I am sure of a few things.

We are not alone in the universe.

I am sure that civilizations have risen and fallen everywhere. There are some places where unicellular life is just beginning, some places where life has just begun to emerge onto land, somewhere there are people who are the equivalent of us currently and doing the exact same thing, and somewhere is 100K years ahead technologically.

There is also life that we can't explain. Silicon based, gas based, life on a subatomic level.

There is life that we can't see. They exist in infrared or ultraviolet. They exist in gamma. Perhaps in radio waves.

There are beings of light, beings of time, beings who live on a scale that we can't even comprehend.

There is also a multiverse where infinite yous are doing slightly different things at slightly different times, where the differences create an entirely new timeline for that particular you.

There is also somewhere where other you and other me are having this exact same interaction.

I think we are all too far apart in spacetime to interact. We may find unicellular and bacterial life in our system, maybe even fish-type life on Io or Ganymede. I hope so.

Loved Tintin, did not know he had the same idea 😀

It takes a lot of fuel to do anything in space. This would be a very inefficient use of something that is very essential elsewhere, and very heavy.

Also, nuclear engines are very efficient, yes. But they do not produce a lot of thrust, so it would be very difficult to sustain an acceleration that high.

In the Tintin comic, “Destination Moon,” they do exactly this. The rocket is nuclear powered, maintains 1g acceleration until the halfway point where they flip and decelerate. Takes them only a few hours.

Could you send them forward? That sounds interesting but I'm assuming this is humans meeting aliens so Avatar is probably one example.

We don't.

I've read tons of stories dealing with alien encounters where the aliens are less advanced.

Please google the term "Aldrin Cycler" if you prefer it in sci-fi, The Last Dance by Martin Shoemaker.

Edit: I'm suggesting this because of current economics. We are a way off from the 1G continuous acceleration being feasible.

Yes, it would work, and you'd only need to flip once at the midpoint of the trip. But we don't have the technology now to maintain that kind of acceleration.

Or perhaps almost no other intelligent alien species go through this process of "civilisation". Consider other intelligent human species and how they didn't have an agricultural revolution or civilisation. If Homo Sapiens hadn't arisen, would we be a planet with no intelligent species?

Sure, but we're assuming there are any aliens who can travel to Earth.

Yep, you could get to Mars in less than a week at 1 g, flipping halfway to decelerate:

https://space.stackexchange.com/questions/840/how-fast-will-1g-get-you-there

You're just going to need a lot of fuel.

And I agree that there must be intelligent alien species like us out there, but what I'm saying is perhaps they're just so rare, even rarer than Drake's Equation suggests because he didn't include what a species wants to do.

Did Neanderthals or Homo Erectus want to become a technologically advanced, "civilised" species? Did most hunter-gatherer humans choose this form of society or were they replaced or subsumed by human groups that did want to do this? Look at pre-historic Europe, Neolithic farmers were known for creating segregated societies and replacing entire areas with members of their own and leading to the near-extinction of Western European Hunter-Gatherers. And that's just one case. The Yamnaya people also replaced large parts of Europe. And that's just one small continent. This happened everywhere around the planet, but mainly with our species. If there weren't any groups of "civilised" humans or if those groups were defeated by hunter-gatherer humans, perhaps we'd be just like our ancestors were for 95% of our history.

Perhaps, intelligent aliens species just didn't go down the same path because they didn't want to.

I will add to this that the lifespan of a civilization after its industrial revolution might be quite short.

Our own industrial revolution has given rise to two existential crises so far -- the threat of global thermonuclear war, and the threat of climate change. The first seems to be behind us, mostly, maybe, but there were some really close calls during the Cold War. We came this || close to going out forever. The second has yet to fully play out.

Those are just the existential crises which have emerged in the 260 years of industrialization, which in the cosmological timeframe is less than the blink of an eye. If we survive this one, there will doubtless be more.

For all we know, all civilizations in the galaxy follow the pattern of a long pre-industrial existence (3.4 million years, in our case), followed by a very short industrial period, ending in annihilation.

If that's typical, then technologically advanced civilizations would only account for about 0.008% of all alien civilizations.

And in reality, they very likely wouldn't. But until we make contact with an alien culture and learn to understand it, we're limited by what we do understand.

Any aliens able to travel to earth will be more technologically advanced than us.

They didn't do it in horseback

That makes sense, but it doesn't seem like a good idea to assume alien species behave the same way we do.

I think the discussions usually revolves around aliens being here. Were just now barely going back to our own moon. So if there here..... They're crazy advanced. As far as aliens on other planets , in other stat systems. Can't really make an assumption. Could be anything there

>What I'm saying is, perhaps we're the only intelligent species to have gone down this specific route of industrialisation to sending radio waves into space.

there are a lot more "perhapses"

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> what if aliens simply aren't taking the same path we are (even though they may be as intelligent or more intelligent than us) and so that's why we haven't found any evidence; they're just not doing the same things as we are. If this is the case, then perhaps the nearest species that went a similar path to us is so far away and so uncommon that we may never know about them.

that is also possibly correct.

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there must be tons of civilizations.

https://en.wikipedia.org/wiki/Drake_equation

The Drake equation is a probabilistic argument used to estimate the number of active, communicative extraterrestrial civilizations in the Milky Way Galaxy.

...then where are they?

https://en.wikipedia.org/wiki/Fermi_paradox

The Fermi paradox is the discrepancy between the lack of conclusive evidence of advanced extraterrestrial life compared to the apparently high a priori likelihood of its existence.[1][2] As a 2015 article put it, "If life is so easy, someone from somewhere must have come calling by now."[3]

>Why do we assume

because it's all we KNOW.

we use radio, if ET uses radio, maybe we get lucky.

but since we have no idea what other means to employ - what can we possibly use other than that which we know?

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they could just as easily not have eyes, ears or mouths.

I was thinking about permanently 1G for the duration of the journey.

Have 5G on my phone, does not work well on Mars :)

It’s possible since all our tech advances have come because of outside stresses

We can't describe civilizations we can't imagine, so we create stories similar to what we know.

I feel that's completely fair for us to think that way, but it doesn't seem like a good idea to think of intelligent aliens that way when not even other intelligent human species took the same path we did.

I didn't have to read a god damn bit of this to answer you.

My person, can WE travel across the galaxy to other planets in our lifetime?

Do we have that tech?

No, no, we don't.

Ive got 4G on my phone so I’m sure they can think of something eh

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