Hibernating astronauts would need smaller spacecraft

phys.org ^ | November 18, 2019 | European Space Agency

[BenLurkin]

They took as their reference an existing mission study to send six humans to Mars and back in a five year timescale.

The study found the spacecraft mass could be reduced by a third by removing the crew quarters with a similar reduction in consumables, equivalent to several tons of saved mass. Hibernation would take place in small individual pods that would double as cabins while the crew are awake.

The assumption was that a drug would be administered to induce "torpor"—the term for the hibernating state. Like hibernating animals, the astronauts would be expected to acquire extra body fat in advance of torpor. Their soft-shell pods would be darkened and their temperature greatly reduced to cool their occupants during their projected 180-day Earth-Mars cruise.

Radiation exposure from high-energy particles is a key hazard of deep space travel, but because the hibernating crew will be spending so much time in their hibernation pods, then shielding—such as water containers—could be concentrated around them. And existing research into hibernation shows it gives enhanced radiation protection in its own right.

"For a while now hibernation has been proposed as a game-changing tool for human space travel," explains SciSpacE Team Leader Jennifer Ngo-Anh. "If we were able to reduce an astronaut's basic metabolic rate by 75% – similar to what we can observe in nature with large hibernating animals such as certain bears—we could end up with substantial mass and cost savings, making long-duration exploration missions more feasible.

"And the basic idea of putting astronauts into long-duration hibernation is actually not so crazy: a broadly comparable method has been tested and applied as therapy in critical care trauma patients and those due to undergo major surgeries for more than two decades."

[motor_racer]

After a long, motionless hibernation, their muscles would be so atrophied they wouldn’t be able to stand

[Pete from Shawnee Mission]

Sad to hear you are ill, glad to hear you are still here.
Life from a hospital bed is ugly and good to escape.

Next stop,endure winter, hang on till spring, exult in summer & fall, plant your trees, repeat process.

(Prayers for healing and fortitude and good friends!)

[Carl Vehse]

Would hibernation affect the astronauts’ pay scale?

[Carriage Hill]

Many thanks; appreciate your concern and prayers, FRiends.

[Carriage Hill]

Thank you, FRiend.

[mrsmith]

You’re an inspiration.
Hang in there, and best of luck to you.

[Tallguy]

Open the pod-bay doors, Hal...

[BobL]

I have a lot of CRAPPY things to say about the medical profession. The results they had with you ARE NOT in that category...glad you seem to have recovered!

[Carriage Hill]

I was one of the lucky ones. Had really good, cutting-edge drs and nurses, especially at PSU-Hershey. I back to about 90%, now. The heart disease they found - I had 5 stents installed - is what will kill me.

[minnesota_bound]

It may not work out well.

[Telepathic Intruder]

Some cold-blooded animals have natural antifreeze to prevent ice from forming at sub zero temperature. But it only works so far. Once water freezes, there is nothing to prevent crystallization which causes it to expand, destroying every cell in the body. It’s just the physics of how the water molecule works, and as Scotty would say you canna change the laws of physics. Walt Disney would love it if we could (he had his head cryonically frozen).

[Telepathic Intruder]

"Why can't we spend that money solving problems on earth before going into space"? A common question. My response:

Earth will always have problems, but we will never advance if we spend all our resources on present-day ones. Would we have solved any of our stone age problems by remaining in the stone age?

[dhs12345]

Can't get around the water issue. We are made mostly of water. However, maybe through some external means maybe we can prevent the water from “freezing” well below 0c. As an example: one way to do this is to add salt which changes it transition point.

Anyway, what is the goal here? The goal is to slow down the metabolism of a the human being for a very long period of time without damage or side effects. What is the minimal external supplied energy (heat, food, etc) to keep the bodily functions operating properly. Also, what about atrophy and bone density (especially in a low gravity environment).

Anyway, it seems like you might be able to apply an external EM source that might suspend the the water molecules thus preventing freezing crystalization.

[dhs12345]

Yes. But isn’t a deuterium reactor old technology?

Also, will the heavy water become radioactive if it is used in a reactor (for propulsion and powering the spaceship I presume).

You probably wouldn’t want it flowing near the astronauts.

[going hot]

Could be some alien race zoomed by earth a few 100 million years ago while venting their black water.

[Telepathic Intruder]

As I said, adding antifreeze can lower the actual freezing temperature of water. Eventually water must freeze, however. And when it does it forms a crystalline structure that is larger in volume than in the liquid state. Most substances shrink in size during solidification. Just about all metals, for example.

But what does freezing do to preserve something? Heat causes molecules to jiggle and drift around, eventually losing any of their original structure. So the colder the better. How cold can water get before freezing? Who knows. Without some extreme future or alien technology, not very far below 0 degrees Celsius.

[dhs12345]

The problem is “adding antifreeze” to a human body. Not a good thing, IMO.

By doing it externally by locking the water molecule into place with some form of radio waves. Maybe forcing the water molecules to align and be held in stasis while the temperature is lowered.

Something that penetrates the body without harm. One form of EM is an xray another is what happens in an MRI with a mag field. Both types interact with the human body and cells directly. Well maybe an xray is not a good example. A microwave is tuned to the water molecule and causes the molecule to jiggle randomly. How about a more organized, nonrandom molecular movement.

In other words, use some kind of EM source to prevent the water molecule from transitioning.

[Telepathic Intruder]

Like a Star Trek tractor beam? You might as well speculate about transporter technology. Pure science fiction.

[dhs12345]

No, more like the Star Trek transporter.

Definitely science fiction. However, science fiction can drive science fact and inspire ideas.

Is there warp drive? No, but is it an impossible idea? Yes, with current technologies and scientific understanding. In the future, IMHO no.

[dp0622]

Imagine if that was really it :)