
The rivalry between two billionaires is reducing the cost of space travel - artsandsci
https://www.1843magazine.com/technology/rocket-men
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JPLeRouzic
There is something strange about using chemical rockets to go to space. The
"rocket equation" tells that we need an ejection speed in the range of 4500
m/sec (ISP ~450) to reach a Low Earth Orbit (a few hundred kilometers). What
is strange is that it is not a question of energy, but only of ejection speed.

With chemical rockets we are near the upper limit of what can be done, both
theoretically and pratically. A rocket engine nearly melts after running a few
minutes. And as it runs at the edges of technologies and physics limits, it is
highly costly and unsecure.

What about inventing new designs? Why could not we use the energy stored in
tanks to run a large ion thruster? There are many heat-to-electricity schemes
that already used in space hardware!

