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PHYSICS DF THE IMPOSSIBLE
Station, for example, will require upwards of one hundred launches of
shuttle missions for complete assembly and costs have escalated to
$100 billion. It is the most expensive scientific project in history. Building an interstellar space sail or ramjet scoop in outer space would cost
many times that amount.
But as science fiction writer Robert Heinlein was fond of saying, if
you can make it to 160 kilometers above the Earth, you are halfway to
anywhere in the solar system. That is because the first 160 kilometers
of any launch, when the rocket is struggling to escape the Earth's gravity, cost by far the most. After that a rocket ship can almost coast to
Pluto and beyond.
One way to reduce costs drastically in the future would be to develop a space elevator. The idea of climbing a rope to heaven is an old
one, for example, as in the fairy tale "Jack and the Beanstalk," but it
might become a reality if the rope could be sent far into space. Then
the centrifugal force of the Earth's rotation would be enough to nullify
the force of gravity, so the rope would never fall. The rope would magically rise vertically into the air and disappear into the clouds. (Think
of a ball spinning on a string. The ball seems to defy gravity, because
the centrifugal force pushes it away from the center of rotation. In the
same way, a very long rope would be suspended in air because of the
spinning of the Earth.) Nothing would be needed to hold up the rope
except the spin of the Earth. A person could theoretically climb the
rope and ascend into space. We sometimes give the undergraduates
taking physics courses at City University of New York the problem of
calculating the tension on such a rope. It is easy to show that the tension on the rope would be enough to snap even a steel cable, which is
why building a space elevator has long been considered to be impossible.
The first scientist to seriously study the space elevator was Russian
visionary scientist Ronstantin Tsiolkovsky. In 1895, inspired by the Eiffel Tower, he envisioned a tower that would ascend into space, connecting the Earth to a "celestial castle" in space. It would be built
bottom-up, starting on Earth, and engineers would slowly extend the
space elevator to the heavens.
PHYSICS DF THE IMPOSSIBLE
Station, for example, will require upwards of one hundred launches of
shuttle missions for complete assembly and costs have escalated to
$100 billion. It is the most expensive scientific project in history. Building an interstellar space sail or ramjet scoop in outer space would cost
many times that amount.
But as science fiction writer Robert Heinlein was fond of saying, if
you can make it to 160 kilometers above the Earth, you are halfway to
anywhere in the solar system. That is because the first 160 kilometers
of any launch, when the rocket is struggling to escape the Earth's gravity, cost by far the most. After that a rocket ship can almost coast to
Pluto and beyond.
One way to reduce costs drastically in the future would be to develop a space elevator. The idea of climbing a rope to heaven is an old
one, for example, as in the fairy tale "Jack and the Beanstalk," but it
might become a reality if the rope could be sent far into space. Then
the centrifugal force of the Earth's rotation would be enough to nullify
the force of gravity, so the rope would never fall. The rope would magically rise vertically into the air and disappear into the clouds. (Think
of a ball spinning on a string. The ball seems to defy gravity, because
the centrifugal force pushes it away from the center of rotation. In the
same way, a very long rope would be suspended in air because of the
spinning of the Earth.) Nothing would be needed to hold up the rope
except the spin of the Earth. A person could theoretically climb the
rope and ascend into space. We sometimes give the undergraduates
taking physics courses at City University of New York the problem of
calculating the tension on such a rope. It is easy to show that the tension on the rope would be enough to snap even a steel cable, which is
why building a space elevator has long been considered to be impossible.
The first scientist to seriously study the space elevator was Russian
visionary scientist Ronstantin Tsiolkovsky. In 1895, inspired by the Eiffel Tower, he envisioned a tower that would ascend into space, connecting the Earth to a "celestial castle" in space. It would be built
bottom-up, starting on Earth, and engineers would slowly extend the
space elevator to the heavens.