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Way to go SpaceX !!

 

https://arstechnica.com/science/2019/12/spacex-to-attempt-cargo-launch-upper-stage-experiment-for-second-time/

 

Incredible really, in a short space of time they have begun to eclipse the Atlas, which no one ever regarded as a reliable or safe booster in the first place. it took a John Glenn to have the balls, or stupidity, to ride that rocket.

 

SpaceX does it whilst keeping the booster for another shot.

 

I still think I'd prefer a next Gen Shuttle but this is fine for now.  🙂

 

Cheers

 

 

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1 hour ago, chrisg said:

Way to go SpaceX !!

 

https://arstechnica.com/science/2019/12/spacex-to-attempt-cargo-launch-upper-stage-experiment-for-second-time/

 

Incredible really, in a short space of time they have begun to eclipse the Atlas, which no one ever regarded as a reliable or safe booster in the first place. it took a John Glenn to have the balls, or stupidity, to ride that rocket.

 

SpaceX does it whilst keeping the booster for another shot.

 

I still think I'd prefer a next Gen Shuttle but this is fine for now.  🙂

 

Cheers

 

 

Space X is very cool 🚀

 

Not sure about a Shuttle, next gen even, what were the running costs again? I guess now that they have made it possible to land and reuse boosters that would cut cost of course.

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🙂

 

Dunno, the Shuttle was probably a bridge too far but by now we really ought to be able to do Single Stage to Orbit repeatedly - I guess the privateers have to re-climb the ladder - the way they are going it probably will not take long   🙂

 

Cheers

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50 minutes ago, chrisg said:

Single Stage to Orbit

 

There are good reasons NOT to do SSTO: a) The Rocket Equation - all that empty rocket means you need to burn more fuel to get the payload into position; and b) atmospheric and vacuum engines have very different bells - running a vacuum engine in atmo can damage it (to destruction, potentially), and running an atmo engine in vacuo is a massive fuel-hog.

 

WRT to b): There is a thing called an aerospike, which automatically handles 'bell' variation by not having one, and letting air pressure do the work.  Trouble is, the spike part (aero spike) get incredibly hot, and melts without active cooling - which weighs a lot.  The end result is that the extra bs required to make it work, and extra fuel need to lift the thing, makes conventional engines a better deal.  At least until some miracle material turns up.

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Hmm,

 

It depends how you burn it Cybes.

 

The shuttle was not QUITE an SSTO, it needed dual solid fuel boosters and a big tank both of which compromised it but it took some very big loads to orbit, with basically late 60s/early 70s tech - we've been going backwards.

 

For some reason we have, almost, abandoned mixed fuel dual stage to orbit initiatives but it actually makes very good sense, use jets to get to altitude then let rockets take over - that is what Virgin Galactic and the Stratolaunch is all about.

 

It does not have the glamor of a big rocket launching into the heavens but who cares so long as we get there ?

 

Long term I want beanstalks but the catch 22 is you have to go up there and get the material to build one, from orbit to earth - I really do not care how we achieve that so long as we do but it is not going to come about with capsules.

 

Cheers

 

 

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1 hour ago, chrisg said:

...the catch 22 is you have to go up there and get the material to build one, from orbit to earth...

 

Build from, yes, but you don't have to source from there - it just makes more sense, assuming we can get orbital manufacturing figured out.

 

The real problem is that we don't yet have the materials. CNTs could mechanically handle it, but the longest to date is something like 1cm, and we'd need thousands of them over hundreds of kilometers.  That's far more orders of magnitude than can be called 'trivial', even by cosmologists.

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Beanstalk? hope this is not the space elevator idea, I think it is impractical and will not happen.

 

Happy to be proven wrong.

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🙂

 

Right now, as Cybes says, it is impractical because of the material physics, the numbers do not add up.

 

However we do not yet really know what we  can do with manufacturing in hard vacuum and micro gravity, I've a feeling there will be revelations when we get serious about that, possibly graphene or similar.

 

The concept has been around for quite a while and it is generally accepted that given material  of a suitable tensile strength the rest is" just" engineering on a big scale.

 

The trick is first establishing more than a foothold in space, which is what the ISS really is, we need to be living there, manufacturing in orbit,  possibly at one of the Lagrange points. To do that we need something better than capsules.

 

I wont link the Wiki article because they are on a "pop up and beg" drive again and I don't know about you but I've given more than enough, but it is apparent that the idea is very much alive. Only late last year the Japanese did an experiment in orbit of cable linking two cubesats, which is an early proof-of-concept for an elevator.

 

Daring to dream big is what took us to space in the first place now we need to set up residence, an elevator is in the long run by far the most economical way to do that.

 

It's worth noting that building one on Mars would be much simpler, then we could really go colonising  🙂

 

Cheers

 

 

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21 minutes ago, chrisg said:

It's worth noting that building one on Mars would be much simpler

 

One on the moon is possible right now, with only steel cables and current engineering. It would greatly facilitate using Luna as a mining and manufacturing base, too.

 

If such a thing ever happens it wont be NASA or ESA that does it.

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Yeah, I'm done with wiki due to those popups.

 

To survive on Mars will require either structures with 3m think walls, or go underground, and that's just for protection from radiation, then there are a bunch of other hurdles to any long term stays there.

 

What took us to the moon was the cold war.

