The Future of Space Travel: Can We Protect Our Brains from Radiation on Titan?

[Astronuc]

https://blogs.scientificamerican.com/guest-blog/lets-colonize-titan/

I'm thinking, look at all the 'fossil fuel', actually hydrocarbons. Send the petrochemical industry first so they can plasticize the moon.

The cancer-causing potential of this powerful radiation has long been known, although it remains poorly quantified. But research in the last two years has added a potentially more serious hazard: brain damage. GCRs include particles such as iron nuclei traveling at close to the speed of light that destroy brain tissue.

Actually, GCRs are fairly well characterized. Doesn't even have to be Fe. Any energetic nuclei in the > keV level will cause damage, not only through ionization, but also through spallation reactions that cause additional ionization, in addition to changing elements (chemistry).

 

[DaveE]

You first, LOL.

Plus, new word for me "spallation". Excellent!

I'm always struck in the whole "colonize space" discussions how the option of taking care of our own planet is completely ignored. With a miniscule fraction of the resources required (per person) to live on these planets we could make an excellent home here. Threats to Earth like asteroids, nuclear war, or pollution are easier problems to solve. It's like people want to give up and run away from their responsibilities here. How will that work for them in the long run? Where will they go after Titan? Or maybe they are just trying to fulfill irrational "Star Trek" like fantasies? Let's work on "warp drive" here first before we worry about alpha-centauri.

Also, why can't we study things like radiation in the solar system without always tying it to colonization? Does every scientific inquiry have to have an economic justification?

It's a nice thought experiment (or maybe a fever-dream), but that is all it is for now.

\\ --- END OF RANT ---

 

[Haborix]

You first, LOL.

Plus, new word for me "spallation". Excellent!

I'm always struck in the whole "colonize space" discussions how the option of taking care of our own planet is completely ignored. With a miniscule fraction of the resources required (per person) to live on these planets we could make an excellent home here. Threats to Earth like asteroids, nuclear war, or pollution are easier problems to solve. It's like people want to give up and run away from their responsibilities here. How will that work for them in the long run? Where will they go after Titan? Or maybe they are just trying to fulfill irrational "Star Trek" like fantasies? Let's work on "warp drive" here first before we worry about alpha-centauri.

Also, why can't we study things like radiation in the solar system without always tying it to colonization? Does every scientific inquiry have to have an economic justification?

It's a nice thought experiment (or maybe a fever-dream), but that is all it is for now.

\\ --- END OF RANT ---

Maybe space is just another way for people to play out the Hero's journey (they'll come back home; it might just take awhile).

 

[Jarvis323]

You first, LOL.

Plus, new word for me "spallation". Excellent!

I'm always struck in the whole "colonize space" discussions how the option of taking care of our own planet is completely ignored. With a miniscule fraction of the resources required (per person) to live on these planets we could make an excellent home here. Threats to Earth like asteroids, nuclear war, or pollution are easier problems to solve. It's like people want to give up and run away from their responsibilities here. How will that work for them in the long run? Where will they go after Titan? Or maybe they are just trying to fulfill irrational "Star Trek" like fantasies? Let's work on "warp drive" here first before we worry about alpha-centauri.

Also, why can't we study things like radiation in the solar system without always tying it to colonization? Does every scientific inquiry have to have an economic justification?

It's a nice thought experiment (or maybe a fever-dream), but that is all it is for now.

\\ --- END OF RANT ---

As long as something like this doesn't happen I guess.

But in reality, do most people really care about saving the planet, or securing a nice future for Earth and humanity? Maybe, but in the world we live in now, selling things dishonestly is pretty much standard practice and most people know it and accept it. The romanticism, adventurousness, and excitement that people use to sell things like space colonization are probably mostly another example of that. It's probably actually mostly about money, mining, war, and dominance. Space is the new frontier and with the technology opening things up, there is a new race underway that will ultimately determine the future superpowers, and super-wealthy that rule over the solar system. So it's one of those things where if one doesn't do it, someone else will, and we've seen how that type of situation has played out historically.

 

[Astronuc]

I'm not advocating colonization of Titan or any moon, at least not until we solve problems here on earth. I was amused by the article.

I know folks who have been studying GCR for some time, and some for the reason of radiation exposure to astronauts on ISS and lunar missions. About 35 years ago, where some colleagues and I were looking at manned missions to Mars and robotic missions beyond, a big concern was solar proton events with some concern of GCR, especially for long duration flights. My solution was to place water, air/oxygen, and propellant around the living quarters to use as a shield, in addition to the structural alloys that would contain the water, air/oxygen and propellant.

