A lot of those are papers on the effects of microgravity on human beings. Good stuff to know, but it’s a bit “self-licking ice cream cone”-esque – ISS studying how humans are effected by microgravity, so they can better stay on ISS in microgravity.
I’m not sure I’d say that, since the effects of microgravity are relevant to things like long trips to Mars. But in a sense, the medical work on ISS is free, or at least heavily subsidized. There will be people (subjects) on ISS, by definition. To conduct research on the medical effects of microgravity, you have to measure subjects which someone else is paying to send up there, for other reasons. I don’t think that’s true of any other sort of research conducted on ISS. For things like material science or fluid dynamics, the experiments have to be 100% funded as scientific experiments.
The pragmatic reality is that NASA has to utilize a variety of analogs with varying degrees of dependence on funding and politics of entities outside of NASA. Such an ecosystem of analogs also is necessary to address the various hazards of spaceflight that include but are not limited to weightlessness, not to mention the intractable confounds of research in an operational environment and the wicked problem of small N.
Although one could argue that the entire body of research suggests more persuasively that the cost of the latter is worth the benefits of viable deep-space travel.
I doubt if there are reliable estimates on the cost of adding artificial gravity to space vehicles since it changes the structural dynamics, which will be different for each spaceship design.
And we aren’t sure yet about the benefit side of it. Sure there will be a benefit, but you are referring to cost/benefit equations, which requires quantification on both sides, which we don’t have yet. The outbound trip to Mars will take far less time than the amount of time people have already spent on ISS. If as we are hoping spending time in Mars gravity either stabilizes the microgravity effects, or even better partly restores functionality, then the effects of the return trip should be manageable even with current mitigation techniques.
Yes it is also possible that degradation will continue on Mars, but at what rate we don’t know. Bone mass loss for example may or may not be linear compared to microgravity. And perhaps just having some amount of gravity will mitigate issues with fluid loading. We should have a better idea once people start spending time on the Moon, the effects shouldn’t be any worse on Mars.
Of course this doesn’t help on missions going further out than Mars, but that is likely far in the future and by then a lot of knowledge and experience will have been gained just by the normal process of going to the Moon and Mars, and yes spending time on space stations.
Then again a 1/3 g centrifuge on a space station would be nice as it would provide some good data. But that would be costly also, and with limited budgets it might be better to first get data from spending time on the Moon since the cost of that will be two-for-one like microgravity research is on ISS.
It would be nice to see even some back-of-the-napkin cost estimates though and compare them to (a) costs of R&D to date on the various effects of prolonged weightlessness, (b) costs of mitigations for health and performance effects of prolonged weightlessness, and (c) augmentation and resilience of impaired human performance on Mars after prolonged weightlessness.
I’m not sure how you could do a back of the envelope estimate. The usual approach in the field is to use parametric models, which are basically a fancy way to extrapolate from past, similar projects. That’s fine for things like communications satellites. It’s probably fine for something like the Gateway Power and Propulsion Element, since PPE is basically a modified communications satellite. But a spin-gravity spacecraft for a trip to Mars? The parametric models tend to explode when you apply them to really novel things.
Given a design, even a very rough concept, you could probably do a bottom-up cost estimate. But there are lots of possible designs (I like two modules connected by a 200-m cable, but other people hate that idea…) And a bottom-up cost estimate is a lot more work than a back of the envelope estimate.
Whatever one thinks about the ISS as a research platform, human research at NASA (including but limited to ISS) should be applauded for the openness of its metascience, that is, the science behind its decisions to fund various projects and platforms at various levels. The value of its metascience is not that its funding decisions are beyond reproach. To the contrary, and by definition, its metascience provides the potential for its decisions in science program management to be improvable and to become increasingly intelligible.
While its nice that human life sciences are pursued on ISS that wasn’t the original purpose. Reagan wanted space open to commerce to pursue research, new products, and expansion of the economy. On that ISS has not done the greatest. As far as the human life sciences, we could have learned much more about the value of G if we had kept the centrifuge module. It is a significant missing piece of the human life science puzzle.
I was the Payload Accommodations Manager at NASA for the Centrifuge Facility in the early 1990s – and as a space biologist I certainly agree. However I do disagree with your statement (minus any facts) that “ISS has not done the greatest”. Compared to what?
As compared with what it could be and could have been doing. For one, NASA took much of ISS funding earmarked for science and gave it to its contractors. For another in prior programs NASA did a lot to advertise capabilities to prospective but uninitiated experimenters, and they did a lot to streamline integration processes and they did a lot to assist the experimenters. I don’t see anything equivalent today.
