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Source: (consider it)
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Thread: To Infinity & Beyond !
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Doublethink.
Ship's Foolwise Unperson
# 1984
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Posted
Now SABRE engines have past initial testing of their cooling systems - and we know about these. How long before we are star trek / the culture / living in Sky's Edge ? What do we need to do to get sustainably off planet ?
It *is* rocket science ...
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All political thinking for years past has been vitiated in the same way. People can foresee the future only when it coincides with their own wishes, and the most grossly obvious facts can be ignored when they are unwelcome. George Orwell
Posts: 19219 | From: Erehwon | Registered: Aug 2005
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Wesley J
Silly Shipmate
# 6075
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Posted
A universe-net bulletin board. I propose 'The Spaceship of Fools'.
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Be it as it may: Wesley J will stay. --- Euthanasia, that sounds good. An alpine neutral neighbourhood. Then back to Britain, all dressed in wood. Things were gonna get worse. (John Cooper Clarke)
Posts: 7354 | From: The Isles of Silly | Registered: May 2004
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Martin60
Shipmate
# 368
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Posted
Nowt. A total waste of time and money. Let's get it right here.
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Love wins
Posts: 17586 | From: Never Dobunni after all. Corieltauvi after all. Just moved to the capital. | Registered: Jun 2001
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The Machine Elf
Irregular polytope
# 1622
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Posted
It's cold and dark out there, and the distances are too far for rockets. Alan Bond's machines are for getting into orbit, not colonising the stars. You can't carry enough rocket fuel for a small mission to our nearest neighbours and a hybrid won't help past our atmosphere - the stars are more than 10,000,000,000,000 times further than SABRE's range.
There's also the problem of finding or creating habitable worlds. We only have ever found one, and only seem to be able to decrease its habitability by our actions.
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Elves of any kind are strange folk.
Posts: 1298 | From: the edge of the deep green sea | Registered: Oct 2001
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Adeodatus
Shipmate
# 4992
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Posted
I would counsel against going very far with space exploration until we learn to stop naming things after phallic symbols. While we still have that mentality, it's unlikely to end happily.
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"What is broken, repair with gold."
Posts: 9779 | From: Manchester | Registered: Sep 2003
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AberVicar
Mornington Star
# 16451
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Posted
The whole basis of the Star Trek model is that it has discovered how to create propulsion without the combustion of carbon-based fuels. The SABRE engine seems to be nothing but another way of doing what existing engines already do, rather than the sea-change that would be needed to move sustainably over many light years.
Even so, there is an episode in Series 7 of Next Generation called Force of Nature where it is demonstrated that warp technology has an irreversibly destructive effect on subspace. While this is clearly an early parable referring to the issue of greenhouse gases and climate change, it is a reminder that technological progress comes at a price.
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Before you diagnose yourself with depression or low self-esteem, make sure you are not, in fact, just surrounded by assholes.
Posts: 742 | From: Abertillery | Registered: May 2011
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ken
Ship's Roundhead
# 2460
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Posted
It might make getting into orbit cheaper, which is great, but the energy required to lift off the planet is still huge, so space travel remains a minority pursuit in all likely scenarios.
The only real exceptions to that are if we discover some totally new physics to get round gravity, which probably won't happen, or else if we build a space elevator, which is even less likely.
I imagine that there will be serious commercial explotation of solar system resources in the future, but it might be a long time. And the stuff needed to do it will be built off earth not launched from earth. There might even one day be largish populations of humans off earth - though if it ever happens most of them will have been born off earth because its too expensive to leave. But not for a long time. As Charlie Stross pointed out years ago, there is nowhere in the rest of the solar system anywhere nearly as hospitable to human life as the Gobi Desert, or Antartica, or the deep oceans. And how many mega-cities do we build there? (Read that link if you can - its good stuff, and unlike most blogs the comments are almost all relevant and mostly interesting)
Yes, I think some sort of space-based industry, and maybe even human habitats, will happen one day. It ought to happen. Its a great idea. But it doesn't solve our problems here. If we want to live in peace and prosperity and health we need to sort ourselves out on Earth.
And even if we do have people living in space or on other planets that just gives us the one solar system. Everywhere else remains out of all realistic reach. (Well, except for, hmmm.....)
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Ken
L’amor che move il sole e l’altre stelle.
Posts: 39579 | From: London | Registered: Mar 2002
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Lietuvos Sv. Kazimieras
Shipmate
# 11274
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Posted
I understand that this is not what the OP is asking or addressing, but my view is that if it is our species' destiny to migrate to other planets, it will happen. I also realise that is simply a tautology. However, if we manage not to destroy our own planet over the next couple of centuries, I believe we might well succeed in developing the necessary technologies to actualise what is presently science fiction. I always thought it unfortunate that Star Trek didn't portray the Eucharist being celebrated in deep space; we already have a suitable liturgy for that context.
Posts: 7328 | From: Delaware | Registered: Apr 2006
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que sais-je
Shipmate
# 17185
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Posted
quote:
Originally posted by Adeodatus:
I would counsel against going very far with space exploration until we learn to stop naming things after phallic symbols. While we still have that mentality, it's unlikely to end happily.
