Findings from 15 years of the International Space Station | Hacker News Reader

Findings from 15 years of the International Space Station

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77 pointsevo_933 comments

The AMS is interesting. It is CERN-like detector in space. Its the most expensive experiment on the ISS. It required a special act of Congress to extend the shuttle program one extra mission past its termination.

Early results show more anti-matter positrons in space than predicted. One interpretation attributes this to dark matter. AMS continues to collect data to refine results.

Are there any plausible theories for how dark matter would generate positrons?

Worth point out that (apparently) the only reason that the AMS was attached to the ISS rather than launched as an independent satellite is that it would have been hard to power it. So it leaches off the ISS solar panels.

https://en.wikipedia.org/wiki/Alpha_Magnetic_Spectrometer

Obviously, this can't be counted as more than a tiny fringe benefit of the ISS, since one could always have built a bigger, independent version of AMS with more solar panels (for a lot less than $150B).

Not sure that's a fair cost comparison - the ISS is reusable infrastructure whose power, propulsion (station-keeping), and structural investments are reused for multiple payloads. We just happen to be using the vast majority of it for life-support...

I just mean that if AMS is near the top of the list of reasons to have built the ISS, then either you have a bad list or the ISS probably didn't justify its enormous expense. Sure, it's possible that true value of the ISS was the in providing power and station-keeping for thousands of little experiments, but that seems highly unlikely. Better to just launch an unmanned station every couple years with a hundred experiments on board than to pay the fantastical expense of live astronauts.

Learning how to keep humans in space is a quite worth the expense in my opinion. One day or another, we'll have to figure it out.

This is an interesting point that has worried me in the past. The clock is ticking on this planet, and this solar system. But the more I've thought about it, the less convinced I am that this really justifies manned exploration at its current costs.

It will take some big changes to make space more habitable than Earth. If we can make a survivable enclosure in space, odds are that we can make a survivable enclosure on Earth and save the fuel costs, keeping us closer to some nifty raw materials. Massive impacts might make that unsafe,[0] but mostly we're looking at being engulfed by the sun in 5 billion years as a hard stop.

It's hard to really comprehend how much time that is. It's ten times longer than primates have been around. It's almost 1.5 times as long as all life has been around. Humanity as we know it will no longer exist at that point. If we have living descendents, they could be as unrecognizable to us as apes are to amoebas.

At that point we're just planning for "life in general" to survive, which we could accomplish by just sending probes with some spores or dormant bacteria on long voyages to distant habitable planets.

I wouldn't generally recommend procrastination, but this is probably a problem we can kick down the road a few generations. If we hit snooze for just 1/5000th of the remaining time we have, that'd give us a solid million years to up our technological game before tackling interstellar travel. At that point, the problem will probably have become either trivial or hopeless.

So ultimately, I'm not yet convinced that human survivability experiments are 1000 times as urgent as telescopes, probes, and rovers. That's what I'd be looking for to justify manned's absurd cost premium.

I was actually hoping this article would convince me otherwise, but if put up next to the top things we've learned from unmanned space experiments, I don't think it would compare very favorably. Definitely not 1000 times favorably.

I think we all yearn for the stars, and know this is the sort of thing we want to conquer, we want it to be among the great triumphs of humanity. But if we really want it, we should be smart about it. There's so much low hanging fruit we can get from unmanned. It could aid technological progress and deep understanding of the universe, leading to breakthroughs that ultimately leapfrog us past some challenges we'd meet if we just tried to bang our head against colonization today.

[0] Note that mammals have survived some crazy impacts before, probably by living underground. If we can make a survivable enclosure underground or under the ocean, that will be easier than making one and then launching it into space. Also, near earth object detection and mitigation programs are probably the best way to improve humanity's survivability given current technological capacities (ie, we can't build megastructures in space yet), and those programs compete for NASA money against humans in space too! Gradual climate change is unlikely to make Earth less habitable than Venus or Mars or space. Even if we lost most of our atmosphere and temperatures began to fluctuate by +/- 50 degrees, there'd still be advantages to building controlled structures on Earth rather than building such structures and launching them into inhospitable space. There are degrees of inhospitably, and Earth would have to become nightmarish (eg, probably engulfed by the sun) before we left.

Do you think that advances in interstellar travel capability will appear out of thin air? We make iterative improvements. The current state of the art will require humans to spend a lot of time in space to travel between planets, so research into how to keep them safe is valuable. Progress on more efficient and safer travel can't come unless we are actively experimenting and innovating.

My admittedly wordy post above was an attempt to respond to that exact argument. First, a clarification:

> Do you think that advances in interstellar travel capability will appear out of thin air?

No.

It should have been obvious from my post that this is a straw man, that I'm not arguing to halt all science and wait for advancements out of thin air. I want to pursue science efficiently, because we have limited resources. Also, the time scales involved here will radically change the nature of the problem beyond our comprehension.

