(CNN)
-- Want to ride an elevator into space? While the idea has been around for more
than 100 years, a breakthrough in nanotechnology could mean we
will be riding into space on a cable made of diamonds.
Scientists
at Penn State University in the US released a research paper last month that showed the way forward to
producing ultra-thin "diamond nanothreads" that have a strength and
stiffness greater than that of today's strongest nanotubes and polymers.
John
Badding, professor of chemistry at Penn State University, told CNN his team had
made the breakthrough while examining the properties of benzene molecules and
that it took 18 months of study to make sense of what the team had been seeing.
"It
is as if an incredible jeweler has strung together the smallest possible
diamonds into a long miniature necklace," Badding said. "Because this
thread is diamond at heart, we expect that it will prove to be extraordinarily
stiff, extraordinarily strong, and extraordinarily useful."
Benzene breakthrough
"What we found was that because our experiment
compressed the benzene much more slowly than had been done before, these new
materials formed," he said.
"Everybody thought that the benzene molecules would
link together in a way that was very disorganized, like a glassy amorphous
material.
"Instead,
what caught our attention was that our experiments told us there was order in
the benzene and that was the shock," he said.
That
all this occurred at room temperature was a further shock to the research team.
Under
pressure
He
said the scientists worked to test the hypothesis that when benzene molecules
break under high pressure, their atoms want to grab onto something else but
can't because the pressure removes the space between them.
"This
benzene then becomes highly reactive so that, when we release the pressure very
slowly, an orderly polymerization reaction happens that forms the diamond-core
nanothread," he said.
What
results is a material that is the strongest and stiffest known to science, but
is also very lightweight.
"One
of our wildest dreams for the nanomaterials we are developing is that they
could be used to make the super-strong, lightweight cables that would make
possible the construction of a "space elevator" which so far has
existed only as a science-fiction idea," Badding said.
Next
stop... outer space
The
Japanese construction company Obayashi is already investigating the feasibility
of a space elevator, envisioning a space station tethered to the equator by a
96,000km cable made of carbon nanotechnology.
The
space station would orbit the earth in a geostationary position with the cable
held taut through the centrifugal force of the earth's rotation - in much the
same a hammer thrower spins the hammer at the Olympics.
Robotic
cars with magnetic motors would take seven days to reach the space station,
lifting cargoes and people into space at a fraction of the current cost.
According
to the International Space
Elevator Consortium (ISEC), space payloads would cost in the order of just
hundreds of dollars per kilogram rather than the current $20,000 a kilogram
that rocket technology costs.
The
key is in the small scale
At
the core of the project is the nanotechnology that would make cables from a
material harder and stronger than any currently found on Earth.
A
2.5-inch thick cable made from carbon nanotechnology could lift the equivalent
of three International Space Stations per day into orbit, according to ISEC.
"The
tensile strength is almost a hundred times stronger than steel cables so it's
possible," Yoji Ishikawa, a research and development manager at Obayashi
told the Australian Broadcasting Corporation.
"Right
now we can't make the cable long enough. We can only make 3-centimeter-long
nanotubes, but we need much more ... we think by 2030 we'll be able to do
it."
Goodbye,
rocket man
A
space elevator is not the only non-rocket technology being investigated as a
means of getting man-made objects into space.
In
the past NASA has examined everything from high-velocity artillery to
rail-launched maglev projects as a way of getting objects into space.
Physicist
Stanley Starr of NASA's Kennedy Space Center said for the time being, NASA's
emphasis is on developing exploration technologies to be used once a craft is
already in space.
"And
there are many challenges in that area," Starr told CNN.
Nevertheless,
the space agency continues to look at systems -- some of them quite bizarre
such as the Slingatron -- that could achieve orbit without the use of
fuel-hungry rocket systems.
"The
space elevator is an interesting concept but will require a breakthrough in
materials or the addition of a totally new concept to make it work. I don't
foresee space elevator working in my lifetime," Starr said.
"I
briefly looked at the Slingatron concept and don't believe it is
feasible."
When
physics gets in the way
Certain
problems of aerodynamics and physics, he said, persist despite technological
advances. While some concepts that use high velocities -- such as super
artillery -- can work, balancing the greater aerodynamic forces with problems
of heating remain.
"For
example if you directly launch a small satellite out of a cannon with enough
velocity to reach orbit, the projectile will probably be destroyed by the heat
and stress," he said. "If not, most of your mass is devoted to the
structure and not much to the working payload."
Even
so, he said NASA has not abandoned the idea of a non-rocket launch.
"I
believe NASA will eventually invest in advanced non-rocket launch technology,
but I don't think it will be very soon," Starr said.
"I
would like to NASA establish a group, preferably networked from a number of
NASA centers, that is actively looking new launch technologies and making
recommendations for new investigations."
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