Ever seen a UFO?

[jimbunyard]

Originally Posted by OldManMirage

Mike, I would not dare to contradict you, but...

This is where the all the aspects of the Fermi paradox have to be considered. One of them is time. Even with our current level of technology, given enough time we could reach across our own galaxy. Given the estimated age of said galaxy, and the fact that many stars are much older than ours, IF - and that's the crux - IF life is common, there has been more than enough time for other species to do the same.

Indeed, consider them.

And consider this.

The Milky Way is roughly 200,000 light years across. (a light year is about 6 trillion miles) The nearest star is about 4 light years away. Our "current level of technology" puts us there in about 40,000 years. So 200,000 divided by 4 is 50,000; 50,000 times 40,000 is 2,000,000,000 years to 'cross' our galaxy at our current technological level, or roughly a seventh the generally accepted age of the universe.

So yeah, there's enough time...


Leaving out, for humans at least, (since the 'little green men', wth their super-special alternative 'laws of physics' will have resolved these petty earth-biology problems), the effects of zero gravity on gravity-evolved life, or the same for radiation, or to venture into the science-fictiony world, the effects of increased mass on biology at even small (5-10%) of light speed [may not be a thing since, if I remember correctly, the mass increase is not linear with an increase of speed], or the bodily effects of time dilation.

Or, from a more physical standpoint, how does one slow down after acheiving 5% light speed? How long does it take, and how much 'juice' is required to even change the velocity of a billion tons moving at 67,000,000 miles an hour (10% light speed)? Di-lithium crystals? And before it's suggested, qravity is by far the weakest 'force' in the universe; by comparison the electrical force is 2.4 x 10e43 (that's 10 followed by 43 zeros) stronger. So, not only would one need an anti-gravity machine, one'd need an anti-gravity multiplier as well... And, if I'm not mistaken, both are subject to the inverse square law.

Or to return to biology. How do you gene-engineer a section of fish chromosome to enable a warm-blooded animal to freeze, since hibernation will not suffice for the time spans required?


As has been stated repeatedly before, it is the epitome of arrogance to assume that 'life' is restricted to our lonely planet, but it is by defiinition not 'common' because, again by definition, the exponentially most common 'constituent' of the universe is 'space', or perhaps more acciurately, vacuum, hence life must be very rare indeed. And 'intelligent' life would be an order of magnitude more so.

Leaving out the nebulous 'existances' of dark energy and matter...

Saw a blurb the other day proclaiming the 'confirmation' of 'life' on some moon or other, didn't even click on it because of my certainty of what that 'confirmation' will be; the detection of some atmospheric constituent 'unproducable' except as a byproduct of life. I want real, physical proof, and the quickest, one way Jupiter-orbit 'flight' is about 5 1/2 years, so 11 years for a sample to return home, were that even possible (it's not, at least at this time). Just an example of the most basic of problems confronting the god-like 'little green men'...

[Mike OReilly]

Originally Posted by OldManMirage

Mike, I would not dare to contradict you, but...

This is where the all the aspects of the Fermi paradox have to be considered. One of them is time. Even with our current level of technology, given enough time we could reach across our own galaxy. Given the estimated age of said galaxy, and the fact that many stars are much older than ours, IF - and that's the crux - IF life is common, there has been more than enough time for other species to do the same.

I agree... it's what I was trying to say. There's nothing impossible about interstellar travel. Heck, we now have two spacecraft doing just that (Voyager I & II). It's just that it takes a very long time to get anywhere interesting. And if we're talking about transporting anything we'd recognize as life, it would require considerable technological and resource effort.

Given all this, it seems incongruent that an alien race would go through this tremendous effort, arrive at a planet with at least quasi-intelligent life, and then only reveal itself fleetingly or to fringe individuals.


But here's another wrinkle. While it remains statistically inconceivable that we are the only space-faring intelligence in our galaxy, it may not be inconceivable that we are one of the early such species to emerge. This is where I think Fermi may have missed an important consideration:

Anything we understand as life requires an abundance of heavier elements such as carbon, oxygen, sodium, magnesium, calcium, and a whole host of other atoms. NONE of these are present in the early stages of the Universe or our galaxy. Early generation galaxies and stars are almost 100% made up of hydrogen and helium.

You've often heard the phrase: "We are star-stuff." And we literally are. All heavier elements beyond helium are manufactured in stellar cores. So our entire solar system is, at very least, a second generation creation. There had to have been at least one full life-cycle of stellar birth, life and death in this region for Sol, and all our planets, to be created.

