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Robotbeat | on: The Shape of a Mars Mission
“Current day technology” is sort of poorly defined because you can make new technology in one day. “Current tech” is a fake constraint, because even preparing for a launch in two years, you’d be developing new technology all along the way.

The annoying thing is that we could’ve been simulating long duration partial gravity using artificial gravity for decades, but NASA has refused to do so. For inexplicable reasons. If I had to guess, it’s due to the microgravity research community fiefdoms who have made a career of microgravity health effects and so don’t like the idea of directly addressing them using artificial gravity as it makes a whole career’s worth of work largely obsolete.

Retric | parent
> you can make new technology in one day.

Not if you want it dependable enough to entrust a multi billion dollar project and several people’s lives to it.

People talk about the moon mission like some massive conquest of space, but we needed to get the fuck off the moon much past sunrise or astronauts would have cooked. It was based on extremely limited oxygen supplies and involved significant radiation exposure that was only ok because again we ran away from an extremely inhospitable environment before things went wrong.

Even today the ISS benefits from earths magnetic field, its space light not a true replica of a mars mission.

somenameforme | root | parent | next
The "To the Moon" speech was made in 1962 when we had basically no knowledge of space. We'd only sent a man into Low Earth Orbit for the first time a few months prior. 7 years later we'd land a man on the Moon. And we'd repeat this several times over until Nixon effectively cancelled the human space program in 1972. Obviously 7 years is not one day, but I think 1 day was clearly figurative rather than literal.

The biggest problem is that people have really lost the ability to think big. There's always infinite reasons to not do something, and there will never be a perfect time. So at some point you simply have to choose to push forward. Like Kennedy put it:

"We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too."

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Robotbeat | root | parent
Note that Mars’ surface has a similar radiation dose as ISS, as measured by the Curiosity rover. (This includes the quality factor.)
idlewords | root | parent | next
It does not; see the paper cited in my other reply to you. GCR dose is 1.5-2x on Mars compared to ISS.

The mention of "quality factor" here just begs the question. The reason we need research on biological effects of high-Z ion exposure is that it has a different mechanism of damage, not captured by that paradigm.

Robotbeat | root | parent
GCR /alone/, maybe, but it’s, um, strange to pretend the substantial trapped radiation dose on ISS doesn’t exist, as you’re doing here (Table 2 in your linked paper shows the trapped dose at ISS is about equal to the GCR dose at ISS, so ignoring trapped dose makes your estimate off by approximately a factor of 2). It is the total effective dose (including quality factor) which matters, not cherry picking one particular source.
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Retric | root | parent
A significant part of that is because it’s much further from the sun.

A hypothetical 500 day mars mission is ~1 Sv optimistically which is something like 5% fatal cancer risk. A 3 year mission you’re well above that even before considering solar storms etc.

I think many would sign up for a mars mission especially as treatment improves, but there’s only so much wiggle room here.