Maybe a move away from phallic shaped rockets would be a good start. Are star gates the way forward?
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"controversies, disputes, and argumentations, both in philosophy and in divinity, if they meet with discreet and peaceable natures, do not infringe the laws of charity" (Thomas Browne)
Posts: 794 | From: here or there | Registered: Jun 2012
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Doublethink.
Ship's Foolwise Unperson
# 1984
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Posted
So space elevator, what would that require ?
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All political thinking for years past has been vitiated in the same way. People can foresee the future only when it coincides with their own wishes, and the most grossly obvious facts can be ignored when they are unwelcome. George Orwell
Posts: 19219 | From: Erehwon | Registered: Aug 2005
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Doublethink.
Ship's Foolwise Unperson
# 1984
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Posted
<tangent>
We could go for clitorally shaped rockets, but they might be less aerodynamic. (Which might not matter outside the atmosphere.)
</tangent>
[ 02. December 2012, 18:18: Message edited by: Doublethink ]
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All political thinking for years past has been vitiated in the same way. People can foresee the future only when it coincides with their own wishes, and the most grossly obvious facts can be ignored when they are unwelcome. George Orwell
Posts: 19219 | From: Erehwon | Registered: Aug 2005
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Eutychus
From the edge
# 3081
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Posted
quote:
Originally posted by Doublethink:
So space elevator, what would that require ?
As far as I can tell, the biggest obstacle is making an elevator cable that is strong enough not to fail under its own weight given the length, which I think is the distance to geostationary orbit times two. Carbon nanotubes are currently being explored, but for now are still several degrees of mangitude too heavy.
These problems look depressing, but they are not nearly as depressing as the fuel-to-ship ratio. For a brief and fun overview of this issue, see here.
I'm just glad to be old enough to recall the moon landings, and sorry that it seems unlikely that any of my kids will see anything so inspiring in that realm.
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Let's remember that we are to build the Kingdom of God, not drive people away - pastor Frank Pomeroy
Posts: 17944 | From: 528491 | Registered: Jul 2002
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Doublethink.
Ship's Foolwise Unperson
# 1984
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Posted
Hmm, wiki suggests maybe grapheme for a tether - now I know we have that.
[ 02. December 2012, 21:09: Message edited by: Doublethink ]
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All political thinking for years past has been vitiated in the same way. People can foresee the future only when it coincides with their own wishes, and the most grossly obvious facts can be ignored when they are unwelcome. George Orwell
Posts: 19219 | From: Erehwon | Registered: Aug 2005
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IngoB
Sentire cum Ecclesia
# 8700
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Posted
quote:
Originally posted by Lietuvos Sv. Kazimieras:
However, if we manage not to destroy our own planet over the next couple of centuries, I believe we might well succeed in developing the necessary technologies to actualise what is presently science fiction.
Without truly new physics - and new physics, not new engineering - we will not make it to the stars. Well, maybe to a few using generation ships, but you can totally forget anything like Star Trek.
quote:
Originally posted by Lietuvos Sv. Kazimieras:
I always thought it unfortunate that Star Trek didn't portray the Eucharist being celebrated in deep space; we already have a suitable liturgy for that context.
Uhh, what would have to be different from now for a deep space Eucharist?
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They’ll have me whipp’d for speaking true; thou’lt have me whipp’d for lying; and sometimes I am whipp’d for holding my peace. - The Fool in King Lear
Posts: 12010 | From: Gone fishing | Registered: Oct 2004
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ken
Ship's Roundhead
# 2460
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Posted
quote:
Originally posted by Doublethink:
So space elevator, what would that require ?
1) design a material about twice as strong as the strongest ones we know of. And unfortunately slightly stronger than the theoretical maximum strength of known materials made out of carbon - which is not to say there aren't other ways of making stuff stonger than that.
2) either make about a million (*) tons of the stuff and transport it to orbit (requiring far more old-fashioned rocket-type space launches than ever before) or else find a way to make the stuff in space (whiich means you need a large-scale manuafacturing economy off earth already, whiuch is the point of the excercise)
3) capture a medium-sized asteroid and put it in Earth orbit. Which is slightly scarier than capturing an angry elephant and putting it your back garden. If we develop ways to move those things around we want to get them further from us, not closer.
4) out in space make the strong stuff into a giant and very narrowly tapering cone about a metre across at the sharp end and maybe fifty metres across at the other end
5) tie the blunt end to the asteroid. Very tightly.
6) very carefully move the sharp end down to earth and tie it to a high tower (like about five miles high) or a big mountain. Not quiet as tightly as the other end is tied to the asteroid.
7) Turn the asteroid into an immense space station. It probably will be already by this time.
