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Astronauts that hibernate on long spaceflights is not just for sci-fi.
We could test it in 10 years.
By Tereza Pultarova published about 12 hours ago
"We need to fine tune everything before we can apply it to humans. But I
would say that 10 years is a realistic timeline."

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In science-fiction movies, astronauts have been hibernating for decades.
In science-fiction movies, astronauts frequently cross vast distances
while hibernating. (Image credit: 20th Century Fox, Aliens)
The first hibernation studies with human subjects could be feasible
within a decade, a European Space Agency (ESA) researcher thinks.

Such experiments would pave the way for a science-fiction-like approach
to long-duration space missions that would see crew members placed into
protective slumber for weeks or months on their way to distant
destinations.

Hibernating on a year-long trip to Mars would not just prevent boredom
in a tiny space capsule; it would also save mission cost, as the
hibernating crew members wouldn't need to eat or drink and would even
require far less oxygen than those awake. There are other, rather odd
benefits of hibernation, as well. Research in animals suggests that
bodies of hibernating astronauts might waste away much less than the
bodies of those awake in microgravity. Upon arrival, these hibernators
would thus be fit and ready to commence challenging exploration almost
straight away after regaining consciousness.

Related: NASA astronauts could hibernate on deep space missions thanks
to arctic squirrels

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For all these reasons, hibernation, also known as torpor, has long been
a staple of sci-fi space movies. From "Alien" to "2001: A Space
Odyssey," fictional space travelers have crossed vast distances cocooned
unconscious inside high-tech pods while AI machines and android robots
keep their spacecraft on a steady course.

Despite being a sci-fi trope, putting humans into long-term induced
torpor may not be a far-fetched idea after all. Jennifer Ngo-Anh, a
research and payload coordinator of Human and Robotic Exploration at ESA
and a co-author of a recent paper(opens in new tab) outlining the space
agency's approach to hibernation research, told Space.com that depending
on funding availability, the first human torpor trials could take place
as early as the mid-2030s.

"Of course, we need to finetune everything before we can apply it to
humans. But I would say that 10 years is a realistic timeline," Ngo-Anh
said.

This fine-tuning is already underway. First studies have shown that it's
possible to induce torpor(opens in new tab) in otherwise non-hibernating
animals, such as rats, and bring them safely back to life a few days
later. The process of triggering hibernation is rather intricate and
involves reduced exposure to daylight and a period of intense feeding
followed by a strict fast.

"The rats receive a drug, a neurotransmitter substance, and are brought
into a dark space with reduced temperature," Jürgen Bereiter-Hahn,
professor emeritus in neuroscience and cell biology at Goethe University
in Frankfurt, Germany, and member of ESA's hibernation research group,
told Space.com in an interview. "It works very nicely, but the problem
is that you have to apply the signaling molecule repeatedly to maintain
the state. You need to maintain very high levels of the neurotransmitter
and that could have deleterious effects over the longer term."

Why do we want to make people hibernate?
The question is whether induced torpor could ever be safe enough to be
administered to space travelers in tiny spacecraft with minimal medical
supervision and equipment. Ngo-Anh sees the problem from a different
perspective. Torpor, she said, could, in fact, be the only way forward
for long-duration space missions.

Loss of bone and muscle mass is a big issue for spacefarers. Even at the
International Space Station, where high-tech fitness machines are
available and strict exercise protocols are followed, astronauts lose up
to 20% of their muscle mass(opens in new tab) in a month. Their bones
get gradually weaker too. Footage of crews returning to Earth frequently
shows fragile beings transported by medical personnel in wheelchairs and
stretchers. But there will be no support crews waiting by after a
landing on Mars.

"This is a real problem for astronauts in microgravity," Bereiter-Hahn
said. "Astronauts need to train a lot because otherwise they really
would have serious problems when they get back to gravity conditions."

