Re: Space Travel by Humans is Possible

On Jan 20, 8:14 am, Einar <eina...@xxxxxxxxx> wrote:

You can´t solve it with reaction mass. It´s not the Moon. If Mars
would be like the Moon, i.e. airless, that solution would work. But as
Mars has got athmosphere, but rather too thin, landing like on the
Moon wont work.

There are two reasons why using rockets to land on Mars is difficult.

One is that Mars is larger, with more gravity, so more fuel is
required.

The other is that, due to Mars' atmosphere, damaging turbulence
effects will take place if an attempt is made to use *large* rocket
nozzles to brake the flight of a fast-moving spaceship.

And because Mars' atmosphere is very thin, using Mars' atmosphere to
reduce the spaceship's velocity enough to allow for a safe landing is
also difficult.

One way this can be dealt with is: a) to bring the extra fuel
required, and b) to use many small rocket nozzles instead of a few
large ones.

So we do know a *way* to land on Mars. Viking, for example, landed
under rocket power, instead of using the bouncing-airbags technique of
Sojourner that would be unsuitable for landing humans. (Incidentally,
the Viking lander weighed significantly more than a human being, so
using rocket fuel to land a Mercury-sized capsule with an astronaut on
Mars, while supplies and a habitat had previously been landed by the
bouncing Sojourner method seems entirely feasible.)

John Savard
.

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