There are political and economic problems. The main one is that this is going to take a huge part of the industrial investment of the whole world to do, which has to come from rich countries and big governments, but the earth station has to be located very near the equator - ideally in an underpopulated location near the sea and on top of a big mountain. (Kenya or Tanzania are the linely best bets for verious reasons) Are North American and European ans East Asian governments going to want to send all that money to such a place? Why not, say, build a network of super-fast railways connecting their own cities up for a lot less money? Or building
There are other problems. One is, that if it breaks you want to pray that it breaks as near the earth end as possible, because everything above the break is going to fly away (just imagine all that expensive investment drifting off into space!) and everything t below the break is going to come down, and quite possibly very hard indeed. Maybe hard enough to break holes in the earth's crust and make some new volcanoes. The equator wouldn't be ain imaginary line on maps any more it would be a real one, visible from orbit, and surrounded by dead people., ruined cities, and burned forests. Whoops.
Oh, and the bit that drifts off into space is very likely to go into Earth orbit (and if it doesn't then it'll go into solar orbit) and sooner or later its going to come back and you really don't want it to come too close because then we're into mass extinction mode.
On the other hand, we could build such a thing on the Moon with existing technology. Though the Moon is quite easy to take off from anyway, and a big lift there doesn't hellp get from hjere to there much. And if we wanted a non-rocket way of getting lots of stuff from the moon to earth big electrical mass-drivers make more sense. You'd have to catch the stuff in a sort of net on a space station in low Earth orbit. Which would then rise into a slightly higher orbit. In fact that's a better destination than Earth. The Moon is mostly made of quite normal rocks. We have lots of those alreaady. But for building a really big space station the Moon might be a better source of raw material because the gravity is so much less.
A space elevator on Mars is at about the limit of what seems feasible to be honest. And the only point of building one there would be if Mars was already full of people and stuff - and that seems unlikely without cheap space travel...
To colonise space or other planets we need lotss of infrastructure first. This isn't like Christopher Columbus or Leif Erikson or the Pilgrim Fathers . Its more as if the Europeans had had to wait until the Interstate Highway system was built before sending any settlers - they'd still be waiting.
(*) That is a metaphorical "million". The exact number depends on all sorts of things and the sums are too hard for me to do. Estimates vary from about 20,000 tons (which seems fair enough except that that assumes materials five or ten times stronger than have so far been discovered, and would only be the thickness of a wire at the bottom end) to billions of tons (and if we could do that, why bother to go to the moon, we could build our own one)
[ 03. December 2012, 12:40: Message edited by: ken ]
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Ken
L’amor che move il sole e l’altre stelle.
Posts: 39579 | From: London | Registered: Mar 2002
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Eutychus
From the edge
# 3081
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Posted
OK. Instead, let's go for the Launch Loop using Capture Rail technology.
For more discussion, see here. The site linked to in the first two links above is apparently run by one of the contributors to that thread.
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Let's remember that we are to build the Kingdom of God, not drive people away - pastor Frank Pomeroy
Posts: 17944 | From: 528491 | Registered: Jul 2002
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IngoB
Sentire cum Ecclesia
# 8700
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Posted
Another problem, for those who think that new physics is the answer: any new physics that can be exploited technologically, will get exploited hardest and fastest for ... weapons. Count on at least a decade or two before civilians get access to the hot new physics gear.
Now, what would a creative military do with something like a teleport or a warp drive? Or Al Qaeda? Or for that matter, what would the average nasty human being do?
Pray that the end of physics has come, and that we will be stuck on earth forever. We have scraped through the invention of nuclear technology alive (probably...). If we invent stuff that can puncture spacetime, we will just all die in highly spectacular ways.
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They’ll have me whipp’d for speaking true; thou’lt have me whipp’d for lying; and sometimes I am whipp’d for holding my peace. - The Fool in King Lear
Posts: 12010 | From: Gone fishing | Registered: Oct 2004
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Jane R
Shipmate
# 331
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Posted
quote:
Uhh, what would have to be different from now for a deep space Eucharist?
<imagines the mess an open chalice could make in zero gravity> I suppose it depends how high a view you have of the sacraments...
Genuflecting might be a challenge, too.
Posts: 3958 | From: Jorvik | Registered: May 2001
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IngoB
Sentire cum Ecclesia
# 8700
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Posted
Zero G? Surely there will be both artificial gravity and radiation shielding. Or we will all be really unwell after a few years...
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They’ll have me whipp’d for speaking true; thou’lt have me whipp’d for lying; and sometimes I am whipp’d for holding my peace. - The Fool in King Lear
Posts: 12010 | From: Gone fishing | Registered: Oct 2004
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ken
Ship's Roundhead
# 2460
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Posted
quote:
Originally posted by Eutychus:
OK. Instead, let's go for the Launch Loop using Capture Rail technology.
For more discussion, see here. The site linked to in the first two links above is apparently run by one of the contributors to that thread.
Even scarier than the elevator!
It took about five web pages to find what they meant by the word "rotor". When I finally got to it I decided I didn't want one anywhere near a planet with my friends on it.
Executive summary - half a million iron bars, flying through a narrow pipe fifteen times faster than a speeding bullet and when they get to the end they have to be turned round by a giant magnestic loop and sent back the otehr way at the same speed.
Political reason no-one is every likely to build one: any government with a navy won't want to share an ocean with this thing. Its basically a machine gun the size of a small planet. And very, very, precisely aimable.
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Ken
L’amor che move il sole e l’altre stelle.
Posts: 39579 | From: London | Registered: Mar 2002
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