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K2-18 is a flare star.

  > the agency also hinted at even more remarkable possibility in the
  > potential finding of a molecule called dimethyl sulfide (DMS), which
  > on Earth is only produced by life.
Are there any other instruments or telescopes that could further investigate this? Or is JWST the only telescope instrumented to detect such molecules 120 LY far away?
I can't see a molecule on my desk, even with a jeweller's microscope, nevermind seeing one 120 million light years away!

Science is amazing.

It is amazing, but JWST is not really seeing individual molecules. I believe they are analysing the spectral atmospheric emissions.
You're actually seeing tons of molecules on your desk. You just can't resolve them individually. Neither can the JWST.
So if we're not seeing individual molecules, why talk about molecules? Its fine to talk about desks or whatever we can actually see, right?
The JWST is essentially “seeing” them the same you see all the molecules in front of you in your desk: from the light they scatter or absorb.
Does anybody know if this is the first time ever they detected DMS?
It's not really "seeing" them but the absopbtion of light in certain wavelengths that shows what's present in the exoplanet's atmosphere. There's a whole new branch of sience looking for bio and techno signatures from exoplanets. Exciting times!
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If the presence of dimethyl sulphide is confirmed, what would the next steps be? Presumably sending a probe would not be feasible in any foreseeable timeframe?
The best time to send a probe to an exoplanet is 200 years ago. The second-best time to do it is now.
Perhaps not, if the speed you can drive a probe is increasing with technological development it might be a waste of time to send a probe that'll be overtaken by its newer sisters.
The technological development is driven by the need to launch the probe. You need to start somewhere.
And what's more is we'll probably send the next probe someplace else.
No, sending it several million years ago would be better.
> Presumably sending a probe would not be feasible in any foreseeable timeframe?

With global resources we can do it easily but the people in charge of our countries wouldn't have a job if they didn't invent fake boogeymen to waste cash on instead.

We have plenty of starshot proposals that are incredibly cheap compared to other things: https://en.wikipedia.org/wiki/Breakthrough_Starshot

.....

How do you propose getting a probe to something 120 light years away and getting an answer within a human lifetime, unless you're going for a ride on the probe? Do you have some new physics?

The Centauri system is 4 light years away, my link shows a proposal of how to do that with a flyby, it's most certainly not the only starshot proposal just the one with a prominent billionaire like Mark Zuckerberg behind it so I thought perhaps the best to put out there for people to see as an intro to the concept.

These are very real ideas with very real engineering designs by incredibly smart people. It's not sci-fi mate, we can actually do this with enough wherewithal.

Right.... but 4 light years is one thirtieth as much as 120. Unless you find a way around relativity I don't see how anyone alive now would get results from a mission to something 120 light years away, regardless of its velocity. Unless we vastly increase human life span, which might be the easier option.
Next steps will be: Observation, more observation and if it remains sufficiently interesting then perhaps some bespoke observation. Nothing will be sent in the foreseeable future.
This star is 124 LY away. If we launched our fastest ever probe in that direction, which was New Horizons, it would take 2.2 million years for it to reach the system. Assuming the probe could then be still operational to transmit back data, it would then take 124 years for the data to be received.

So the next step would be to build better and better telescopes to observe these planets, learn about their composition, and inspire people to study and fund the sciences.

There are some proposals of how to build fast probes that could visit very close star systems that could maybe, maybe reach a the 4 LY to Proxima Centuri within a human lifetime. But 124 LY is so far that even the Starshot proposal would take nearly 800 years to receive data back.

https://en.m.wikipedia.org/wiki/Breakthrough_Starshot

Well... nothing? These kinds of news pop up from time to time, but that's the end of it. It's ridiculously far away, and there is little we can do, at least within any foreseeable time frame.
We won't be visiting any time soon. But news of (likely) life would increase funding for telescopes, and eventually we'd get some idea how common life is - which is an interesting little fact in itself.
The problem is, when would we get an answer? Even in the best case, that would be 240 years. But we don't have the capability of building probes which approach the speed of light, so with current technology, it is probably hundreds of thousands of years.

