[ZDan]

Originally Posted by Irace86.2.0

The fastest train ever was a French train on wheels and not a Maglev train, so I don't know if wheels are limiting, so that could also be why he changed.

Wheels are no prob. The point is that "air bearings" operating in a vacuum *or low-pressure* tube was a dumb idea in the first place.

I don't know if creating a lower pressure environment is a terrible idea. It is the sole reason why planes fly so high. Are you saying it is laughable because keeping the tube lower pressure would be hard or prohibitively expensive or dangerous or all or what?

Yeah, maintaining a vacuum or "low pressure" over any decent distance is problematic. Very difficult, very expensive, very susceptible to seismic events, vandalism, terrorism, etc. Vacuum train idea has literally been around over 100 years, apparently "invented" by the father of modern rocketry, Robert Goddard. Yeah, greatly reducing drag is a great idea! But doing that by flying at 40,000 ft in an airplane is not really a problem. Creating and maintaining a vacuum or low-pressure environment in an elongated tube for miles and miles and miles, not so practical. Ol Muskie repeatedly talked and laughed about how *EASY* it is though. Far from it... High-speed rail is a totally doable thing. Hyperloop is not really workable.

A three year mission to mars wouldn't be a death sentence. Are you saying you know the risk of cancer is greater than say smoking tobacco? Around 1.3 billion smoke tobacco including more than 10% of the US population, and even more live around second hand smoke, so finding risk-tolerant people wouldn't be a problem. Several astronauts were smokers including Buzz Aldrin.

No reason to bring up or talk about smoking to muddy waters. Already said there are any number of people who would sign up for a Mars mission despite the risks.

People would be exposed to FAR greater solar radiation and also cosmic rays. All the time logged by astronauts in low earth orbit where they are protected by the Van Allen belts does not translate into survivability outside the V.A. belts. Even lunar missions on the scale of days are far far more risky as solar activity can injure or kill astronauts outside the belts. Obviously a mission to Mars would leave them exposed for much longer. Building a ship with sufficient shielding makes the mission impractical, unless we want to spend a significant portion of GDP on it for years/decades. With the tech we have now or may have in the next say 10-20 years, I don't see it happening.

Staying on mars would require tunnels, which is why there is The Boring Company.

I don't see any giant boring machines being sent to Mars any time soon...

NASA discusses using lava tubes in its mission plan for long term housing in the initial years to avoid larger radiation doses.

Hell of a lot more realistic than sending massive boring machines...

NASA will likely extend their limit on acceptable radiation levels like they did recently, so astronauts can go to Mars, but what really is going to happen is Optimus

Optimus? I don't think humanoid robots would be of much use, but anyway, I think Optimus is way behind what Boston Dynamics has been doing.

and other robots and autonomous vehicles will be sent to Mars to build tunnels, structures, mine materials, terraform the atmosphere and surface, and pave the way for humans to be able to survive on mars much easier.

None of that is happening in our lifetimes...

With that said, current age or age of death:

Again, the environment outside the Van Allen belts is far more hostile/deadly vs. ISS/low earth orbit.

People seem to think that going to Mars is just a step beyond going to the moon. It is one or two orders of magnitude more difficult. I don't think it's realistic with chemical rockets. Unless you decide that a 25% chance of survival is acceptable risk...