Research shows that the effects of microgravity on the human body
resemble those of long-term bed rest. Strangely, bed rest while
hibernating doesn't seem to result in such effects at all. Unlike a
patient recovering from a long illness or medical coma, an animal waking
up from hibernation shows surprisingly high fitness levels.

"When animals wake up from hibernation, they very quickly remember their
surroundings," Ngo-Anh said. "Within seconds, they remember where they
hid their food before they went into hibernation, and they actually
don't suffer much muscle loss, which is quite surprising after months
just lying and sleeping in a cave."

Researchers think that the key to the protective effects of the torpor
state is its physiology. Although hibernation superficially resembles
sleep, inside the body the process works in a completely different way.
Unlike a sleeping brain, a hibernating brain produces barely any
electromagnetic activity. The heart rate of an animal in torpor drops to
only a few beats per minute, and its body temperature declines to what
would otherwise be considered dangerous hypothermia. Even the cells that
make up the animal's body stop their usual business of processing or
creating nutrients, dividing and dying. By all biological measures, the
torpor state is almost like hitting a pause button on life.

"We know from studies that it reduces the lifespan of animals which
normally go into torpor when they are prevented from going into torpor,"
Alexander Choukèr, a professor of medicine and an anesthesiology expert
at the Ludwig Maximilians University in Munich, Germany, who is also a
member of the ESA team, told Space.com. "When they have these torpor
phases in between, the animals can live five years, for example. When
the torpor is missing, it could be just four years."

This pause-button quality of the torpor state is key to its promise for
spaceflight missions. The hibernating astronaut in a Mars-bound capsule
would not only save the agency cost for water, food and oxygen. He or
she would, most likely, wake up rather fit, without suffering many of
the negative side effects of long-term bed-rest or living in
microgravity. In fact, studies show that the slowed down cells of a
hibernating body don't get damaged by radiation, which is one of the
biggest health-concerns during lung-duration space missions.

Boon to medicine
These protective properties make hibernation a fascinating possibility
not just for spaceflight, but also for medicine. Just like astronauts in
microgravity, patients in long-term bed-rest and those in
medically-induced coma waste away quickly. The recovery is slow and
painstaking.

"We put people under anesthesia all the time, but they still degrade,"
said Choukèr. "After you leave an Intensive Care Unit, if you are there
for a long time, you are like a skeleton because of the degradation
metabolism that sets in. To be able to hit that pause button would be a
game-changer."

Slowing life processes, including the degradatory ones, to a minimum
would provide what Bereiter-Hahn calls a "bridge," a period of time that
would allow physicians to look for solutions without racing against the
clock.

"You can use that time to, for instance, develop special antibodies for
a tumor and treat that tumor very successfully," said Bereiter-Hahn.
"Also in organ transplantation, you would put the whole organ into
torpor, as well as the patient, and then you could exchange those organs
at much less danger for the patient."

In fact, added Ngo-Anh, cooling has been used by brain and cardiac
surgeons for decades to improve outcomes of complicated surgeries.

Although most of the current hibernation research is funded by space
agencies and zoology institutions, Choukèr thinks that the first human
to be put into this paused state of being will most likely be an
intensive care patient. Once the first human survives and benefits from
torpor, things will likely start moving forward much faster.

RELATED STORIES:
— Astronauts on Mars missions could suffer cognitive and emotional
problems, new research suggests
— Boiling blood and radiation: 5 ways mars can kill
— What does space do to the human body? 29 studies investigate the
effects of exploration

On 21.03.23 23:38, a425couple wrote:
> from
> https://www.space.com/astronaut-hibernation-trials-possible-in-decade
>
> Astronauts that hibernate on long spaceflights is not just for sci-fi.

It would kill any human being promptly.

a425couple wrote on 22/3/23 9:38 am:
> from
> https://www.space.com/astronaut-hibernation-trials-possible-in-decade
>
> Astronauts that hibernate on long spaceflights is not just for sci-fi.
> We could test it in 10 years.

So still Sci-fi .... at this time!!
--
Daniel