So the short term solution (in the order of decades) is improve the observation capabilities. More observations with the JWST should give a better idea what the next iteration of a space telescope for this job should be and give some motivation of accelerating building such a telescope. JWST itself took decades to build and deploy. It would be remarkable, if an improved telescope could be deployed in a 10 year time frame. Of course, an operational Starship would help a lot with that, as a lot of effort for JWST was the complex deployment mechanism.

We won't get the capability to build probes that approach the speed of light if we keep observing instead of beginning to build the probe.
Nobody said something about stopping building probes. That will continue and eventually lead to probes which might approach the speed of light. But the achievable targets for the next decades are planetary, not interstellar.
Nobody said anything about stopping building planetary probes.
If you want to send things there, I would say the best solution is to take this as evidence that interesting exoplanets exist, and to look for similar closer ones
Distance is 120 light years. So whatever we see is 120 years in the past. Getting there within a reasonable time frame is impossible with our current technology (an unmanned rocket will still needs 1000s of years). The good news: if there is intelligent life it will not easily get here either.
> The good news: if there is intelligent life it will not easily get here either.

Unless 'it' left a long time ago and is already here.

I always feel the 'space is big haha no one can cross it' argument is weird due to always framing it in our own frame of reference. What if the hypothetical 'thing' is like a jellyfish and time isn't as big an issue, or an AI that definitely doesn't care about time. Or a bundle of fungus that doesn't necessarily care one way or another.

If you have enough acceleration , you can travel 1000 light years in a human lifetime.

It’s just that when you return, at least 2000 years will have passed on earth.

so you're implying speed atleast 10x the speed of light? i think you'll have better luck increasing the human lifespan instead.
Not that's not what he is implying. He is talking about time dilation.
How does one travel 1000 light years in a span of human lifetime (~80 yrs) if you’re not going faster than the speed of light?
Time dilation! Time is relative. For an outside observer, over 1000 years pass, but aboard the ship, much less time passes. There are calculators for this, e.g. at [0]. If you constantly accelerate at 1g, flip around at the halfway point and accelerate in the opposite direction for the rest of the journey, roughly 13 years would pass from the traveler's perspective.

This site also has a "Newton's universe" mode, which pretends that relativity doesn't exist. Interestingly, in that case you would take over 44 years!

[0]: https://www.omnicalculator.com/physics/space-travel?c=EUR&v=...

I am pretty rusty in special relativity, but IIRC, in the ship it basically seems like the distance is contracting as you accelerate. And from earth, it seems like time is going slower inside the moving spaceship.
With relativistic time dilation. 1000 years will pass on Earth, but on tge ship, it will be only a couple of decades, assuming they're close enough to the speed of light.
""" Time dilation is the difference in elapsed time as measured by two clocks, either due to a relative velocity between them (special relativity) or due to a difference in gravitational potential between their locations (general relativity). When unspecified, "time dilation" usually refers to the effect due to velocity. """

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

wow thanks! this was super fun, do you happen to have some souce about the calculations that go into determining the time dilation based on different velocity? i'm aware about black holes being capable of well, doing time dilation thingy due to their massive gravitational force but nothing else.

edit: souce as in something a regular average joe can make sense of haha

Well, depending on your preferred format there's a great book called A Brief History of Time - https://en.wikipedia.org/wiki/A_Brief_History_of_Time , or lots of videos about it at https://www.youtube.com/results?search_query=time+dilation

More broadly, the series Cosmos with Carl Sagan was excellent, and is worth a view. The bit about time dilation is at https://www.youtube.com/watch?v=kWgEzxi_A0w . The more recent one with Neil Degrasse Tyson is also good (but while I enjoy both, I think I prefer the older one)

1g constant acceleration is enough. But we don't have the technology yet.
Even simpler: you send out self-replicating AI drones in advance—to every star in the entire galaxy. That guarantees permanent security. The drones assess if alien intelligences have any potential to become a threat, and if so annihilates their planet, by autonomous decision.

