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“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

“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 2y ago
> 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.
- Robotbeat 2y ago
  Note that Mars’ surface has a similar radiation dose as ISS, as measured by the Curiosity rover. (This includes the quality factor.)
  - Retric 2y ago
    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.
  - idlewords 2y ago
    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 2y ago
      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.
      - idlewords 2y ago
        The 2-3x uncertainty in tumor risk comes entirely from the heavy ion component of GCR. Please go back and re-read that section of my post if you need to.
        Robotbeat 2y ago
        You are again picking one part of the risk to cherry pick to exaggerate the difference. There’s a risk in non-solid-tumor cancers as well. You have to take the whole value.
        Qem 2y ago
        It's because of this I like the concept for a one-way mission crewed by volunteer elderly astronauts. Why worry about developing a cancer 20 years down the line due to cumulative space radiation exposure, if your remaining life expectancy is lower than that, and you fully expect dying of old age in Mars anyway: https://web.archive.org/web/20101023054414/http://journalofcosmology.com/Mars108.html https://web.archive.org/web/20101023054414/http://journalofc... With the current worldwide ageing demographics, it would have the added benefit of providing an awesome feat to inspire seniors across the world to not go gentle into that good night, showing old age should burn and rave at close of day.
- somenameforme 2y ago
  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."
  - Retric 2y ago
    > The "To the Moon" speech was made in 1962 when we had basically no knowledge of space. Talk about hyperbole. The moon mission has been prepared for before that speech took place. It wasn’t just starting from scratch and hitting the moon in 7 years, instead the speech was more public disclosure of a deadline that looked achievable but would hit after his presidency (1960 + 8 being less than before the decade is out: 1970). The biggest problem is we already did the easy stuff. Playing tag with the moon is unbelievably easier than a permanent moon base or landing on Mars and getting back to earth.
    - somenameforme 2y ago
      Obviously we'd been wanting to go to the Moon before that speech, but there was no secret technology that we were just being coy about. We still knew nothing, had nothing and were in the process of figuring out what John Glenn's fireflies were during a flight where, if he wasn't such an uncannily good pilot, he probably would have died. Saying we'd be on the Moon in 7 years was not something that looked achievable except to the most fanatical of enthusiasts. To the average layman it would have sounded no less impossible than me saying we'll have a man on Mars in 7 years from today. And landing on Mars in many ways will be much easier than the Moon. Not only is the terrain broadly more hospitable, but you have an atmosphere to enable aerobraking which simplifies both landing and braking and enables various options (like some sort of parachute staging or backup). The biggest and really only complexity with Mars is its distance. Outside of that it's easy mode.
iab 2y ago
I think this shows a fundamental, widespread misunderstanding of space flight in general: > you’d be developing new technology all along the way Aerospace does not work like this. Hardware does not evolve until launch, it is frozen in time to allow for testing and flight qualification for subsystems, and systems as a whole.

Retric 2y ago

> 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.

Robotbeat 2y ago
Note that Mars’ surface has a similar radiation dose as ISS, as measured by the Curiosity rover. (This includes the quality factor.)
- Retric 2y ago
  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.
- idlewords 2y ago
  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 2y ago
    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.
    - idlewords 2y ago
      The 2-3x uncertainty in tumor risk comes entirely from the heavy ion component of GCR. Please go back and re-read that section of my post if you need to.
      - Robotbeat 2y ago
        You are again picking one part of the risk to cherry pick to exaggerate the difference. There’s a risk in non-solid-tumor cancers as well. You have to take the whole value.
        Qem 2y ago
        It's because of this I like the concept for a one-way mission crewed by volunteer elderly astronauts. Why worry about developing a cancer 20 years down the line due to cumulative space radiation exposure, if your remaining life expectancy is lower than that, and you fully expect dying of old age in Mars anyway: https://web.archive.org/web/20101023054414/http://journalofcosmology.com/Mars108.html https://web.archive.org/web/20101023054414/http://journalofc... With the current worldwide ageing demographics, it would have the added benefit of providing an awesome feat to inspire seniors across the world to not go gentle into that good night, showing old age should burn and rave at close of day.
somenameforme 2y ago
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."
- Retric 2y ago
  > The "To the Moon" speech was made in 1962 when we had basically no knowledge of space. Talk about hyperbole. The moon mission has been prepared for before that speech took place. It wasn’t just starting from scratch and hitting the moon in 7 years, instead the speech was more public disclosure of a deadline that looked achievable but would hit after his presidency (1960 + 8 being less than before the decade is out: 1970). The biggest problem is we already did the easy stuff. Playing tag with the moon is unbelievably easier than a permanent moon base or landing on Mars and getting back to earth.
  - somenameforme 2y ago
    Obviously we'd been wanting to go to the Moon before that speech, but there was no secret technology that we were just being coy about. We still knew nothing, had nothing and were in the process of figuring out what John Glenn's fireflies were during a flight where, if he wasn't such an uncannily good pilot, he probably would have died. Saying we'd be on the Moon in 7 years was not something that looked achievable except to the most fanatical of enthusiasts. To the average layman it would have sounded no less impossible than me saying we'll have a man on Mars in 7 years from today. And landing on Mars in many ways will be much easier than the Moon. Not only is the terrain broadly more hospitable, but you have an atmosphere to enable aerobraking which simplifies both landing and braking and enables various options (like some sort of parachute staging or backup). The biggest and really only complexity with Mars is its distance. Outside of that it's easy mode.

iab 2y ago

I think this shows a fundamental, widespread misunderstanding of space flight in general: > you’d be developing new technology all along the way Aerospace does not work like this. Hardware does not evolve until launch, it is frozen in time to allow for testing and flight qualification for subsystems, and systems as a whole.