Space travel - getting to from space / moon

[paulsutton]

Asking here as it seems more of an engineering question

Looking at the recent spaceX launch, (ok it failed) there seems to be a move to build bigger and bigger rockets to take us in to space.   How much is this really needed?

Would we be better off expanding the ISS (or I think the plan is to build a new space station) which can act as a launchpad to take us to the moon,  this could be equipped with what could be mini shuttle craft (like on star trek) that can dock and un dock as needed.

On earth we can already do vertical take off and landing with aircraft, so these shuttle craft would also be capable of this.

We currently have the smaller but reliable falcon rocket that could be perhaps used to launch components and supplies to the space stations.

Just seems that given what happened with the latest spaceX launch and the possible environmental damage caused the industry is going to be held more accountable.  Sticking with reliable technology could be a way forward  

 

[swansont]

You don’t save energy by doing it in stages, and assembling everything in space has the overhead of launching all the parts - including spare parts - into orbit. 

Plus, as the recent launch showed, launching can be fairly destructive to the surroundings, so you wouldn’t want to do that anywhere near a space station.

[mistermack]

What's today's motive, of going to the Moon? The first program was understandable, it was a first, and there was a huge amount to learn. But what's the motive today? Especially when automation has come so far, and information technology is so advanced. 
Putting a man back on the Moon isn't going to tell us much new stuff, that automation wouldn't. 

I have a feeling it's political. The Americans are worried that the Chinese might claim the Moon in the same way they're trying to claim the South China Sea. 

Another possibility is that, now that they know that there's lots of water on the Moon, they are looking on it as a source of rocket fuel, by splitting water using solar power. You make your rocket here on Earth, giving it just enough fuel to get to Moon orbit. Then you refuel it from a tanker of fuel produced on the Moon. That would give you plenty of scope to get to Mars and back, without having to expend vast amounts of energy lifting fuel up out of Earth's gravity well.

Lifting fuel off the Moon wouldn't take much energy because of it's low gravity and near zero atmosphere. 

Edited May 5, 2023 by mistermack

[exchemist]

5 minutes ago, mistermack said:

What's today's motive, of going to the Moon? The first program was understandable, it was a first, and there was a huge amount to learn. But what's the motive today? Especially when automation has come so far, and information technology is so advanced. 
Putting a man back on the Moon isn't going to tell us much new stuff, that automation wouldn't. 

I have a feeling it's political. The Americans are worried that the Chinese might claim the Moon in the same way they're trying to claim the South China Sea. 

Another possibility is that, now that they know that there's lots of water on the Moon, they are looking on it as a source of rocket fuel, by splitting water using solar power. You make your rocket here on Earth, giving it just enough fuel to get to Moon orbit. Then you refuel it from a tanker of fuel produced on the Moon. That would give you plenty of scope to get to Mars and back, without having to expend vast amounts of energy lifting fuel up out of Earth's gravity well.

Lifting fuel off the Moon wouldn't take much energy because of it's low gravity and near zero atmosphere. 

I think we definitely need Moonbase though, so long as we can have Gabrielle Drake to run it:

[mistermack]

Seems like a nice girl ! 

[Ken Fabian]

1 hour ago, mistermack said:

Putting a man back on the Moon isn't going to tell us much new stuff, that automation wouldn't.

For survey and exploration I think machines do it much better. But I think there is not much we do in space that requires or especially benefits by having astronauts - and having astronauts in space to advance the capacity to support humans in space seems a bit circular to me. Of course my pessimism around most space ambitions ought to be well known here.

Not sure laying claim to the moon is a driving factor for crewed missions to the moon - there are no resources of any value to exploit, or to seek to deny to enemies - but rather that developing and demonstrating the capacity to do it at all demonstrates technological superiority in areas highly relevant to military defense capabilities. China doing it would probably be seen as threatening to the USA, not for moon missions being in any way threatening but as evidence of China closing the gap on US technological superiority, which threatens the US military's "all theater domination" position.

Water for rocket fuel? Besides the need to demonstrate benefits of more distant space missions that require it - and deal with the problems of Hydrogen/Oxygen as rocket fuel - I think establishing the infrastructure needed on the moon would eat into any potential benefits. And for providing water in space maybe mining a near Earth asteroid - there are some that should have much lower delta-v requirements, that ought to have carbonaceous materials that water can be extracted from - could be more cost effective. I think asteroid mining is one of the few activities beyond Earth orbit with actual commercial potential, from resources that are known to be abundant.

 

[Gian]

When I was a kid it was often suggested that the moon would be the place from which to launch interstellar starships, and using the moon's own mineral resources it would perhaps be the place where starship are constructed as well.