SPACE

[pogo]

Long past time when they should have. I guess the recent flurry of results from unmanned missions sealed it, but it’s been clear for many years. You want to explore the solar system, search for planets outside it, or study fundamental physics? ISS is no use as it cannot travel, is in too low an orbit for observation as Earth is in the way half the time, and is too noisy for many sorts of observations and experiments. Other missions are returning reams of data and media, but not ISS.

All it’s good for is experiments about putting people in space. But that is rather a circular justification as we have nowhere else to send people. A Mars mission or a Moon base are at the moment just speculative. The only place to send them now is ISS, which is being used to prove we can send them there.

[Darkflame]

Its the only way we have to study the effects of microgravity over long periods though. Or even anything other then very very short periods.
Be it humans, animals, plants, or materials.
The ISS is a whole different, unique, environment that can not be replicated on earth. Thats valuable in itself - regardless of sending people elsewhere.

Besides, have we really already learnt everything about humans living in space for long periods?
Sending people successfully to other places will forever be speculative unless we have a good enough understanding about how to keep people alive up there. Not just biologically speaking, but in terms of maintenance, tool replacement etc. ISS is "safe" because earth is nearby - anything going wrong on the way to Mars, its much better to be prepared for it in advance with tested solutions.

So its only really circular if you really are never going anywhere else. In all other cases its a probably a necessary prerequisite.

-

Also, thanks for the scale.

[pogo]

It’s not that we will never send anyone to Mars. If we don’t wipe ourselves out I’m sure we will do it one day. But until we have concrete plans to do so it’s hard to see how ISS helps.

Maybe a Mars mission is announced next year. Or maybe 50 years from now by which time science and technology has moved on so much that ISS is woefully primitive. Maybe we can put people in stasis. Maybe can build a much larger environment with space for many more people or even a whole biosphere. Maybe we can include 2001-like centrifugal gravity. Maybe robots and AI mean human space crew is not needed.

So, no, ISS is not necessarily useful even if we do end up sending people to Mars, or to live on the Moon, or to tour the Asteroids. These missions are inconceivable now as we have major problems to solve before we can even consider them. By the time we solve these problems, and even in solving them, we may find we have moved so far beyond what’s possible today that most of what was discovered by ISS is obsolete.

[pogo]

oops double post

[zip accident]

It’s not that we will never send anyone to Mars. If we don’t wipe ourselves out I’m sure we will do it one day. But until we have concrete plans to do so it’s hard to see how ISS helps.

Maybe a Mars mission is announced next year. Or maybe 50 years from now by which time science and technology has moved on so much that ISS is woefully primitive. Maybe we can put people in stasis. Maybe can build a much larger environment with space for many more people or even a whole biosphere. Maybe we can include 2001-like centrifugal gravity. Maybe robots and AI mean human space crew is not needed.

So, no, ISS is not necessarily useful even if we do end up sending people to Mars, or to live on the Moon, or to tour the Asteroids. These missions are inconceivable now as we have major problems to solve before we can even consider them. By the time we solve these problems, and even in solving them, we may find we have moved so far beyond what’s possible today that most of what was discovered by ISS is obsolete.

I do see Leo being passe, but surely the ISS can be boosted somewhere higher? There is a lot of capacity in it that could be reused.

[pogo]

I do see Leo being passe, but surely the ISS can be boosted somewhere higher? There is a lot of capacity in it that could be reused.

Not easily. It is big, very big. And that has two consequences. First it would take a lot of energy to boost it up higher, especially as you would want it in a stable higher orbit. Second it might require a lot of engineering in addition to strapping an engine to it, to reinforce its spread out and only lightly held together pieces as it’s moved.

A downside of putting it in a higher orbit is higher visiting costs for astronauts. That’s probably why it’s in low-earth orbit to begin with. And I don’t really see what it gets you; the environment is not really any different. Apart from longer trips the experience for astronauts is the same. You are still too close to Earth and to a noisy, vibrating space station for much science.

[gumboot]

Really need the means to build (or at least assemble) substantial stuff in space. You still have your fundamental energy costs of getting materials up there, but you wouldn't have to overcome the gross impracticality of getting a very big rocket launched inside of an even bigger rocket.

[pogo]

Long term I think the only sensible approach is to make use of what is up there already. I mean materials found in asteroids and comets, away from planetary gravity wells. Building materials such as iron for steel. Carbon, hydrogen and oxygen for fuel and for biosystems.