Given that it has taken ~4.5 billion years for Earth (and us) to get to this stage, and given there had to have been at least one stellar cycle before our sun, and remembering our galaxy is estimate to be between 10 and 13 billion years old, it's not inconceivable that we are one of the earliest civilizations that could emerge.

[OldManMirage]

Originally Posted by jimbunyard

Indeed, consider them.

And consider this.

The Milky Way is roughly 200,000 light years across. (a light year is about 6 trillion miles) The nearest star is about 4 light years away. Our "current level of technology" puts us there in about 40,000 years. So 200,000 divided by 4 is 50,000; 50,000 times 40,000 is 2,000,000,000 years to 'cross' our galaxy at our current technological level, or roughly a seventh the generally accepted age of the universe.

So yeah, there's enough time...

.

Here's how I see it when I say "Our current level of technology."

If we devoted the resources to it, I think we could easily build generational ships capable of reaching speeds in excess of a million miles an hour. We can do about 50,000mph now, so I've always considered it a reasonably attainable speed.

Someone check my math on this and post if I'm wrong, but I believe that would get us to good 'ol Alpha Centauri in about 3000 years, give or take a century or two.

Start sending out ships to all local stars, and in about 10,000 years you've hit quite a few. In a 100,000 years, you're the dominant species in your local neighborhood. In a million...well...who knows ?

My point is always there has been more than enough "Million Year Epochs" of time in our galaxy that IF there were other species out there - they would have showed up by now.

Hey, I guess its possible that "they" could be "us." There was a great Twilight zone episode of just that very premise.

[SeanPatrick]

Originally Posted by boatman61

Makes me smile when the 'Brains' always assume 'Little Green Men'..
Kinda limited when one considers the skills and co-operation many insects have developed to deal with their environments and successful survival..

I've often wondered if we would even recognize aliens for what they are if they arrived. There was an episode of [the original] Star Trek where some of the crew were sped up to the point that the rest couldn't even see them anymore. But they did hear them talking in the form of a high-pitched buzzing. On the other hand, the crew who were sped up saw everyone else as motionless - almost like statues.


Then there are the various H.P. Lovecraft stories about alien races that can "swap" consciousness with any other race in order to study them. In the event their own race dies or their homeland is destroyed, they can simply mass-migrate their minds to another civilization on the other side of the universe.


Who knows? Maybe they're here right now.

[jimbunyard]

About all that's left to say is that a lot of people seem to have a lot of problems determining the difference between science fiction and science fact...

A million miles an hour will put you 4 light years away in 2740 years. So what?

Ever heard about minimum population requirements for civilizational survival, let alone progress? What about species interdependence for biome perpetuation?

Again, it is extremely likely that humans will be forever moored to this planet, and certainly to this solar system, and the absence of evidence for 'little green men' can be taken as 'proof' that this is generally the case for the rest of the universe.


But 'ET' could show up tomorrow...

[GordMay]

Will it be safe for humans to fly to Mars?

A Mars Mission would be viable, if it doesn’t exceed four years, an international research team concludes.

This doesn't bode well, for interstellar travel.

Sending human travelers to Mars would require scientists and engineers to overcome a range of technological and safety obstacles. One of them is the grave risk posed by particle radiation from the sun, distant stars and galaxies.

Answering two key questions, would go a long way toward overcoming that hurdle:
Would particle radiation pose too grave a threat to human life throughout a round trip to the red planet?
And, could the very timing of a mission to Mars help shield astronauts and the spacecraft from the radiation?

In a article [1], published in the peer-reviewed journal Space Weather, an international team of space scientists, including researchers from UCLA, answers those two questions with a "no" and a "yes."

That is, humans should be able to safely travel to and from Mars, provided that the spacecraft has sufficient shielding, and the round trip is shorter than approximately four years.

And the timing of a human mission to Mars would indeed make a difference: The scientists determined that the best time for a flight to leave Earth would be when solar activity is at its peak, known as the solar maximum.

[1] “Beating 1 Sievert: Optimal Radiation Shielding of Astronauts on a Mission to Mars” ~ by M. I. Dobynde et al
➥ https://agupubs.onlinelibrary.wiley....9/2021SW002749

[OldManMirage]

Originally Posted by jimbunyard

About all that's left to say is that a lot of people seem to have a lot of problems determining the difference between science fiction and science fact...

A million miles an hour will put you 4 light years away in 2740 years. So what?

Ever heard about minimum population requirements for civilizational survival, let alone progress? What about species interdependence for biome perpetuation?

This is why I said IF we devoted the resources to it. And it is a hypothetical situation I used trying to demonstrate the Fermi paradox.