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Hmm,

 

 That is true Cybes, both ways, exploiting the moon will almost certainly be a commercial endeavor. I'd tend to think a fairly simple accelerator on the surface to chuck some material into orbit and then build an elevator. Once done it becomes near zero cost to ship out material. the question then becomes what to do with it, I'm rather more in favor of habitats than cluttering up the earth but probably a bit of both. 🙂

 

With radiation the same can be said of most anywhere in space that is outside the earth's atmosphere Datafast although Mars is not TOO bad it does have a bit of atmosphere. Very long term we will probably be looking at terraforming the place. I intend to be here for a looong time, but I doubt that long.  🙂 In the very long term however I suggest it is inevitable that we overcome the hurdles and colonise the place.

 

In a pragmatic sense you are right, the Cold war encouraged the "me first" attitude that took us to the moon, perhaps sooner than we would otherwise have gone there but I suspect that eventually we would have gone anyway, we are curious creatures. The question really is if we are in much of a hurry to go back, we already know enough about the place to know that it is not a great deal of use apart from for building material and the advantages of low gravity but I'm more interested in the lagrange points.

 

It seems NASA are determined to go back though.

 

I'd rather we did other things in space with the money then when we do go back it would be a simple thing, not some massive endeavor. It reminds me of going to the South Pole, the first few people who tried did not succeed then the next did - just. When we went back again in the 50s it was in style, we drove there  🙂

 

Cheers

 

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Terraforming?

 

Originated in Science-Fiction and is a hypothetical.

 

Got 100,000 years spare?

 

Very long term indeed.

 

https://www.nasa.gov/press-release/goddard/2018/mars-terraforming

 

https://www.science20.com/robert_inventor/trouble_with_terraforming_mars-126407

 

Edit: I'm like the party pooper lately, I better ease up on the fact repeating crap, and just have some fun.

 

 

Edited by datafast69

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30 minutes ago, datafast69 said:

Very long term indeed

 

Totally agreed. That is not an option.  Especially not for Mars, sorry Chris - you'd have to drive KBOs into that dungball for decades just to get enough atmo and water, then wait for a century or two for it to stop being lava, then millenia for it to make soil, and then finally you get to start crafting an entire ecosphere.

 

As much as I prefer Elon's hairbrained enthusiasm, and despise Bezos as a human being, he's got the better idea: O'Neil cylinders.

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11 hours ago, datafast69 said:

I thought you lot called it Soccer 😎

 

Yes..........the other name for it was Wogball.

(Don't worry, I played it for over 20 years until I was suspended for 16 weeks for inciting a riot)

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Oh, using anything we have thought of doing thus far yeah, Mars would be a terrible candidate for any conventional "shake and bake" as in whack it with an asteroid or three and go away for a couple of millennia then see what you have.

 

But how about thinking outside the box ?

 

We strongly suspect that Mars has SOME water but no obvious life.

 

Somewhere in the next few decades we will become adept enough at gene structuring to develop an algae tailored to an arid environment such as Mars that could for example live on sand and excrete CO2. Seed the planet with that - better make sure you have an antidote, and let it multiply. Once the CO2 levels are high enough introduce another bug that we had better have invented by then that ingests CO2 and excretes oxygen and you have the beginnings of a planet.

 

It is still going to take several generations but not millennia.

 

In today's world I utterly agree with you Cybes, for all his bullshit Bezos does have a better near-term goal than Musk, but Musk is the better visionary.

 

Bio-engineering, provided you can turn off what you turn on, has much more promise than brute force for transforming an ecology.

 

Cheers

 

 

 

 

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1 hour ago, chrisg said:

live on sand and excrete CO2.

 

... Sand=SiO2.  So where's the carbon come from?  You could use microbes/nanoassemblers to perform that trick with Venus's plentiful atmosphere, seeding the temperate region of the sky and letting it descend as the place cools down... Over many centuries.  You'd still need to find something to do with all that sulfur and then import a few hundred million tonnes of water.

 

1 hour ago, chrisg said:

We strongly suspect that Mars has SOME water

 

We know absolutely that Mars has some water.  More than a swimming pool - less than one of the Great Lakes.  That is not enough for an ecosystem, but might be enough for a domed city - which you'd need anyway because there's no magnetic field to speak of, and no ozone layer, so there's more radiation than a radiology lab.

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🙂

 

Well, I was being careless, more water than we presently are certain of.

 

The "atmosphere" is already predominantly CO2 anyway so there is carbon there but the sand is not simple silica, its a mix of whatever the volcanoes have brought to the surface but that will include carbon.

 

Domes are pretty much a given I'd agree, it would be a very, very long time before there is enough ozone to cut down on the radiation and a magnetic field is a challenge...  🙂

 

Nothing is insurmountable though, if the building blocks are there then it's a case of shuffling them around.

 

Some people have suggested that we are not likely to find too many planets that are sitting in the Goldilocks zone anyway so most of our future probably does lie under domes, or in space.

 

It's all a thought experiment.

 

On balance I agree with you, and unfortunately with Bezos, we are better off in very large habitats and using the planets for material to build them but that does mean some of us will be spending time on the surfaces getting the materials. That is unless we get so smart with robotics that we can just send our machines but that particular possibility perturbs me rather. Men and women are explorers, we need to go there, not watch it on TV.

 

Cheers

 

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Hmm,

 

 I guess with the location of Bay of Plenty and the prevailing winds it ought not to be an issue, NZ is sort of used to this kind of thing. It could be a bit worrying if you are actually on the island though.

 

Cheers

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