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Post by And Kevin 2024 on May 15, 2023 0:48:37 GMT
It may be the final frontier, but it's depressingly gob-smackingly big. It takes three days just to get to the Moon, just 250.000 miles away! We simply do not really as yet have a practical method of going fast enough to make it a sensible idea to even go in person to visit the planets in our own Solar System. We still use giant fireworks. It will take at least 15 days to get to Mars, the closest planet, depending on how close it is at the time. Not to mention it would be a one-way trip for humans. But some still want to go ... Enter Science Fiction. Stories within that sphere have had to 'invent' faster-than-light, which is still too slow, so other methods of travel too, in order to get around within a practical time. There is one story, made in to a few TV series, The Expanse, that has us at least populating our own Solar System, in a few hundred years time! In that it's not mentioned how fast they can travel, and how long it takes, but it fortunately, to make it far more interesting, it does not seem to take long, but nowhere near FTL. In SF, they often attempt to describe whatever currently very theoretical method they use, but not how it's achieved. In films and TV an engine is often shown, but the power needed to, say, create a wormhole, would be so astronomical it's bordering on Science Fantasy. And how would you direct the exit point unless you had already been there? Scientists do mention that we are seriously held back by not having a small ultimately powerful, well, source of power. An AA battery with the power of a sun. Stargate 'cheats' to get around it. They find wormhole generators all over the galaxy (and in to others!) that don't seem to use a power-source, created by some almost god-like beings millions of years ago, and left abandoned. And two on Earth in fact. How very convenient. The future is a long place, so there's no real knowing if or when these theoretical methods could be put in to practice. But fiction writers can dream can they not?
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Post by Retread-Retired-Cameron on May 15, 2023 16:48:41 GMT
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Post by And Kevin 2024 on May 15, 2023 23:11:15 GMT
"The Expanse" series of books indicates it takes weeks to cover interplanetary distances, utilizing what appears to be a fusion reactor and propellant. No doubt, but I have not read the books. In the TV series they don't bother to say what they use. Although I do like that they have to turn their engines to face backwards before their destination to slow down. I seem to recall some actual scientist saying that no matter how fast or how far, half the journey would be spent slowing down.Project Orion is a craft which can be built with current technology which could reach ~3.3% Light Speed. There is a treaty in place preventing it from being built due to the prohibition of nuclear explosions in space. en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)Yes, I know of that. Decades ago, before radiation was a worry. And of course it exploding on the launchpad. It would still take at least 133 years to reach the nearest star to ours though (and of course very hard and slow to communicate with.) Still a depressing thought. Some of the things up there do use tiny nuclear power devices though.Direct Fusion Drive [currently being worked on] would be faster than chemical rockets since the burn can go on longer, though thrust would be much lower than the Project Orion design. en.wikipedia.org/wiki/Direct_Fusion_DriveStill too slow. And are both methods not very heavy? There is also research ongoing regarding human hibernation. spaceref.com/newspace-and-tech/research-into-human-hibernation-for-long-distance-spaceflight/ www.iflscience.com/can-humans-learn-to-hibernate-67768Indeed. All SF stuff but still impractical, unless they don't intend returning. And it's jolly dangerous. Even creatures that have been doing it for 1000s of years only do it for a few months at a time. www.ox.ac.uk/research/could-humans-hibernate-0For now it's all about getting the engineering done and workable. Well, err yes. There's so many things that come under those categories. But often it's about steps in development. Somethings cannot be invented until other things have been invented first. Or discovered. Such as this example electricityforum.com/a-timeline-of-history-of-electricity It's a shame people and countries don't cooperate more, rather than only thinking of the commercial or war aspects. Space is a good example of such. So many countries and commercial enterprises going their own way, often duplicating efforts: and costs.
Thank goodness at least SF takes us there.
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Post by BlueAndGold on May 16, 2023 1:35:37 GMT
In the real universe, maintaining steady acceleration is the key to covering distance. If you do the math, you will find that if you maintain just one G, Pluto is just two weeks away - not the years it takes coasting at a measly 50K MPH like Voyager, et al.
