Is interstellar travel possible?

[Airbrush]

Interstellar travel is just not possible for humans in my opinion.

 

Interstellar travel is just too difficult and there are too many dangers for such a project to be safely accomplished.

 

My source for this is:

 

https://www.scientificamerican.com/article/interstellar-travel-as-delusional-fantasy-excerpt/#

 

I read parts of your article and it is interesting.

 

HUMAN interstellar travel is a long way off, but sending small probes at high speeds to many nearby stars with Earth-like planets is not so far-fetched. Problem is it may be hundreds of years before we get news back from such probes. But isn't it worth it?

[KipIngram]

HUMAN interstellar travel is a long way off, but sending small probes at high speeds to many nearby stars with Earth-like planets is not so far-fetched. Problem is it may be hundreds of years before we get news back from such probes. But isn't it worth it?

 

I read an overview of that idea a while back and it did sound really intriguing. I do feel that some things are worth doing just to do them - to "achieve that."

 

Regarding human interstellar travel, I'd think that a multi-generational vessel would be possible. I can't think of any overt technological barrier. I suspect, though, that the odds of success of such a mission would be very low - so many things that could go wrong. And moreover, we don't even have any certainty about a place to send anyone, do we?

 

That would be the reason for the small probes - the hope of identifying a planet, not already claimed, that would support worthwhile human life.

[Ken Fabian]

There are proposals like "Breakthrough Starshot" - Postage stamp sized probes launched in large numbers by large laser arrays; I suspect optimism is the special magic ingredient that is expected to overcome all obstacles to make it actually work. I don't believe in magic. That unshakeable optimism is an almost universal characteristic of proposals to send manned or unmanned missions to other stars. This particular one would probably require the launch of a continuous series of probes that can act as communications relays; postage stamp sized probes are not likely to be able to transmit strongly enough to reach all the way. The energy requirement to launch even a <1g probe fast enough to reach Alpha or Proxima in 20 years is enormous; it better not be coal or gas plants providing it. We better have sorted out our emissions and energy and sustainability problems sorted out first - but the impacts on projects like this seem almost an irrelevance in the greater scheme of things.

 

I'm very dubious that any interstellar mission will be undertaken let alone succeed. I'm actually extremely dubious that any direct, non-stop mission will be capable of crossing between stars and still be functional at the end.

 

Whilst still extremely unlikely and difficult in other ways, but I think potentially possible, is humans reaching other stars very, very slowly - self supporting colonisation of deep space objects would allow human expansion that leap frogs from one to another, perhaps preferentially on a tangent towards another star, ultimately to see far distant descendants get within reach. Given that I don't think we will see self supporting colonies in space except as the unintended consequence of long lasting, large scale, economically successful exploitation of space resources by a wealthy, healthy Earth based economy - which can't happen without some extraordinary technological leaps that can make what is hugely difficult and expensive cheap and easy - I see nothing inevitable or even likely about it. There is no reason to expect technological leaps like that to be possible let alone count on it as inevitable.

Edited June 1, 2017 by Ken Fabian

[zapatos]

While interstellar travel will not be attempted in our life times there is nothing that makes it impossible. We've already been traveling on our spaceship for our entire lives.

[Airbrush]

The question is how many hundreds of years can humanity prosper, develop better technology, and avoid self-destruction, or asteroid impact, supervolcano, or other extinction level event, or even a solar event that returns us to pre-industrial times, to agriculture for survival. Forget about any missions to the stars for hundreds of years. How long can we avoid such a major event?

Edited June 1, 2017 by Airbrush

[KipIngram]

Quite a few *hundreds*, I'd imagine, since we've done so for many many thousands so far.

[zapatos]

The question is how many hundreds of years can humanity prosper, develop better technology, and avoid self-destruction, or asteroid impact, supervolcano, or other extinction level event, or even a solar event that returns us to pre-industrial times, to agriculture for survival. Forget about any missions to the stars for hundreds of years. How long can we avoid such a major event?

 

I'm confused. In your last post your question was "But isn't it worth it?". Why is that no longer pertinent?

[Airbrush]

 

I'm confused. In your last post your question was "But isn't it worth it?". Why is that no longer pertinent?

 

I still believe it is worthwhile for humans to TRY to explore beyond the solar system. For many decades to come, all we can know is from newer, better telescopes, such as TESS and the James Webb telescopes. Then probably a few generations of telescopes after that. Then in a hundred years or so, people may start to think about getting a close up look at a large number of nearby Earth-like planets. New, unimagined propulsion methods may be able to accelerate a multitude of small probes to a significant fraction of light speed. These probes that survive the voyage of 50 years or so would probably be fly-by missions taking lots of photos and scanning to send the info back to Earth, which would take maybe another 10 or 20 years for the info to travel at light speed home, maybe by relay as mentioned above. Could we be receiving the info within a few hundred years from now?