Takes a few million years to set up... but that's just a blink of an eye on cosmic time scales; a brief era in the galactic-scale lifespan of an advanced civilization. (The civilizations that don't do something like this don't live that long).

But those evolve later and come back to you, biting you in the ass.
That's something we are very good at
This is one of these things that sound easy as long as you don't think about the details :)

Annihilating planets takes a lot of energy. For example if our Sun goes supernova it will maybe kill all life on Earth, but the planet will still exist.

If you gather enough energy to potentially annihilate a planet in each star system in a galaxy - you won't need to worry about any civillization becoming a threat in the first place, because they won't have any energy left to become that threat :)

Then there're the problems with relying on autonomus system with such energy at its disposal, and the problems with dealing with genetic/cultural drift. What if your species diverges into several ones that start fighting each other - which one is the one that's supposed to be protected from the other? What if different parts of this system disagree?

Who gets to push updates to the code of this system? How do you supervise this? Imagine a military coup or constutitional crisis and you're the guy that keeps the ssh key :)

Are distant colonies that get independence and develop on their own a threat? Would the regions that want autonomy agree to this? Or if this technology exist - wouldn't it be used for wars inside that species long before they can start to worry about the so-far-uninhabited rest of the Galaxy?

Would they even survive long enough to create this?

Imagine Sumerians created such system on Earth and it wakes up after 5000 years and asks us for password in some dead language or else :) Now change that to 1 000 000 years.

In my opinion it's very unlikely something like this ever gets created simply because of all the coordination and trust issues, the energy and technology dependencies, the probability and severity of problems it can cause vs the problems it can solve.

Wasting significant percentage of energy of the galaxy and risking destroying it accidentally just to save yourself some diplomacy sounds like the ultimate tech solution to people problem :) And you're not really avoiding the diplomacy, you're just doing it upfront - internally. I'd be very surprised if there were no wars caused by someone trying to implement such idea.

Imagine writing a proposal to Congress or EU to start doing this :) And how Chinese and Russian would react.

Our sun isn't massive enough to supernova, thankfully.
Huh, sounds like those Von Neumann probes from Star Control II
We are the self-replicating drones.

It's taking a few million years to get from violent confused simians to violent confused simians with autonomous AI. But we're getting there.

The thing I always found a bit unnerving is that if they've left and are traveling at a speed close to the speed of light we'd never know until they arrive. If something is traveling at the speed of light towards us (whether a ship or a death star laser) we wouldn't know until it arrived.

Now we've been sending radio signals for several decades you have to begin to question if there's a civilisation out there maybe 10-100 light years away that may now be aware of us and have sent something our way which may be about to arrive.

There is an explanation for Fermi paradox that suggests maybe alien civilisations choose to be quiet or immediately wipe out other transmitting civilisations with speed of light weaponry.

Why? Well, if there's no way to have prior warning of an attack traveling at the speed of light your only defence is some combination of remaining hidden and extreme hostility towards other civilisations.

Most likely explanation? You can't travel at close (even 1%) of the speed of light without dealing with interstellar gas compression, object collision, passing through any moderately strong magnetic field without deviating, etc
Slow, long-duration mission have their own issues. Even a jellyfish or fungus has to eat. Carrying enough food for a multi-thousand year mission is a problem. And an AI needs power, which might be hard to come by between the stars.
> Unless 'it' left a long time ago and is already here.

Might be posting on HN right now. Never know.

All your hypotheticals are not entirely unreasonable, but they are also so far beyond our current ability to test, that it becomes pretty futile to speculate, except as a source of entertainment.

