Moontanman

Wouldn't that depend in part on how fast your slow boat was going? To people who live inside space habitats the trip would just be life as usual, so the speed could be quite low. The time of travel would be very long of course but if you used the same amount of energy to slow down as you used to speed up... Then again this could seem trivial to beings with much longer life spans than ours, or technology that allows them to spend most of the time in hibernation, combine that with long life spans... Technology is a wonderful thing. Also i can see a system similar to staged rockets, the engine could be dropped after the habitat hits a certain speed, things like magnetic sails could be used to decelerate, or carry a second stage capable of slowing down in conjunction with mag sails. I am sure that thousands of years in the future technology could be somewhat more advanced than today and be capable of things like antimatter drives or fusion drives or more likely something we haven't thought of yet. I'm not sure how that could explain the Fermi paradox, are you suggesting that most planets are too big to escape from? Teapot orbiting jupiter? I have not suggested such a thing, only logical extensions of current technology not physics breaking Clark Tech! I'm not sure I understand this, things like Ion drives use much less fuel to do the same thing as a chemical rocket, other methods like fusion or antimatter could hypothetically be even more efficient, wouldn't not requiring high speeds be another way to requre less fuel?

Swanson, I honestly do not understand what you are talking about, your statement seem to be a blanket statement without any nuance. Please elaborate.

I agree the balance may indeed be fine, maybe there are planets that require nuclear power to escape... my idea of colonizing space happens after the the beings escape their planet. In fact you have hit upon why a space faring civilization might want to avoid planets. coming and going from a Earth sized planet require enormous amounts of energy, it would be much easier to travel between space colonies than between planets. Once a civilization begins to colonize via space habitats the game changes from going in and out of deep gravity wells to using things like ion drive or hall thrusters or maybe things we do not see happening yet. As the integrity of space colonies gets better and better at total recycling, probably won't ever be 100%, the idea of spanning space in the home you already live in becomes much more attractive to certain types of people at least. It also make choosing a goal much easier since you are not looking for habitable planets.

I agree, but how do these things prohibit star travel? There are ways to star travel without violating the laws of physics. Slow boats are an example, we might not be able to do it now but it's mostly engineering problems not the laws of nature. I don't think planets are necessary, in fact I doubt planets would be a factor at all in any equation. Planets are deep gravity wells, why bother when space habitats made from debrei like asteroids and kuiper belt like objects can be used to build space habitats. An inhabited planets would be at best a curiosity.

You make a good point, back then science wasn't what we consider science, I apologize for suggesting otherwise. But as others have said, Lord Kelvin evidently being a good example, what passed for science or maybe more appropriately authority in the past has made some assertions that simply didn't hold up. It's easy to point back and say they were wrong... will it be as easy to point back at us from 2 or 3 hundred years and consider what we have as not real science? I wouldn't be surprised if it was... But I am not suggesting that aliens are visiting due to this, I am suggesting that making assertions of fact about things that can change is not a good idea. I have backed far away from UFOs are run amuck in our skies... It was silly to assume such things without better evidence, how ever I see no reason to assume that because we can't currently star travel doesn't mean that other life forms cannot. I have no idea what aliens would be like or capable of, anything we say is simply speculation. Even if it's based on what we know it is still subject to the limitations of what we know currently. I have seen some ideas from futurists that suggest a lot of what some say is impossible is simply very difficult for life forms like us to accomplish, other life forms might very well find ways around the biological problems that we simply cannot do and maybe even will not do. These kind of conversations inevitably run up against speculation, speculation can make a great conversation, but it is still speculation and must be tempered by evidence. I think that colonization of our own solar system might eventually result in technology that would allow star travel, slow boats in my estimation are most probable but again that is just my opinion. Colonization of our own solar system is, in my mind at least, paramount for the survival of humanity in the long term. I see no reason to seriously pursue star travel when the solar system is available for our exploitation. I would think we'll be busy near our own star for thousands if not millions of years, if that eventually leads to space habitats capable of slow boating to other star systems then we will probably do it. But I see no driving force to get to another star anytime soon. Personally I can conceive of ways to star travel that are not impossible, maybe not particularly probable, but such conversations are still just thought experiments of ifs, and maybes projected by us. Once you start speculating science starts retreating into the distance. "If frogs had wings" And remember Fusion Power is just 20 years away!