 

We may survive as a species for thousands of years, but humans are great at shooting themselves in the foot, e.g. WW1 and WW2. Or we can be sent back to a pre-industrial age by solar flare, and a "Waterworld" due to global warming. At that time a "space program" would be impossible.

Edited June 1, 2017 by Airbrush

[KipIngram]

We may survive as a species for thousands of years, but humans are great at shooting themselves in the foot, e.g. WW1 and WW2.

 

I think WW2 in particular was an example of us showing our ability to work together to solve a problem. Granted, the problem was of human origin, but it was dealt with. I'd more say the manner in which we dealt with the aftermath of WW1 showed a lack of wisdom - we made the German people ripe for the picking for a madman like Hitler.

[Airbrush]

Human history is like the stock market, ups and downs, with dark ages, but generally a little more up than down overall. We have a window of maybe a few hundred years before we inevitably fall on our knees again. Will we achieve interstellar travel before our next crash? My feeling is we may be able to send probes out to the stars, but probably never be able to send people to another Earth, and maybe not even able to receive the transmission from such probes, when they reach other Earths, because we are too busy surviving a post-apocalyptic world.

[Airbrush]

The way to make interstellar travel possible is by getting our act together and controlling population growth. Anything that can rob us of technology, and tie our hands, nuclear war or even conventional wars between nations, becomes more likely and more devastating the larger the populations are. Population magnifies everything: global warming and therefore reasons for nuclear war, even wars over water. The path to the stars is for us to not do anything to add to our natural perils (asteroids and supervolcanos) and harm our environment.

[beecee]

Travelling to the stars! A dream!! But while certainly a dream, given the time, and providing we are able to avoid any cosmological catastrophies and our own follies here on Earth, many things that we may now deem impossible, may be possible in the distant future, providing it does not contravene known physical laws and general relativity.

[Bird11dog]

I don't agree with this statement.

 

There is frequent discussion within appropriate segments of the scientific community. Interstellar travel has little scientific relevance to most scientists. Interstellar destinations would be mightily relevant, but the means of getting their is quite unimportant. There are several thousand hits in Google Scholar for Interstellar Travel - I don't see how that equates to scarcely spoken of.

 

I strongly disagree with this statement. The decision to leave the planet is a political and social decision, not a scientific one. Scientific knowledge and engineering expertise may inform the decision, but it is not a scientific decision and therefore scientists have no more part to play in discussing it than any other human.

 

This is questionable. We currently employ a hughely wasteful approach to supporting a material and energy intensive culture. Use of renewable energy and effective recycling can be great solutions in this regard. After that we have a whole solar system at our disposal. The reasons for interstellar travel are twofold:

1. Don't put all your eggs in one basket

2. I wonder what is on the other side of the hill.

 

These are different from - and, I think more important than - your proposed motivation.

 

Yes, but rather difficult. Generation ships, using hollowed out asteroids seem the easiest route. Or a combination of von Neumann devices, AIs and frozen embryos.

 

We are doing that already. Within twenty years we will have positively identified likely candidates. Within a millenium the first interstellar colonies will be established.

 

 

 

Within a millenium there won't be any humans to make the trip.

[Airbrush]

 

Within a millenium there won't be any humans to make the trip.

 

There may be humans, but they may very likely be humans that survived a dark ages after any one of a number of great perils to humanity. They would have to develop technology all over again. If there was a great dying, most people knowledgeable in industry would be gone. Nobody could figure out how to make factories work, or generate power, and certainly not design and fabricate space craft.

 

So how long would it take for humanity to emerge from a dark ages, from living in pre-industrial conditions, to restore technology? Maybe another thousand years? But by that time there could be another disaster, sending us back to pre-industrial conditions, AGAIN.

Edited June 10, 2017 by Airbrush

[Phi for All]

Within a millenium there won't be any humans to make the trip.

There may be humans, but they may very likely be humans that survived a dark ages after any one of a number of great perils to humanity. They would have to develop technology all over again. If there was a great dying, most people knowledgeable in industry would be gone. Nobody could figure out how to make factories work, or generate power, and certainly not design and fabricate space craft.

 

So how long would it take for humanity to emerge from a dark ages, from living in pre-industrial conditions, to restore technology? Maybe another thousand years? But by that time there could be another disaster, sending us back to pre-industrial conditions, AGAIN.

 

!

Moderator Note

This is a mainstream science section. No more unsupported, off-topic guesswork, please.

 

The topic is in the title.