Comments on: Hibernation research for long space flights

By: pzatchok

pzatchok — Sun, 30 Apr 2017 19:08:23 +0000

Hibernation instead of staying awake saves NOTHING for a Mars mission.
Flight time is too short.
You sleep through the trip to save food and water/oxygen.

So to save a few thousand pounds of supplies they propose to replace it with a few thousand pounds of hibernation equipment. Plus risking the lives of the passengers.

By time we need hibernation to travel the stars we will not need it.

By: Mike Borgelt

Mike Borgelt — Sat, 29 Apr 2017 00:45:59 +0000

Localfluff, you are kidding about that turbolift aren’t you? Those NIAC awards look like they were all published on April 1.
Did you read the comments? About like the utterly stupid Martian evacuated airship idea that got a NIAC award.
Were there any engineers on the awards panel or were they all arts/humanities grads without a clue, who did arts/humanities because there was no physics or math involved?

By: Mike Borgelt

Mike Borgelt — Sat, 29 Apr 2017 00:37:26 +0000

Yeah, we can go to Mars for a “flags and footprints” mission with Hohmann transfers and zero gravity but that is all it will be.
Then we can wait another 60 years before going back.
In space we can generate gravity at will. We know short periods of zero gravity aren’t all that harmful and are fun however serious longer term living or settlement on the Moon, Mars or other moons in the solar system are going to depend on whether the human body can tolerate much less than one gravity without serious problems.
If not, any mining/resource extraction on these bodies may be a similar model to Australian mining camps/offshore oil and gas rigs where workers are flown in for their shifts and flown out home for time off. “Home” will be rotating space habitats.
We should find this out sooner rather than later. There was going to be a variable gravity facility on the ISS at one time but got cancelled in favor of torturing astronauts in zero gravity.
For the long term future of humanity in space I cannot think of a more important project than finding out the effects of significantly reduced gravity on people, animals and plants.

By: Edward

Edward — Sat, 29 Apr 2017 00:05:43 +0000

John E Bowen wrote: “I understand, any group can only offer the solutions it knows”

When all you have is a hammer, every problem looks like a nail.

Chris is right, fix the problem and find or invent the correct tool rather than use the hammer.

LocalFluff oversimplifies. In addition to muscle loss there are bone loss issues and eyesight concerns. Radiation is of even more concern than these issues. Radiation may be a reason to consider a faster transit time than the basic Hohmann transfer orbit.

Here is a paper that shows the delta V needed for various transit times, and uses historic Mars missions to show previous solutions and computes delta V vs. transit times for possible 2018 missions to Mars:
http://ccar.colorado.edu/asen5050/projects/projects_2012/sparks/
“It has also been shown that shorter transfer times are available during the 2018 launch window which may be useful for human missions.”

It shows that, as compared to the Mars Science Laboratory mission, a less than 6% increase in delta V can result in more than a month and a half saved on the voyage. It also shows the importance of choosing the correct departure date. For the 2018 launch window, “it is possible to achieve very short times of flight with achievable ΔV. For the launches that begin on June 1st, it is possible to reach Mars in around 125 days or about 4 months.“

By: Chris

Chris — Fri, 28 Apr 2017 10:53:51 +0000

I like John’s approach “fix the problem” don’t create a new one.

By: LocalFluff

LocalFluff — Fri, 28 Apr 2017 08:33:14 +0000

Concerning simulated gravity, here’s a non-rotating proposal picked for NIAC funding. Intermittent acceleration load, like jumping on a trampoline.
http://www.parabolicarc.com/2017/04/28/niac-phase-award-turbolift/

By: LocalFluff

LocalFluff — Fri, 28 Apr 2017 06:28:20 +0000

John E Bowen,
A Hohmann transfer with chemical propulsion takes 6-9 months. Hundreds of astronauts have been in microgravity that long without problems. So simulated gravity through spinning isn’t necessary for going to Mars. It is a luxury for a future with a much larger space economy. Especially since the lower gravity there compensates for lost muscle mass. And the best way to find out if Martian gravity is good enough long term is to go there and try it out. We have reduced gravity sites for free out there, no need to build any simulation of them.

I’ve never heard of any medical interest in a rotating reduced gravity lab. For human space flight purposes it is not needed in the foreseeable future, that’s why no space agency ever has been interested in it. Nor do we have to travel faster than the most economical Hohmann transfer.

By: Please fill out this field

Please fill out this field — Fri, 28 Apr 2017 03:55:31 +0000

I agree, John’s comments are totally right. We want to fund research on Orion nuclear pulse spaceships pushing giant spinning wheels encased in feet of radiation shielding ice with a plasma radiation shield around that. The crew could host a reality show instead of arriving at their destination semi-retarded.

By: wayne

wayne — Fri, 28 Apr 2017 01:14:44 +0000

John-
Good stuff!

pivoting slightly…

“Hibernation”
short indie S-F from 2012 (pre Interstellar)
https://youtu.be/-winh9Bldxg
(16:42)

“Joseph is an astronaut set to go where no man has gone in the Universe through the hibernation program. But something is wrong between him and his instructor Claire, and the countdown for the lift-off is on.”

By: John E Bowen

John E Bowen — Thu, 27 Apr 2017 23:25:13 +0000

This is interesting research and, yes, it is unfortunate that the animal rights groups have so much sway over this and so much other research. I agree with this (hibernation) research, at least at the NIAC level of funding. I respect that, and who knows what good things might come out of it in the future.

But for actual development of travel to Mars and the asteroids, the “D” in R&D, I want to see faster spacecraft, period. Let’s get real. There was a time when most people who could choose, i.e. had the money, traveled the Atlantic in nice ocean liners. Then what happened? Did they ask for more special drugs, artificial hypothermia, so they could live in a state of torpor until arriving in Liverpool? No, when aircraft became larger and more reliable, people deserted the ocean liners for air travel. It takes more energy per passenger mile; so what?

OK, I realize I’m letting off some steam, but it’s not the first time a space problem comes up, and a group of doctors says, “Hmm, we have these nice drugs we want to try out.” Take radiation exposure; drugs might be absolutely necessary in the short run, provided they work; however, the real answer is sufficient radiation shielding, whatever that weighs, whatever it takes.

The same thing goes for the micro-gravity. I’m not against the research in this area either, and I certainly want to continue doing everything possible for those on the ISS to counteract and ameliorate the damage. But it seems to me the best cure for micro-gravity debilitation is gravity, plain and simple. Further, I wish we knew how much partial gravity would be enough, 10%, 16%, 38%? It would have been nice to find out, but apparently, the answer is “well, spinning structures are hard; we’re too slow and too simple to figure them out. But we have these new drugs we’d like to try . . . ”

I understand, any group can only offer the solutions it knows, and medical doctors have theirs. I look forward to the time, powered by lots of mined propellant and lots of solar energy, that the engineers can have their turn at solving these problems.