In other words, if you can maintain 8 G’s for 3 hours you can be a long, long, way from here – like 2.8 million miles!
The reason most current spacecraft don’t use constant acceleration is because our clunky, inefficient rockets eat too much fuel and can’t carry that much fuel. However, most current deep-space missions now include small ion drives that do provide steady acceleration, but they are not very powerful - thrust measured in grams and ounces. It’s coming though. Many new-generation satellites are being equipped with ion drives for changing/maintaining orbit. Our heroes in the future [of SPACE: An Odyssey in Rhyme] are blessed to have atomic torch engines which burn any mass for fuel at near 100% efficiency and can maintain thrust for weeks at a time for the long hauls. Big ships have multiple torches. Most ships have archaic rockets as well for when they need a lot of thrust NOW.
But nobody can take 8 G’s for 3 hours, so we run at 2 G’s and put up with saggy boobs instead of crushed lungs and spines. And yes, you have to turn around and decelerate for part of the trip to slow down too.
In the real universe, this technology is not far off.
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Post by Retread-Retired-Cameron on May 16, 2023 18:31:53 GMT
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Post by And Kevin 2024 on May 17, 2023 23:15:33 GMT
In the real universe, maintaining steady acceleration is the key to covering distance. If you do the math, you will find that if you maintain just one G, Pluto is just two weeks away - not the years it takes coasting at a measly 50K MPH like Voyager, et al.
I have no idea what you mean, maths or not. What do you mean travel at the speed of 1 gravity? Which is based on the 'pull' of the earth, down to the earth, and has a maximum speed does it not?
In other words, if you can maintain 8 G’s for 3 hours you can be a long, long, way from here – like 2.8 million miles!
Well, if you have an engine that can create the speed of light you would be much further away ... and potentially crushed unless you invent inertialess drive first.
The reason most current spacecraft don’t use constant acceleration is because our clunky, inefficient rockets eat too much fuel and can’t carry that much fuel. Indeed. Giant fireworks. Using a lot of fuel just to carry the fuel.However, most current deep-space missions now include small ion drives that do provide steady acceleration, but they are not very powerful - thrust measured in grams and ounces. It’s coming though. Many new-generation satellites are being equipped with ion drives for changing/maintaining orbit. They use electricity. Current solar panels don't provide enough to power an ion engine of any great thrust. And the further one gets from the sun, the less it is. They would need a way of generating quite a lot of electricity to be practical, and fast, space engines.Our heroes in the future [of SPACE: An Odyssey in Rhyme] are blessed to have atomic torch engines which burn any mass for fuel at near 100% efficiency and can maintain thrust for weeks at a time for the long hauls. Big ships have multiple torches. Most ships have archaic rockets as well for when they need a lot of thrust NOW. Ah, SF ... Star Trek have engines that can travel up to the speed of light, very handy, beyond that they can generate warp drive, which I assume folds space. A very strange theory. Apparently they use dilithium as a fuel, whatever that is. I doubt it's the same in reality as it is in SF.
But nobody can take 8 G’s for 3 hours, so we run at 2 G’s and put up with saggy boobs instead of crushed lungs and spines. And yes, you have to turn around and decelerate for part of the trip to slow down too.
In the real universe, this technology is not far off.
If you take notice of SF, and even some scientists in the past, we would all have robot slaves by now, anti-gravity, colonies on Mars, oh, and zombies. SF should not include dates. And maybe neither should theorists.
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Post by And Kevin 2024 on May 17, 2023 23:20:06 GMT
Indeed. Taking our current manned space launches in to account, they have to restrict the acceleration on take-off, and the time it takes to get out in to space, so as not to kill the astronauts. One of the reasons they want to build bases on the Moon is it's handier to take off from. Less gravity, and no atmosphere.
