How long could a human being be kept in "suspended animation"?

Question

I read a report stating that it was still completely unkown how long we could keep a human being in suspended animation, but, in another book I read that any longer than 200-300 years would be completely impossible. Obviously we're talking about tomorrow's technology. In both cases they we're talking keeping astronauts in stasis on long term voyages, ie: interstellar travel.

Answer 1

I've often read about scientists wanting to freeze certain people to keep them alive until there is a cure for what caused their death, and I wondered what they would do if they discovered that the dead person had frozen to death.

Answer 2

As long as someone pays the bills.

What's the use, when everything you knew and cared about would be gone.

Answer 3

as of right now suspended animation is impossible.  you would end up freezing the subject and ultimately killing them.  tomorrow, who knows.  anything is possible.  one day we will have the technology to place someone in suspended animation.  but not today.

Answer 4

The common idea for "freezing" someone into suspended animation is impossible.  Flash-freezing someone would cause a LOT of cell damage, and would easily kill you.

The only *currently* known POSSIBILITY for suspended animation is by copying animals that hibernate.  Bears, for example, can survive the winter months with NO food by sloooooooowwwwinnnnnng down all their bodily functions...

...scientists believe that it may be possible for future astronauts to enter such a metabolic state as well.  We simply need to understand its mechanisms better.

Answer 5

Technically, bears don't hibernate:

http://en.wikipedia.org/wiki/Hibernation

It isn't know if slowing down metabolism through hibernation increases lifespan or not.  It would do little good to sleep for 50 years if you also aged 50 years.  

"Slow" manned interstellar space travel is a romantic notion but not likely to ever be practical.  The experience with the exploration of the solar system shows you get far more benefit using robotic probes than manned ones.