GCR has been studied for a long time.

At 1 AU, outside of the Earth’s magnetosphere, the GCR flux is nearly isotropic and spans energies from 10⁶ to ~10²⁰ eV. Particles with these energies are moving a significant fraction of the speed of light and are able to easily penetrate the thin shielding of most spacecraft . GCR provide an ever present radiation hazard to biologic materials and electronics in space.

https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1002/swe.20051

https://www.nasa.gov/sites/default/files/files/5_Slaba_NAC_042015_v6_TAGGED.pdf

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3000669

 

[gmax137]

RANT ---

Well, it (moving on to greener grass) is what we do. From a small tribe or two somewhere is east africa humans eventually have come to dominate nearly every square foot of the planet. Colonizing Titan (or wherever) is just a continuation of the story.

Will colonization of other worlds be hard? Of course. But if you could come back in 500, or a thousand years what would you expect to see? Or maybe 10,000 years? Seems to me it is just a question of time.

 

[PeroK]

Well, it (moving on to greener grass) is what we do.

Titan is "greener"?

 

[phyzguy]

To quote Robert Heinlein, "The Earth is just too small and fragile a basket for the human race to keep all its eggs in." We need to spread out to ensure our future survival.

Edit: To be clear, I'm not supporting the Titan idea. That seems crazy to me. But we need to move beyond the Earth, with the Moon and Mars the logical first steps.

 

[Vanadium 50]

Titan is "greener"?

Kind of an orangey-brown, I think.

 

[Twigg]

I'm thinking, look at all the 'fossil fuel',

I feel like by colonizing Titan, all we'd end up doing is increasing Titan's fossil fuel reserves emphasis on the "fossil" part

My solution was to place water, air/oxygen, and propellant around the living quarters to use as a shield, in addition to the structural alloys that would contain the water, air/oxygen and propellant.

Propellant is liquid O2 and H2, right? So if I'm understanding correctly, you'd need a layer of vacuum around the living quarters for thermal insulation, then the O2 and H2 with some wall to keep them separate? Do you think having the propellant everywhere like that causes a large heat drain (blackbody radiation from the room temp living quarters through the vacuum layer over a large surface area)? I don't have a good sense of scale for this, just curious

 

[nuuskur]

Let's Go! LOL

 

[Astronuc]

Propellant is liquid O2 and H2, right?

That would apply to a chemical rocket. My colleagues and I were considering nuclear propulsion, but nuclear thermal and nuclear electric, with a variety of propellants, from liquid H₂, ammonia, methane, and my favorite, diborane, B₂H₆. Volumes of water and oxygen would be separate for life support.

Cyrogenic storage of large volumes of liquid is problematic, especially as the liquid is depleted and 'sloshing' becomes an issue. There were numerous other challenges as well, with respect to energy generation and its shielding, and the details of the propulsion system. One of the most significant factors is 'how fast to get to destination'. Another significant consideration is the specific energy of the system, as well as specific impulse.

 

[Twigg]

@Astronuc Ah ok that makes sense. Yeah, for some reason I thought you were talking about design for space stations orbiting the earth. Now I get you about different propellants and about range being the main problem.
Yikes, sloshing doesn't sound good when you're trying to approach a moon/planet and stick a landing.

 

[Vanadium 50]

my favorite, diborane, B₂H₆.

Think you could get your spaceship to lift off with the weight of all those warning labels?

 

[Astronuc]

Diborane would not be a propellant fuel from the Earth surface. It would have to be frozen or otherwise produced in space. It's more explosive than hydrogen; basically, there is no safe concentration in air (very low flash point and LEL).

It has been used in terrestrial applications: https://en.wikipedia.org/wiki/Zip_fuel

The Navy considered converting all of their jet engines to Zip and began studies of converting their aircraft carriers to safely store it.

In testing, the fuels proved to have several serious problems and the entire effort was eventually canceled in 1959.

Yeah.

Think you could get your spaceship to lift off with the weight of all those warning labels?

No Smoking!

We also looked at electromagnetic (aka, railgun) launch systems. In both directions.

 

[Twigg]

We also looked at electromagnetic (aka, railgun) launch systems. In both directions.

The "both directions" aspect of that sounds really fun. Is the idea to pack up a portable railgun catapult in the spaceship, and assemble it on the other side with only tools / materials that can fit in the spaceship? That's pretty friggin' cool. Engineers and machinists would have a field day with that design.

"Can we pack the milling machine? Pretty pleeeaaaaaaase?" -what I would say, probably