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Post by Retread-Retired-Cameron on May 18, 2023 0:51:02 GMT
Indeed. Taking our current manned space launches in to account, they have to restrict the acceleration on take-off, and the time it takes to get out in to space, so as not to kill the astronauts. One of the reasons they want to build bases on the Moon is it's handier to take off from. Less gravity, and no atmosphere. Hmmm, I suspect the English Space Agency did much better than the US Space Agency.
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Post by And Kevin 2024 on May 18, 2023 23:54:58 GMT
"Hmmm, I suspect the English Space Agency did much better than the US Space Agency." Pretty much all they do is cheer on and 'support' those who actually do the physical stuff. These are the people here who actually do things > www.esa.int/ including pushing satellites in to space for the USA. And these build a lot of stuff > en.wikipedia.org/wiki/Airbus. While Richard Branson (Virgin) plays at ideas for the rich.
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Post by And Kevin 2024 on May 18, 2023 23:59:59 GMT
There's these as well >>> starchaser.co.uk/ based not far from me, in the centre of a town! But they seem to be just enthusiastic amateurs who never achieve much, but they have been doing it for years!
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Post by Retread-Retired-Cameron on May 19, 2023 14:34:27 GMT
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Post by And Kevin 2024 on May 19, 2023 22:43:20 GMT
Who puts stuff up there often depends on if it is commercial, scientific, or military. Musk seems to be concentrating on getting a bus to the Moon and getting people living on Mars. I expect the spin off from that will be travel to the ISS rather than his company just being a grocery delivery and rubbish removal service for it. Having to use Russia to carry people to and from it is a bit of an embarrassment, especially now.
Is it not time someone built a shuttle? They do not have to be as big as the old ones.
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Post by Retread-Retired-Cameron on May 20, 2023 17:00:49 GMT
The space shuttle was risky from inception, in part due to the requirements for aerodynamic flight and space flight being very different. Add in issues involved with using Solid Rocket Boosters and the flying bricks weren't nearly as safe nor as cost effective as imagined.
In essence riding into space at present is akin to sitting on top of a really large bomb and hoping the explosion is controlled enough to get you into orbit alive.
SpaceX is beginning to carry crew to the space station. Musk's SpaceX has received a lot of government funding and subsidies to the tune of billions while his original investment was reported as $100,000,000.
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Post by And Kevin 2024 on May 20, 2023 23:24:42 GMT
The space shuttle was risky from inception, in part due to the requirements for aerodynamic flight and space flight being very different. All the same, it did some very handy things. Just imagine what use the Hubble would have been if they could not have gone up and fitted it with glasses. Currently there's nothing that can go up and mend things. Add in issues involved with using Solid Rocket Boosters and the flying bricks weren't nearly as safe nor as cost effective as imagined. I doubt anyone thought they were cost effective. But it's the norm that quotes turn out to be rough estimates. However the concept is far from forgotten. www.bbc.com/future/article/20210121-spaceplanes-the-return-of-the-reuseable-spacecraft and the very peculiar Mr Musk has brought the cost of spaceflight don.In essence riding into space at present is akin to sitting on top of a really large bomb and hoping the explosion is controlled enough to get you into orbit alive. More akin to a huge firework rocket I would have thought. Bombs are made to explode.SpaceX is beginning to carry crew to the space station. Musk's SpaceX has received a lot of government funding and subsidies to the tune of billions while his original investment was reported as $100,000,000. That's normal also. Just one example globalnews.ca/news/3773916/bombardier-boeing-subsidies/ and Musk 'only' invested $100,000,000? what a tight arse. But SpaceX does continue to spend money. www.cnbc.com/2023/04/29/elon-musk-spacexs-starship-costing-about-2-billion-this-year.html
But even so, many things to be found in SF have still not come true. Although people do still experiment and set goals www.nasa.gov/pdf/503466main_space_tech_grand_challenges_12_02_10.pdf and at least some are making money from space-travel, etc. hbr.org/2021/02/the-commercial-space-age-is-here
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Post by And Kevin 2024 on May 20, 2023 23:26:26 GMT
I just wish I was not born so long ago.
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