Another problem with longer flights

In any trip for humans beyond the moon (mars and beyond)
artificial gravity is a necessity.

Space.com reports:
[1]

quote
Astronauts that spend long months aboard the International Space Station
lose bone strength faster than previously thought and have a higher risk
of breaking their hips later in life, a new study reports.

A survey of 13 space station astronauts found that their bone strength
dipped by at least 14 percent on the average during their half-year
stays aboard the orbiting laboratory.

Three of the astronauts lost up to 30 percent of their bone strength
during their long-duration spaceflights, putting them on par with the
bone strength of older women with osteoporosis on Earth, the study
reported.
end quote

If in only 6 months trips they lose 14% of their bone strength,
in a trip of 2 years (the minimum time for a Mars trip) the strength
of their bones would disminish in such a measure that it would be a one
way trip only. They could not resist earth gravity when they come back.

This means that artificial gravity is a must for any trip that takes
more than 2-3 months. Note that the risk of breaking their bones much
later in life increases since apparently is very difficult to get
the lost strength back.

This is another big problem with humans in space and with human
spaceflight.

[1]
http://www.space.com/scienceastronom...ngth-loss.html
--
jacob navia
jacob at jacob point remcomp point fr
logiciels/informatique
http://www.cs.virginia.edu/~lcc-win32

On Jan 27, 7:02*am, jacob navia wrote:
In any trip for humans beyond the moon (mars and beyond)
artificial gravity is a necessity.

Space.com reports:
[1]

quote
Astronauts that spend long months aboard the International Space Station
lose bone strength faster than previously thought and have a higher risk
of breaking their hips later in life, a new study reports.

A survey of 13 space station astronauts found that their bone strength
dipped by at least 14 percent on the average during their half-year
stays aboard the orbiting laboratory.

Three of the astronauts lost up to 30 percent of their bone strength
during their long-duration spaceflights, putting them on par with the
bone strength of older women with osteoporosis on Earth, the study
reported.
end quote

If in only 6 months trips they lose 14% of their bone strength,
in a trip of 2 years (the minimum time for a Mars trip) the strength
of their bones would disminish in such a measure that it would be a one
way trip only. They could not resist earth gravity when they come back.

This means that artificial gravity is a must for any trip that takes
more than 2-3 months. Note that the risk of breaking their bones much
later in life increases since apparently is very difficult to get
the lost strength back.

This is another big problem with humans in space and with human
spaceflight.

[1]http://www.space.com/scienceastronomy/090126-astronauts-bone-strength....
--
jacob navia
jacob at jacob point remcomp point fr
logiciels/informatiquehttp://www.cs.virginia.edu/~lcc-win32

Why do you folks keep excluding cosmic and secondary/recoil radiation?

~ BG