This 5 billion year problem you want to start tackling today changes immensely if in 1% of 1% of that time our descendants are all clouds of digitally encoded consciousness that propagate primarily through EM radiation and psychic clouds of gas. I'm not saying that change is particularly likely, but some change on that magnitude is all but certain on this time scale (ie, 1.5 times as long it took proto-bacteria to turn into apes).

Suppose cavemen suddenly had a revelation that air transportation would some day change the world. It would be foolish and dangerous if they immediately devoted their free time trying to jump as high as possible, rather than just working on fire and wheels and spears.

Ultimately fire, wheels, and spears are foundational technologies for the disciplines that made flight and rocketry possible. So even though they seem like distractions from air travel, they're actually the most efficient path to solving that problem.

This is all the more obvious for probes, telescopes, and rovers. Those are the wheels, fire, and spears of space. Those all give us incrementally more information about the very nature of the universe, the nature of other possible planets, and how to build functioning intelligent machines that can survive in hostile environments. If there's some way to bend space to our will for instantaneous interstellar travel, or some way to get highly complex machines to shepherd us among the stars, we discover it there, not by putting a guy on a treadmill in microgravity.

Great comment which really made me think. You are right that unmanned projects are a no brainer. I would argue that both are important, and even with the budgets we have, we have been able to do both.

You made two assumptions that I would not, which make me believe we should continue to pursue manned exploration.

1) We have 5 billion years to figure this out.

There are many ways in which humanity could be wiped out on Earth, not just the death of the sun. Also I remember Elon Musk had a counterpoint to this as well that it's not a given that technology will always move forward. We need to exploit this chance while we have the capability.

2) The cost difference between a manned and unmanned mission are 1000 to 1.

That may be true for some missions, but I can't imagine that is anywhere near true for something like science missions for a station in low Earth orbit like the ISS. I would be interested in knowing what the actual cost differences are.

Good eye for assumptions, those are them. I'll defend one and weaken the other.

I. 5BY

I had a somehow longer version where I explained why I chose the 5 billion year figure. There are a lot of factors that could make life on Earth harder than it currently is, but really only a few that could make Earth less hospitable than Mars. Mars is basically just a gravity well. Maybe with usable water. An Earth worse than that is a long way off.

On the other hand, if Mars isn't enough, and we need interstellar travel, then we need either near instant travel or generational ships.

Generational ships mean we've mastered living in space without a planet. If we're sustainable in space without a planet, then orbiting destroyed Earth (for minerals) is as good as leaving it, unless the sun is expanding.

Near instant travel obviates the need for learning lessons about survival in space.

(I suppose we could get a tech that could take us to any planet in the galaxy in a FTL but five year long trip similar to sublight trips. That seems unlikely though.)

Impacts could destroy Earth. So sure, we should spend good money to look for asteroids (telescopes in space!) and learning how to divert them (with robots!). Note though, mammals somehow survived a mass extinction event from a massive asteroid before. So it'd have to be pretty big to prevent us from just making (maybe underground) shelters.

If the atmosphere or magnetic field weakened, there'd be a huge radiation hazard. Underground or undersea habitats would be more technologically feasible for us than space, though, and would provide better radiation shielding than anything we could build.

II. 1000:1 was silly.

Tech costs though, yeah. Good call. Maybe more like a factor of 10. Possibly as high as 50: http://www.tellmehowmuch.net/how-much-did-the-hubble-space-t...

http://www.businessinsider.com/mars-rover-curiosity-cost-eac...

http://www.nbcnews.com/id/14505278/ns/technology_and_science...

http://www.space.com/12166-space-shuttle-program-cost-promis...

None of these are easy to compare though. Is the Hubble platform equal to the ISS? How many shuttle launches equal one rover? I don't know. Maybe that brings them even further in line.

But if you ask me, at what exchange rate would I change unmanned tech points for manned tech points, based on the relative contributions to science from each, I think it'd be like 5:4 in favor of unmanned. Even if unmanned was more expensive, I think it's tackling some pretty interesting problems right now. I'm weird though, I know.

N.B. - Musk's point was really interesting too, thanks, kind of like "Foundation." I'm not sure where it takes me. It's like, "If humanity could develop only one more technology, what would it be?" Interstellar travel would be pretty compelling. I can think of interesting alternatives, but sure, interstellar seems like it might win.

We already had Skylab, which never gets the attention it deserves, and the Russians had Mir. They kept somebody up there for more than a year.

The true mission of the ISS was to serve as a jobs program for the shuttle.

The Apollo missions accomplished infinitely more--including launching Skylab--than the shuttle and ISS ever could have accomplished.

