Mission Mars – Mission Improbable ?

A manned spaceflight to the planet Mars would have to overcome many obstacles- apart from the financial costs.
The cosmic radiation that would penetrate the astronauts cannot be shielded off sufficiently.It might cause cancer and/or weaken the immune system.
The weightlessness would weaken the bodies´ bones, including the bone marrow which produces the blood cells, and it would weaken the muscles.
It is obvious that putting two or more men or women into a small spaceship for three years or more almost without any privacy would create huge psychological
problems with sexuality, aggression and so on. The astronauts would have to collect their urine and their feces in order to recycle the water from it,
and they would have to live in a relatively small space where body odours and oily smell from the machines could not be cleaned sufficiently out of the air they have to breathe.
If they had a window in their spaceship the sky would look pitch dark as they get further away from the sun, if they had no window, they would see artificial light and nothing else for some years.
The useful scientific results of a manned mission to Mars will be very limited, and nobody knows how expensive such an endeavour would be-probably very very expensive.
It is more reasonable to spend NASA´s money for telescopes for outer space or for detectors for gravity waves or other things. Some scientists suggest building an observatory on the moon,
some suggest detecting electromagnetic waves in the wavelength of about one mile (ca. 1.6 kilometers) or more from a lunar observatory.That would also cost a lot,
but it might teach us interesting facts about the universe and its origin and its future.