of tons of fuel every
time a launch occurs, and it must be rebuilt and refinanced
each time since the vast majority of capital goes into a
product which primarily gets burned up or otherwise becomes
unusable.
The present state of the art has reached a ceiling and prohibits
any commercial ventures.