@exchemist The science of the day? I have heard recently over and over that interstellar travel is impossible here on this site, there is nothing in physics that supports that, in Jefferson's day and many years before, rocks falling from the sky was explained away by saying that such rocks had to be blasted out of the earth by volcanoes or some other "earthly" explanation. Meteorite displays were removed from museums because the consensus was that rocks could not fall from the sky. That consensus can be wrong and I am for one glad it can be wrong, it's how we progress. Pasteur showed that life did not arise spontaneously, he had no explanation for how life came to be only that life came from life. All of these things in their time were dismissed by the "scientific consensus" of the time, not because the people were stupid or uneducated but because they didn't have the knowledge to say otherwise. Right now, we really don't know enough to say what is and what is not possible, we can only continue to further science as find new paths to knowledge. We are all hamstrung by what we currently know, it just is what it is, if you look deep into what is being pursued in science and engineering there are many ongoing efforts to break past what is currently scientific consensus. Not in huge showy mind bending ways but in the slow increments that has always been the lifeblood of science. Very few scientists have the "I have become death destroyer of worlds" moments. Trying to project our current understanding into the future are just as likely to be as accurate as the scientists or philosophers of centuries or even decades ago projecting their understanding onto our time. Science breaks barriers by building on the works of others. I am just not so sure that our current consensus of science is going to ever be the final consensus. At the time they were made they were considered as scientific as it got at the time. Science now is not the same as the science that rejected dinosaurs, or that Humans are related to apes. They were scientists they just weren't as advanced as they are today. Kelvin explained his reasoning; it suffered from not accounting for convection and not knowing about radioactivity. Scientific means one can critique the analysis and point out errors. If that analysis is not present, it’s not scientific. It’s a guess, or an appeal to conventional wisdom. You are correct, No, Dr. William H. Pickering (the JPL director) never said that travel to the moon was unlikely; in fact, he actively built the spacecraft that made it possible. [1, 2] Confusion around this claim typically stems from two main sources: a mix-up with a completely different scientist, or a historical quote about airplanes being misremembered as being about space travel. [1] 1. The Confusion with Professor A.W. Bickerton The famous skeptical quote often floating around the internet—"This foolish idea of shooting at the moon is an example of the absurd length to which vicious specialization will carry scientists..."—was actually written by a New Zealand physicist named Professor A.W. Bickerton in 1926. Because Dr. William Pickering was also a famous scientist from New Zealand, internet trivia lists and quote repositories occasionally misattribute Bickerton's pessimistic quote to Pickering 2. A Mix-Up with a Different "William Pickering" There was an older, unrelated Harvard astronomer named William Henry Pickering (1858–1938). While he spent his life obsessively mapping the moon (and incorrectly believing it was covered in changing vegetation and insects), he did make a famously wrong prediction in 1910 regarding aviation: [1, 2, 3, 4] Because this older William Pickering claimed commercial flight was a fantasy, his quotes are frequently lumped into "bad historical predictions" lists, which people later mistake as comments about space exploration. [1, 2]

All of them are real but I have not quoted them exactly, Dr. Dionysius Lardner in the 1820s is supposed to have said humans cannot travel faster than 40 mph. Lord Kelvin said the Earth was a few million years old This is just one claim about travel to the moon " Dr. William Pickering Director of the Jet Propulsion Laboratory (JPL), he famously declared in 1957 that the idea of sending a man to the moon was "absurd" and that it would not happen in the foreseeable future. [1]" "The Famous Quote Origin While Aristotle provided the ancient foundation, the most famous modern quote on the topic is often attributed to the third U.S. President, Thomas Jefferson. [1, 2] When two Yale professors (Benjamin Silliman and James Kingsley) visited him to report a meteorite fall in Weston, Connecticut, Jefferson is famously reputed to have said:" "The concept that life cannot arise naturally from non-living matter—known historically as spontaneous generation—was first challenged scientifically by Louis Pasteur in the 1860s. He disproved the ancient belief, leading to the Law of Biogenesis: the scientific principle that life only arises from pre-existing life. [1, 2, 3] Several historical and modern figures are closely associated with arguing against the natural origin of life: Aristotle (c. 300 BC): He was the earliest to document and popularize the theory of spontaneous generation (e.g., believing fleas and maggots arose naturally from dust or mud), setting up the debate that later thinkers had to refute. [1, 2, 3] Louis Pasteur (1859): Conducted famous experiments using swan-neck flasks that conclusively proved even microscopic organisms could not arise spontaneously in sterilized broth, famously asserting "life only comes from life". [1, 2, 3]" I apologise for the weird quotes, some kind of AI crap came with my new computer and it's driving me nuts.