But I do believe that using even present technology it is possible. It would take cooperation on a global scale that is impossible to imagine at the moment. But the resources are there.

Generational ships the size of cruise ships could be built in orbit and populated with sufficient numbers of people and bio-matter. They could be launched toward likely destinations. Some would probably get lucky and hit habitable planets - IF there are such.

And again, this is crux of the Fermi paradox. IF - big IF - but if this and if that and if life is common, and if little old us could do it, then the odds are that other older and more advanced - and more cooperative - species' would have already done it.

I imagine a species with a more "hive-type" mentality would rule the galaxy.

"All hail the Queen Ant !"

And yeah...they certainly could show up anytime !

[jimbunyard]

You're not even talking science fiction, you're talking science fantasy. A cruise ship-sized intragalactic colony vessel would probably be at least an order of magnitude too small, we have no known method of propelling, or, more importantly, braking it, and no way to get the materials to build it into space.

Even a cruise ship sized 'space ship' would take 2000 NEO launches, (not including construction equipment, fuel, consumable and population launches) if we were able to launch 100 ton payloads, which 'we' (any individual Earth organization) currently are not.

The 'resources' required would bankrupt an already bankrupt planet, economically, physically and energetically.


'Beliefs' do not connote reality; and quite often do the opposite.


Ever read the 'Ringworld' trilogy? The 'Puppeteers' had the right idea; they 'figured out a way' to move their entire planet (actually [in the books], five of them, along with an artifical sun).

Of course, imagination is not bound by the laws of physics...

[AKA-None]

Originally Posted by OldManMirage

This is why I said IF we devoted the resources to it. And it is a hypothetical situation I used trying to demonstrate the Fermi paradox.



But I do believe that using even present technology it is possible. It would take cooperation on a global scale that is impossible to imagine at the moment. But the resources are there.



Generational ships the size of cruise ships could be built in orbit and populated with sufficient numbers of people and bio-matter. They could be launched toward likely destinations. Some would probably get lucky and hit habitable planets - IF there are such.



And again, this is crux of the Fermi paradox. IF - big IF - but if this and if that and if life is common, and if little old us could do it, then the odds are that other older and more advanced - and more cooperative - species' would have already done it.



I imagine a species with a more "hive-type" mentality would rule the galaxy.



"All hail the Queen Ant !"



And yeah...they certainly could show up anytime !

Enders Game?

[AKA-None]

Originally Posted by jimbunyard

You're not even talking science fiction, you're talking science fantasy. A cruise ship-sized intragalactic colony vessel would probably be at least an order of magnitude too small, we have no known method of propelling, or, more importantly, braking it, and no way to get the materials to build it into space.

Even a cruise ship sized 'space ship' would take 2000 NEO launches, (not including construction equipment, fuel, consumable and population launches) if we were able to launch 100 ton payloads, which 'we' (any individual Earth organization) currently are not.

The 'resources' required would bankrupt an already bankrupt planet, economically, physically and energetically.


'Beliefs' do not connote reality; and quite often do the opposite.


Ever read the 'Ringworld' trilogy? The 'Puppeteers' had the right idea; they 'figured out a way' to move their entire planet (actually [in the books], five of them, along with an artifical sun).

Of course, imagination is not bound by the laws of physics...

Oumuamua?

Rendezvous with Rama?

[kmacdonald]

Proof of vaccination will be required of all visitors.

[Mike OReilly]

Interstellar travel for humanity right now is barely technologically conceivable (not achievable, but conceivable). But then there's even the question of, where would we go? We have no hint of any life out there yet. Heck, we haven't even found life outside of Earth in our solar system. So where would we go?

Besides, as I mentioned earlier, Fermi's Paradox might not be paradoxical at all. Given the only data point we currently have (us, on Earth), it is conceivable that we are at the early stages where intelligence can evolve and explore space. Given the necessity of having heavy elements, and given our own evolutionary history, it's possible we are one of the first intelligences to emerge in this galaxy.

So maybe we are one of the First Ones.

[cyan]

Originally Posted by jimbunyard

Or, from a more physical standpoint, how does one slow down after acheiving 5% light speed? How long does it take, and how much 'juice' is required to even change the velocity of a billion tons moving at 67,000,000 miles an hour (10% light speed)? Di-lithium crystals? And before it's suggested, qravity is by far the weakest 'force' in the universe; by comparison the electrical force is 2.4 x 10e43 (that's 10 followed by 43 zeros) stronger. So, not only would one need an anti-gravity machine, one'd need an anti-gravity multiplier as well... And, if I'm not mistaken, both are subject to the inverse square law.