I looked at the ISS research in detail a few years ago, and there are several experiments counted as ISS research because they were on a space shuttle flight that went to the ISS. My point is that as you mention with the AMS, the benefits of the ISS are exaggerated in this way.

Overall, the research results of the ISS struck me nothing you'd put into even the top 100 discoveries of the year, and nothing worth the cost.

To see just how costly the ISS is compared to other research projects, see: http://www.scientificamerican.com/sciam/assets/Image/sad1015...

I never knew that the chemistry of flames and burning was so complex and poorly understood. Beautiful that flames are spherical in microgravity!

Not much to show for $19.6 million per day for 15 years.

The highest value of the ISS is not as a scientific experiment but an engineering undertaking. It's given us a lot of operational experience on long duration space habitats and space flight, as well as constructing and operating large structures in space that are launched via many payloads and assembled in orbit. From the ISS we have learned how one might actually build and operate the life support and habitat systems of a sci-fi scale spaceship like Discovery 1 (2001). Now that we have reusable rockets, it will soon be possible to actually launch and assemble such things in orbit somewhat economically.

IMHO the money could have been better spent but also might have been much worse spent. I'll take it.

It's not even that much money compared to, say, F-35 research.

Good point! I just checked out the cost, and reuters says that it's $1.45 Trillion! 10x the ISS cost, and hardly as inspiring. Even accounting for the 50 year lifespan vs the ISS' current 15 years, that's still 3x as much per day. Crazy.

The ISS delivered far more bang for the buck than quite a few other megaprojects.

Last but by no means least it provided a target for the nascent private space industry, leading to things like reusable rockets. That would have been possible without it, but it's being there helped.

It's telling that the only way to make the ISS look good is by comparing it to one of the biggest boondoggles in US funding history.

Nah that's just interesting because it's a 1000x expenditure with yet uncertain returns

Otoh, I've seen NASA ROI calculated anywhere from 5$ to 20$ per dollar spent. Hubbard places it at 8$. This article gives a good entry point to the topic http://www.21stcentech.com/money-spent-nasa-waste/

Oh I'm a big fan of NASA and think we ought to spend a lot on space since it's the future, but that doesn't change the fact that the Shuttle and the ISS were terrible investments. For one thing, the shuttle could lift only a fraction of what the Saturn V (used for Apollo and Skylab) lifted. In fact, Skylab actually had more space than even the largest module on the ISS (almost 2x) and was launched all in one go with a Saturn V.

Think about that: Skylab was bigger and was launched in a single day by a Saturn V. It also only cost $2.2 billion vs $150 billion for the ISS. If we had stuck with Saturn V's and the Skylab solution, we could have around 50 space stations right now--as opposed to just one. Or better yet, we could have colonies on Mars, and deep space manned missions (remember...the ship in 2001 A Space Odyssey wasn't supposed to be science fiction), and many more super-sized space telescopes, and who knows what else.

Anyway, I look at what we've done with NASA for the past 40 years compared to what we could have done and I can't help but feel like we squandered an incredible opportunity.

That operational experience dies out the longer we don't apply that hard-fought knowledge.

Are you being serious? Maybe you need to do some reading?

https://en.wikipedia.org/wiki/International_Space_Station

https://www.nasa.gov/mission_pages/station/main/index.html

I've often wondered why NASA never considers artificial gravity through a rotating structure to dispense with the problem of long-term zero-G on the human body. At least I have never seen a media report of NASA taking this seriously, and I have followed media reports of space topics since I was a child. There must be a reason for this. Numerous science fiction writers treated this concept as a given decades ago.

If these are the 5 key findings of the lengthy construction and 15 years of operation of the ISS, this is a pretty lame return (in terms of science) for a huge investment. I suspect the only other thing we can say is we have a lot more experience of human operations (activity) in space. Something to be said for that.

I expect it largely comes down to cost.

That and the fact that we have plenty of gravity on Earth. We go to space to study things that we can't study on Earth.

The force of gravity in low earth orbit is about 91.7% of the force at sea level.

The apparent force, which is what we experiment with, is much less.

But it's far easier to maintain prolonged free fall in orbit.

There is also about no experience with it, so a lot of work, money and mistakes are needed. Structural integrity is a big challenge. As I see it, it's not that people there do not think about it, it's just not feasible right now.

> I've often wondered why NASA never considers artificial gravity through a rotating structure

They most likely have considered this several times.

But to make it work, they would have to build an impractically large structure (it would have to vs twice the size of ISS to work at a reasonable speed) and deal with the difficulties of large rotating structures.

During the ISS program, space medicine has advanced a lot. With a specialized diet and training regime, astronauts have no measurable loss of bone mass any more.

15 years of continuous human presence in space is a huge achievement. At 150 billion dollars, equal to three months of US military spending, it's a bargain.

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