All of them.

This dilemma reminds me of proclamations made in the early days of science, going faster than a hundred mph or so is impossible, the earth cannot be more than a few million years old, going to the moon is impossible, life cannot arise naturally, rocks cannot fall from the sky, the ideas they thought to be nonsense were often just a lack of information. I am not willing to say what is possible or not, I know a lot of science based speculation goes way to far for us really take it seriously... but rocks do fall from the sky, people can travel at speeds long thought to be impossible, the earth is 4.6 billion years old, life did indeed arise here, and we have visited the moon. Saying something cannot be done is a good way to be wrong but one thing is sure... assuming something is impossible is a good way to make sure it is never pursued seriously.

I think it helps quite a bit, a robotic craft doesn't have to have life support running for thousands of years, all it needs is the ability to find resources in another planetary system and use them to build... it could be quite small compared to a traveling colony of living humans, a self replicating Von Neumann type probe. I think a lot of this depends on exactly what we are talking about. Are we talking about sending a live human to another star system with that person's lifetime? A slow colony ship to another star? An unmanned probe? I think the most obvious way would be a slow colonization of a stellar system via artificial habitats and then venturing outward as the technology matures maybe snagging interstellar comets as they pass the solar system then possibly onto other objects in interstellar space hopping off when they pass other star systems. Once humans get used to inhabiting habitats in space and improve the technology whether or not a star has an habitable planet becomes meaningless, debris becomes the goal not planets.

We have the occasional thread on alleged aliens but nobody ever seems willing to tackle the physics and engineering discussion of how they got here Interstellar travel would indeed be a challenge but I see no reason to assume it's not possible. From robotic craft carrying data that could be used to reconstruct living beings upon arrival to long term space habitat travel I would hesitate to claim it can't be done. I would think a slow colonization of places like Keiper belts and oort clouds being used as a source of raw materials to build artificial habitats capable of slowly traveling from one star to another to using space objects similar to kuiper belt objects which are thought to occur in interstellar space but if not you could take a chunk of a kuiper belt object along with you to use as a store of raw materials for the trip. If small comet like objects exist in interstellar space they could be used as spepping stones from one star to another. I would think that slowly spreading across space using these methods would be preferable to only looking for habitable planets and trying to travel directly to them from one star system to another. I would expect searching for habitable planets and then taking off to colonise them would be very difficult but slowly spreading from one star system to another using small bodies as resources makes much more sense. In fact I have doubts that planets would be desirable at all, deep gravity wells, possible disease from alien microbes and native life forms would make the controlled conditions of a space habitats more desirable and would also make nearly every star colonisable whether it has planets or not. Why are you assuming chemical rockets? What about other more efficient means of propulsion https://en.wikipedia.org/wiki/Spacecraft_propulsion Propulsion technologySpacecraft propulsion technology can be of several types, such as chemical, electric or nuclear. They are distinguished based on the physics of the propulsion system and how thrust is generated. Other experimental and more theoretical types are also included, depending on their technical maturity. Additionally, there may be credible meritorious in-space propulsion concepts not foreseen or reviewed at the time of publication, and which may be shown to be beneficial to future mission applications.[37] Almost all types are reaction engines, which produce thrust by expelling reaction mass, in accordance with Newton's third law of motion.[38][39][40] Examples include jet engines, rocket engines, pump-jet, and more uncommon variations such as Hall–effect thrusters, ion drives, mass drivers, and nuclear pulse propulsion.[41] Recently I've seen a fusion engine that (supposedly) can be strapped to another space craft and reused (I'm not really sure how serious this one is) https://pulsarfusion.com/sunbird-fusion-propulsion/ The fact remains that technology is advancing and I doubt that chemical rockets will be the limiting factor. One more https://www.msn.com/en-us/news/other/nasa-tests-record-power-lithium-plasma-engine-for-mars-travel/gm-GMA58E3587

Yeah, maybe Trump will release the bigfoot files soon, or the Fae Plan... 🤩

Finally!

Industrial disease was one of my favs as well, I always liked to play it on the way to work at midnight!