Dangers to humans of deep space missions.

[Guest]

I have just watched this video. It talks about the dangers of deep space missions to humans. While one should carry out research and test the contents of such videos yourselves. It does pose questions as to how far away we are from realistically sending a human Mars mission. Perhaps we will wait for propulsion systems that could get to Mars in a few weeks.

[Stu]

Interesting video. I guess I’ve always taken the view that astronauts are volunteers, and providing they know and accept the risks then that is their decision. Ultimately any form of exploring is dangerous; the death rate on Everest is pretty high even though it is a well travelled route now. I suspect travelling to Mars would actually be safer!

[Guest]

I think the worry is that astronauts may become to ill to work before they reach their destination. Just wonder how close they are to putting new and faster propulsion systems online.

[Stu]

2 minutes ago, Grumpy Martian said:

I think the worry is that astronauts may become to ill to work before they reach their destination. Just wonder how close they are to putting new and faster propulsion systems online.

Yes, that makes some sense. I think they are a way from any dramatic improvement in speeds, I guess shielding is the main option?

[maw lod qan]

I dont know if they have all the answers they really want about the effects of O-g on bodies that have evolved to be in gravity.

For the time being I guess astronauts will have to balance the risk reward factor to justify what they personally sacrifice. 

If someone would have offered me the chance to go into space, but would have said when you get old, your joints might hurt all over, you might not see or hear really well and you hair will turn gray, I would have done it in a minute.

Already got all that just from working here on terrafirma with out all the fun!

Edited June 8, 2020 by maw lod qan

[Davey-T]

Wonder how they're progressing with the suspended animation of humans, I imagine somebody is working on it if we're planning on travelling to other stars, failing the invention of the warp drive it's the only way.

Bonus of returning younger than all your contemporaries you left behind 😁

Dave

[Ags]

I know NASA has been doing some research on hibernation - not the same as suspended animation but along the same lines. If you can keep the astronaut still for the entire trip, then you can pack shielding around them. If they are awake and moving around, the mass of the shielding becomes prohibitive.

Edited June 8, 2020 by Ags

[Dr Strange]

The gravity issue is (relatively) easily solved without complex systems. Simply spin the spacecraft. Here is an article on it:

https://www.wired.com/2015/08/spinning-spacecraft-martian-work/

The shielding issue is a much more thorny problem. From memory one option is water. For example the ISS uses a completely closed system for water:

https://www.nasa.gov/content/water-recycling/

The same would need to be done for a Mars or farther mission as well as a permanent base on the moon. However the inertia from a potentially unbalanced water storage would need to be addressed. The astronauts will need sufficient water to make the journey thus using it as part of a shield system or for that matter all of a shield system will return that value to the 3% stated in the video since they need to carry water anyway. The other heavy item will be food.  

Bottom line is the problem is somewhat difficult but not impossible. 

[Guest]

I think that deep space exploration is still several decades off. It will in my opinion only happen when much faster speeds can be attained. Thus drastically reducing journey and exposure times.

There is the psychological health of astronauts to consider aswell.

[Astro-Geek]

The crucial factor of speed (and therefore flight duration), appears to be the biggest limiter to our Earthbound mindset. 

Life support, food, air, water, radiation exposure, could all be accomodated if we could go fast enough.

With even Proxima Centauri being 4,200 light years away, it seems insurmountable.

Since space is a vacuum though, "warp" speed is just a matter of acceleration and deceleration, rather than maintaining thrust, as in our atmosphere's drag.

The Moon's 240,000 miles took 3 days, because we could only use the slingshot effect of the orbits.

If/when we can devise a way of accelerating and decelerating  in a vaccuum, we'll have cracked interstellar travel, with no "warp" speed limit, unless there's a "light speed barrier" ! 🤓

Edited June 9, 2020 by Astro-Geek

[Saganite]

1 hour ago, Astro-Geek said:

The crucial factor of speed (and therefore flight duration), appears to be the biggest limiter to our Earthbound mindset. 

Life support, food, air, water, radiation exposure, could all be accomodated if we could go fast enough.

With even Proxima Centauri being 4,200 light years away, it seems insurmountable.

Since space is a vacuum though, "warp" speed is just a matter of acceleration and deceleration, rather than maintaining thrust, as in our atmosphere's drag.

The Moon's 240,000 miles took 3 days, because we could only use the slingshot effect of the orbits.

If/when we can devise a way of accelerating and decelerating  in a vaccuum, we'll have cracked interstellar travel, with no "warp" speed limit, unless there's a "light speed barrier" ! 🤓

Not quite so bad as you fear as Proxima Centauri is 4.2 light years distant........

Edited June 9, 2020 by Saganite

[Astro-Geek]

11 minutes ago, Saganite said:

Not quite as bad as you fear as Proxima Centauri is 4.2 light years distant........

Damn...  just like my slide ruler days, I keep putting the decimal point in the wrong place.....  🤓

[Saganite]

47 minutes ago, Astro-Geek said:

Damn...  just like my slide ruler days, I keep putting the decimal point in the wrong place.....  🤓

Don't worry, I no longer trust my memory, I check everything...twice !........

Edited June 9, 2020 by Saganite

[Stu]

This all gets easier surely when we can travel near the speed of light, because the time would pass much more quickly for those onboard the space ship. Simples 🤣

Those sorts of time distortion effects do my head in I must admit. I looked this up yesterday and found some fun facts. If you travelled to M31 which was quoted as 2.537 million light years away at 0.99999999999992c, it would take you 1 year to get there from your perspective. Trouble is, it would still take 2.537 million years from the perspective of those remaining on Earth, so not much chance of anyone being home when you get back. Better hope you cancelled the milk and papers anyway 🤣🤣

Apparently travelling at the speed protons are accelerated at CERN you would get there in 384 years, so even then it remains a multi generational adventure!

I could see that at some point in the distant future, we might set off on one way voyages to distant stars as a way of protecting the species as Earth becomes uninhabitable. Using some form of constant acceleration like light sails or ion thrusters it might be possible to get to a significant percentage of the speed of light to make the journey manageable for those on board, provided they were setup to survive independently and for multiple generations. Can’t say it would be appealing to me! A long long time in the future I’m sure anyway.

 

[Nigeyboy]

14 minutes ago, Stu said:

2.537 million light years away at 0.99999999999992c, it would take you 1 year to get there from your perspective. Trouble is, it would still take 2.537 million years

Best thing here would be to invest £1 in a small savings bond - when you get home 5 million years later, it would have increased in value somewhat!! 

On a serious note though, I read something somewhere about spacecraft using an artificial magnetic field. Something large enough to protect a medium sized craft would need approx. 10kw of power. 

[Stu]

22 minutes ago, Nigeyboy said:

Best thing here would be to invest £1 in a small savings bond - when you get home 5 million years later, it would have increased in value somewhat!! 

That sounds similar to the Restaurant at the end of the universe in Hitchhikers Guide to the Galaxy as I recall. Make sure you invest a small amount At some point and then when you arrive you always have enough for a huge blow out! 🤣

[Nigeyboy]

Yeah, I also think Lister from Red Dwarf had a similar experience. I seem to remember he had accrued about 80% of the worlds wealth!!

[Ags]

1 hour ago, Nigeyboy said:

Best thing here would be to invest £1 in a small savings bond - when you get home 5 million years later, it would have increased in value somewhat!!

Well, actually investing £10 would be even better!