[bisby]

I feel like Musk said that transit times to Mars would be 3-4 months at the transfer velocities they were shooting for, and a slower transfer for something like Curiosity was 10 months.

How different would 12 months in orbit be from 4-10 months interplanetary? Even if this winds up being accurate for LEO (even with n=1), how relevant is it for going to Mars?

[_archon_]

In a brief search, it appears that the ISS is within Earth's magnetosphere and is largely protected from ionizing radiation e.g. [1]. The radation and possible craft shielding question is at the forefront of my mind; not only for a Mars crew, but for the plant seeds/seedlings they'd necessarily be bringing with them for an eventual food cycle. Any construction materials, fuels, etc. will have to either be shielded (heavy and bulky) or immune to changes from radiation. Also, Mars's magnetosphere is super weak compared to Earth's, so this is an ongoing concern after a successful transit and landing.

I'm thinking that best practice for a potential Martian would be to create a sperm/egg cold-storage repository before leaving Earth (in case they want kids after potentially and safely returning). Kind of a weird, radiation-related tangent.

[1] http://www.forbes.com/sites/jillianscudder/2016/08/23/astroq...

[mikeytown2]

I wonder if you could re-create a magnetosphere by wrapping the entire planet in wire. Thinking this would be feasible once cheap high temperature superconductors are available that don't "quench" [1]. Sigh.

[1] https://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_...

[namlem]

Thick plastic would provide adequate shielding from radiation, and could one day be made from local materials. Or we could just live underground. Fiber optics could be used to channel sunlight deep underground.

[toolbox]

In orbit there is still the significantly protecting effect of the Earth's magnetic field, which deflects much of the heavy ion radiation. This more massive radiatiom has different mechanisms of damage, and we're finding that it is likely more damaging in many contexts. So all-in-all, the space station ends up being a minor simulation of the much harsher interplanetary environment. I have several theories about how musk's team intend to solve this issue, mostly talking about surrounding the crew quarters with water. That being said, this problem is still largely unsolved and remains one of the biggest barriers to interplanetary human spaceflight.

[mikeytown2]

Really good podcast about this topic: RPR 11 – Radiation and Propulsion Expert: Dr. Joseph Parker[1]

[1] http://radio2.marssociety.org/2017/01/18/rpr-11-mars-radiati...

[wolf550e]

Dr. Robert Zubrin on the radiation on the way to Mars:

https://www.youtube.com/watch?v=3UChuIqIKF4&t=1031