A lot of those are papers on the effects of microgravity on human beings. Good stuff to know, but it’s a bit “self-licking ice cream cone”-esque – ISS studying how humans are effected by microgravity, so they can better stay on ISS in microgravity.
I’m not sure I’d say that, since the effects of microgravity are relevant to things like long trips to Mars. But in a sense, the medical work on ISS is free, or at least heavily subsidized. There will be people (subjects) on ISS, by definition. To conduct research on the medical effects of microgravity, you have to measure subjects which someone else is paying to send up there, for other reasons. I don’t think that’s true of any other sort of research conducted on ISS. For things like material science or fluid dynamics, the experiments have to be 100% funded as scientific experiments.
The pragmatic reality is that NASA has to utilize a variety of analogs with varying degrees of dependence on funding and politics of entities outside of NASA. Such an ecosystem of analogs also is necessary to address the various hazards of spaceflight that include but are not limited to weightlessness, not to mention the intractable confounds of research in an operational environment and the wicked problem of small N.
Or go on trips to Mars in microgravity so as to avoid the cost and complexity of a rotating centrifuge. Highly relevant.
Although one could argue that the entire body of research suggests more persuasively that the cost of the latter is worth the benefits of viable deep-space travel.
I doubt if there are reliable estimates on the cost of adding artificial gravity to space vehicles since it changes the structural dynamics, which will be different for each spaceship design.
And we aren’t sure yet about the benefit side of it. Sure there will be a benefit, but you are referring to cost/benefit equations, which requires quantification on both sides, which we don’t have yet. The outbound trip to Mars will take far less time than the amount of time people have already spent on ISS. If as we are hoping spending time in Mars gravity either stabilizes the microgravity effects, or even better partly restores functionality, then the effects of the return trip should be manageable even with current mitigation techniques.
Yes it is also possible that degradation will continue on Mars, but at what rate we don’t know. Bone mass loss for example may or may not be linear compared to microgravity. And perhaps just having some amount of gravity will mitigate issues with fluid loading. We should have a better idea once people start spending time on the Moon, the effects shouldn’t be any worse on Mars.
Of course this doesn’t help on missions going further out than Mars, but that is likely far in the future and by then a lot of knowledge and experience will have been gained just by the normal process of going to the Moon and Mars, and yes spending time on space stations.
Then again a 1/3 g centrifuge on a space station would be nice as it would provide some good data. But that would be costly also, and with limited budgets it might be better to first get data from spending time on the Moon since the cost of that will be two-for-one like microgravity research is on ISS.
It would be nice to see even some back-of-the-napkin cost estimates though and compare them to (a) costs of R&D to date on the various effects of prolonged weightlessness, (b) costs of mitigations for health and performance effects of prolonged weightlessness, and (c) augmentation and resilience of impaired human performance on Mars after prolonged weightlessness.
I’m not sure how you could do a back of the envelope estimate. The usual approach in the field is to use parametric models, which are basically a fancy way to extrapolate from past, similar projects. That’s fine for things like communications satellites. It’s probably fine for something like the Gateway Power and Propulsion Element, since PPE is basically a modified communications satellite. But a spin-gravity spacecraft for a trip to Mars? The parametric models tend to explode when you apply them to really novel things.
Given a design, even a very rough concept, you could probably do a bottom-up cost estimate. But there are lots of possible designs (I like two modules connected by a 200-m cable, but other people hate that idea…) And a bottom-up cost estimate is a lot more work than a back of the envelope estimate.
Whatever one thinks about the ISS as a research platform, human research at NASA (including but limited to ISS) should be applauded for the openness of its metascience, that is, the science behind its decisions to fund various projects and platforms at various levels. The value of its metascience is not that its funding decisions are beyond reproach. To the contrary, and by definition, its metascience provides the potential for its decisions in science program management to be improvable and to become increasingly intelligible.
While its nice that human life sciences are pursued on ISS that wasn’t the original purpose. Reagan wanted space open to commerce to pursue research, new products, and expansion of the economy. On that ISS has not done the greatest. As far as the human life sciences, we could have learned much more about the value of G if we had kept the centrifuge module. It is a significant missing piece of the human life science puzzle.
I was the Payload Accommodations Manager at NASA for the Centrifuge Facility in the early 1990s – and as a space biologist I certainly agree. However I do disagree with your statement (minus any facts) that “ISS has not done the greatest”. Compared to what?
As compared with what it could be and could have been doing. For one, NASA took much of ISS funding earmarked for science and gave it to its contractors. For another in prior programs NASA did a lot to advertise capabilities to prospective but uninitiated experimenters, and they did a lot to streamline integration processes and they did a lot to assist the experimenters. I don’t see anything equivalent today.