Why must we be limited to applying Newton's equations, decades after quantum mechanics poked holes all over them?

If a craft could be gently accelerated at 1G for an Earth year, it could reach-err-approach the speed of light. We just like to assume that some sort of "juice", squirted out the back side is the only way to accelerate, because that is how it's been done so far.

I see it as quite likely that a trip to Proxima Centauri, 4.3 light-years away, will be possible with a duration of less than a decade relative to the travelers. (no need to come back, unless a trip into Earth's future is desired)

A reactionless drive or some other future technology seems as just inevitable to me as the accurate rocket guidance technology that once produced my paychecks. Some of my colleagues (mistakenly) thought that we had created the best such devices that the world would see... for a century at least. A couple years later, some clever guy figured out how to measure the interference of two lasers in a ring, and that proud claim was dust.

My fascination here is with our static assumptions of human technology and our confidence in our current understanding of physics. In my experience, the only correct assumption is change. To both.

[jimbunyard]

Reactionless thrusters? Venturing into semantics-land here, your 'open' scientific human mind can't even articulate the concept you seem desperately to want to believe. I.e. 'reactionless thruster' is an oxymoron; the purpose of 'thrust' is to provide a reaction, in this case 'movement' from point A to point B.

We continue to use Newton's equations because they still apply to uses we put them, as they always will. Quantum mechanics hasn't 'superceded' Newton's laws (nor has it "poked holes all over them"); it deals with a different realm, the nature of the subatomic world.

As far as I know there are no, zero, nada existing or even proposed technologies that obviate the need for a real force to change the motion of a massive body, 'gentle' or 'violent', spread out over speed-or-gravity-dialated time or executed in the 'briefness' of the deepest gravity-poor regions of the universe.

Once again, if 'our' laws of physics are so transient, where are the 'beings' who transcend them? Or are you prepared to claim that we're the only beings who've ever advanced to our exalted state of 'match riding' to NEO and very occasionally our closest planetary neighbors?

My fascination here is with the near-constant conflation of the realities of the physical world with the abilities of human technology and the imaginations of those with myopic views of the future.

There are no free lunches, regardless of one's universal location. Except in the imagination. There are limits, which is why stars burn out or explode, and oceans boil away, and hurricanes form, and life evolved and continues to evolve, and so on, perhaps ad infinitum, down to the persistance of quarks.


More science fantasy. Come back when you have some science reality.

[cyan]

Originally Posted by jimbunyard

Reactionless thrusters? Venturing into semantics-land here, your 'open' scientific human mind can't even articulate the concept you seem desperately to want to believe. I.e. 'reactionless thruster' is an oxymoron; the purpose of 'thrust' is to provide a reaction, in this case 'movement' from point A to point B.

We continue to use Newton's equations because they still apply to uses we put them, as they always will. Quantum mechanics hasn't 'superceded' Newton's laws (nor has it "poked holes all over them"); it deals with a different realm, the nature of the subatomic world.

As far as I know there are no, zero, nada existing or even proposed technologies that obviate the need for a real force to change the motion of a massive body, 'gentle' or 'violent', spread out over speed-or-gravity-dialated time or executed in the 'briefness' of the deepest gravity-poor regions of the universe.

Once again, if 'our' laws of physics are so transient, where are the 'beings' who transcend them? Or are you prepared to claim that we're the only beings who've ever advanced to our exalted state of 'match riding' to NEO and very occasionally our closest planetary neighbors?

My fascination here is with the near-constant conflation of the realities of the physical world with the abilities of human technology and the imaginations of those with myopic views of the future.

There are no free lunches, regardless of one's universal location. Except in the imagination. There are limits, which is why stars burn out or explode, and oceans boil away, and hurricanes form, and life evolved and continues to evolve, and so on, perhaps ad infinitum, down to the persistance of quarks.


More science fantasy. Come back when you have some science reality.

I do not believe "semantics" was the word for which you were searching. I did not speak of thrust.

I do admire your conviction, though, along with that of Lord Rayleigh and Sir James Jeans. While the classical (Newtonian) equations of the latter two were famously dispensed in what became the Ultraviolet Catastrophe, the quantum physics that ensued might be worth a look in your case. If your mind becomes open enough to move beyond Newton you may be able to accept the spooky quantum entanglement of two particles that can now be demonstrated over many miles. (yes, plagiarizing Einstein here) Only when that blows your mind, have you sufficiently understood it. Talk about violating classical physics! Give it a try.

You could follow that up with a study of the Quantum Eraser, seemingly with the ability to change the past with experiments that can be performed today.

I suspect that you would enjoy such things.

Peace.