Thankfully I’m pretty sure that is already up there. We have evidence from meteorites, from visible surveys of asteroids and comets, and now from visits to them. After boiling or melting away in Earth’s early history many of the chemical elements in the Earth’s crust we rely on came from later asteroid bombardments, which suggests they are just the same materials.

But it really is a long term project. It will take a long time to develop the technologies, even longer to build up the capacity. It probably needs new ways of thinking and planning, as it will involve such long timescales before it leads to manned missions. But I’m sure we will do it. Not only will it make manned space travel affordable and scalable but it will eventually be self sustaining and even profitable, if used to find materials that are in short supply on Earth.

[zip accident]

I do see Leo being passe, but surely the ISS can be boosted somewhere higher? There is a lot of capacity in it that could be reused.

Not easily. It is big, very big. And that has two consequences. First it would take a lot of energy to boost it up higher, especially as you would want it in a stable higher orbit. Second it might require a lot of engineering in addition to strapping an engine to it, to reinforce its spread out and only lightly held together pieces as it’s moved.

There's no need to move it fast, it can be moved over months and years. It already has an engine or it would have de-orbitted by now. There are tons of aluminium in it, and most of the parts could be reused even if the habitat section had to be recycled, which I doubt is really necessary. Ore from asteroids would need smelting, refining and shaping before it could be used, the ISS is already make of chunks of metal, and is already in orbit.

A downside of putting it in a higher orbit is higher visiting costs for astronauts. That’s probably why it’s in low-earth orbit to begin with. And I don’t really see what it gets you; the environment is not really any different. Apart from longer trips the experience for astronauts is the same. You are still too close to Earth and to a noisy, vibrating space station for much science.

Cis Lunar space is a higher orbit. Yes it will be expensive to get to, but if that's where they're aiming to get to anyway, that's not a problem.

[zip accident]

I do see Leo being passe, but surely the ISS can be boosted somewhere higher? There is a lot of capacity in it that could be reused.

Not easily. It is big, very big. And that has two consequences. First it would take a lot of energy to boost it up higher, especially as you would want it in a stable higher orbit. Second it might require a lot of engineering in addition to strapping an engine to it, to reinforce its spread out and only lightly held together pieces as it’s moved.

There's no need to move it fast, it can be moved over months and years. It already has an engine or it would have de-orbitted by now. There are tons of aluminium in it, and most of the parts could be reused even if the habitat section had to be recycled, which I doubt is really necessary. Ore from asteroids would need smelting, refining and shaping before it could be used, the ISS is already make of chunks of metal, and is already in orbit.

A downside of putting it in a higher orbit is higher visiting costs for astronauts. That’s probably why it’s in low-earth orbit to begin with. And I don’t really see what it gets you; the environment is not really any different. Apart from longer trips the experience for astronauts is the same. You are still too close to Earth and to a noisy, vibrating space station for much science.

Cis Lunar space is a higher orbit. Yes it will be expensive to get to, but if that's where they're aiming to get to anyway, that's not a problem.

Two Skylabs in my lifetime would be three too many.

[gumboot]

But it really is a long term project. It will take a long time to develop the technologies, even longer to build up the capacity. It probably needs new ways of thinking and planning, as it will involve such long timescales before it leads to manned missions. But I’m sure we will do it. Not only will it make manned space travel affordable and scalable but it will eventually be self sustaining and even profitable, if used to find materials that are in short supply on Earth.

So it may or may not be easy to launch an asteroid-harvesting mission directly from earth in an all-in-one package rather than to launch pieces to be assembled in space before carrying on. I couldn't say. But at some point we'll need to get all stages of fabrication off of earth.

Perhaps we should start by scooping up old satellites and refining those for raw materials, and then set about trying to get something up there that can build a builder robot slightly less primitive than itself.

Which obviously comes down to the trite "can your 3d printer print a better 3d printer?", which is perhaps an altogether terrestrial question for the moment.

Robot-building robots. We need to think seriously about it.

[zip accident]

Oops; I didn't notice the double post in time to edit one to nothing.

[zip accident]

Ceres is a comet:

https://www.newscientist.com/article/mg ... e-a-comet/

[merman]

Tim Peake off to the ISS this week for his 7-month mission.
Launch vehicle is assembled.

Coverage on the BBC
Horizon: How To Be An Astronaut, BBC2 Sunday 8pm
Blast Off Live, BBC1 and BBC News Tuesday 10:30am
Stargazing Live: Brit In Space, BBC2 Tuesday 7pm

[merman]

Ground Control to Major Tim...

He's on his way!