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In search of ET: Fear of what’s out there causes split among space scientists

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Re: In search of ET: Fear of what’s out there causes split among space scientists

#31

Post by maxander »

We're already sending out a signal into the cosmos (and one more powerful than the radar signals others have mentioned)- the recent sharp upswing in CO2 over the last hundred or so years [0] would look markedly artificial, which combined with the presence of oxygen (which wouldn't stay in the atmosphere if it weren't continually renewed) strongly indicates at least a complex ecosystem, if not directly implicating an industrial civilization. Detecting light reflected from exoplanets is something we can already do, or nearly so, so we can count on this being detectable from large distances by alien civilizations with access to potentially megastructure-scale space telescopes. At that point, any reasonably curious or concerned ETs could send a probe to get a closer look.

Earth, as far as we know, is an unusual planet, and obviously so. Either we're wrong, and there's Earths all over the place, or we're alone, or ET has been keeping an eye on us for a long time already; that we're "hidden" is hard to imagine.

[0] https://www.co2.earth/co2-ice-core-data

Re: In search of ET: Fear of what’s out there causes split among space scientists

#34

Post by kerbalspacepro »

jandrese wrote: post #22

This is not something I'm worried about. Unless FTL travel is real, the amount of resources necessary to make the trip to kill off/enslave humans makes the entire effort unprofitable. Basically, if you have the ability to travel between star systems, you already have the technology to exist effectively forever in a self contained environment. You can mine asteroids/planets forever in your own solar system for effecti…

This is the wrong way to look at it. You're not thirsty for resources. You're protective of them. Imagine if you were aware of giant, angry Americans who were flying to Japan to steal all of your coke and convert all your land and resources into coke manufacturing plants.

Do you let the plane in? Do you stop it from traveling at all? Do you glass the surface of America with nuclear weapons? How do you know they won't do it to you?

Re: In search of ET: Fear of what’s out there causes split among space scientists

#35

Post by bryanrasmussen »

bovermyer wrote: post #25
bryanrasmussen wrote: post #3

Earlier quoted context omitted.

I will never understand anyone who would randomly pick a mushroom from the forest floor and start nibbling on it.

Eating mushrooms in the wild is not even remotely similar to inviting contact from other sentient species.

Was that what the parent comment said?!? I thought it was something about not understanding fear of the unknown. And then like I thought, hey is there a metaphor that might show how sometimes that it would be wise to have some little bit of wariness about the unknown at least? And then I said ah hah, there is and I wrote it down. I'm pretty sure it went something like that.

Re: In search of ET: Fear of what’s out there causes split among space scientists

#36

Post by kerbalspacepro »

maxander wrote: post #31

We're already sending out a signal into the cosmos (and one more powerful than the radar signals others have mentioned)- the recent sharp upswing in CO2 over the last hundred or so years [0] would look markedly artificial, which combined with the presence of oxygen (which wouldn't stay in the atmosphere if it weren't continually renewed) strongly indicates at least a complex ecosystem, if not directly implicating an…

If you saw a sharp change in the atmospheric composition of a planet in our solar system would you think "volcanoes" or "life"?

Re: In search of ET: Fear of what’s out there causes split among space scientists

#37

Post by Smithalicious »

Most known cases of two formerly separated civilizations coming into contact have ended like the European invasion of the Americas. I think we'd do best to be cautious unless there is at least a slim hope we could ward of an invader.

Re: In search of ET: Fear of what’s out there causes split among space scientists

#38

Post by headcanon »

rvcdbn wrote: post #15

What possible resource does Earth or human civilization possess that ETs advanced enough to pose an interstellar threat would be interested in?

Earth is a rich, temperate, naturally life-sustaining planet with a strong protective magnetic field. Regardless of what form of life an alien species would be, that may be of interest in and of itself based on mere rarity. Why bother terraforming if you don't have to?

Besides that, our solar system is otherwise quite rich. Middle-life, medium-sized star has a lot of mileage left. Being a single-star system, the planetary orbits and climates are naturally stable. Mercury has an enormous core of iron. Venus has a tremendous amount of energy stored and is a prime terraforming target for a civilization with the right technology.

We have 4 enormous gas giants, one of which forms a whole planetary system in and of itself, and could conceivably be collapsed into its own star.

The moon Titan is a giant ocean of liquid hydrocarbons.

This doesn't even get into the rich material wealth offered by the asteroid belt, Ceres, and Saturn's rings.

I'm sure there are better systems than ours from this perspective, but we're far from the bottom of the barrel. I'd sure as hell move here.

Another point is this, perhaps the potential of humans themselves presents a threat to another spacefaring civilization. What if they've seen species like ours rise up and conquer, and they'd prefer to nip it in the bud instead of waiting around for us to become more powerful?

Re: In search of ET: Fear of what’s out there causes split among space scientists

#39

Post by jandrese »

jkartchner wrote: post #17

I figure it's all moot anyway. We are probably alone in the universe. Fermi's paradox is a thing.

I don't think we're alone. But I do think we're kind of trapped in our Solar System along with everybody else. Interstellar travel is so outrageously expensive that by the time you have the technology to do it you necessarily have the technology that makes it unnecessary.

An interstellar journey means you need a ship that can survive indefinitely in deep space, where you don't get free energy from solar panels or have easy access to comets to mine for materials. An in-system habitat has to be a solved problem before you can even consider building one. But at that point you have effectively unlimited living space, energy, and materials so why bother?

Even if your sun is turning into a red giant you can move your habitats to the optimal distance to sustain life. It's really hard to imagine a time when Humans have used up the entire mass of the other planets in the solar system and need to look outward for resources. You could build an almost unimaginable number of O'Neill cylinders using only the mass of Jupiter.

Re: In search of ET: Fear of what’s out there causes split among space scientists

#40

Post by mrob »

sbuttgereit wrote: post #19

I think the fears of some ET empire with Darth Vader (or similar) at the head is very misplaced. Just think of the economics... "let's go exploit that world 10 LY away from us that we don't fully understand and which will still takes us an insane amount of time to enslave and milk resources from!" What a scalable strategy given the size of space... one might even say it's astronomically large! The resource consumptio…

The motivation isn't exploiting Earth resources, but killing us before we can kill them. Most humans don't believe non-human species have any right to life, so why would sapient aliens believe humans have any right to life? Humans have a non-zero probability of growing powerful enough to be an existential threat to the aliens, so the safest option is to preemptively eliminate them.

And even if the aliens are convinced that humans are 100% alien-friendly, it would still make sense to kill us all because there's a chance we'll develop uncontrolled recursively self-improving AI ("intelligence explosion"), which would be a threat to the aliens without us intending it.

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