Space is reaaaaaaaaaaaaaally big, much bigger than people really have a conception of. Bigger than I have a conception of, and I try really hard to understand how bad my conception of it is.

A space fungus from 120 light years away would presumably only reach us by almost 100% chance, which is something I am comfortable saying is almost 100% unlikely. This is true of most hypothetical threats.

Fantasies about aliens or AI coming here (or sending big rocks) to exterminate are as weird to me, as I image "space is big haha" is to you.

There is no reason for anyone even to try to cross interstellar distances, especially not for war. The expected gain will never be worth the cost, outside of some fantasy FTL-for-free engine, which is just that: fantasy.

But, it is fun to think about it all.

120 light years is nothing. Light is pretty slow seen from the cosmic scale.
> if there is intelligent life it will not easily get here either.

We made need to redefine intelligent life if we think of ourselves as the pinacle of intelligence or rather in the upper eschelons.

And if you think about it... 100-200 years of progress can be pretty significant. Just look at human civilization.
Time to build a railgun in space and get some probes to K2-18 b.
We can expect these posibilities: 1. no life 2. simple life 3. advanced intelligent civilization

In the first two cases, we need to send a physical probe there. In the third case it might be enough, and much faster, to send communication signals there and get answers back. The third case is also arguably the most interesting.

Why not aim an antenna at it, and download the answers to the questions of the universe?
Because it's directional communication (point-to-point), in order to be energy-efficient over long range.
1. They may have found us and may have directed a communication beam at us.

2. The technology they use may be so advanced as to overcome any power problems.

If 3, And The are truly advanced we should consider not communicating with them. Maybe they are hiding from someone else... ;) https://en.wikipedia.org/wiki/Dark_forest_hypothesis
If they are truly that advanced, they certainly already know about us. It seems kind of arrogant to presume that we could detect them with our primitive technology and they could not detect us. Most likely scenario is that they don't care about us in the same way we don't care about ants.
It's why I'm 100% it can't be advanced life: we can't find life anywhere in the galaxy but we find advanced life in our own backyard (I know 120 light years is quite a lot)?
That might just mean that life is rare, but inevitably becomes advanced.
Even sending over a probe at 30% the speed of light would take 400 years, plus another 120 to hear back from it. No matter how interesting, for our human society it would be really hard to raise significant funds for a project that will only pay off in over 500 years, if at all. If they have similar lifespans, such a project might be similarly hard to get off the ground for their society.

That leaves radio communication, but the latest intel they have on us left earth around 1900. At that point we wouldn't have been able to receive anything from them. It's probably questionable if we would have picked something up had they sent a radio signal our way a week ago. Right now SETI might have a radio antenna pointed their way, but that won't last indefinitely, and these events are a bit hard to time from 120 lightyears away.

What if the advanced civilization treats us like the way we treat animals?

In my view it's better to stay away from the advanced civilizations

the ‘dark forest’ hypothesis.
We do have animal rights, don't we?
Do you want to be livestock? (Most animal mass is livestock).

We'd be lucky to be treated like bugs.

Yeah right. We like to think we do.
If we detected their planet, and they're significantly more advanced than us, then it follows that they know a lot about our planet already.
> What if the advanced civilization treats us like the way we treat animals?

As long as they don't treat us like we treat plants, it will be fine. I bet that that tomato didn't consent to be genetically raped with flounder's dna.

Or like Columbus treated the people who lived in South America or the Caribbean. How did that monster get a day named after him?
Many forms of life may be detectable using telescopes. A jungle planet will look different in many ways than an ice world.l, ways that are detectable. A billion LED street lamps would similarly make the night side detectable.
It's 120 light years away, sending a probe isn't going to do much unfortunately.
Not on human lifespans. But on species lifespans, we could probably establish contact.
4. dead or dying intelligent civilization

Slightly different than #1 assuming 'no life' means it never evolving

I can imagine a billion-year old civilization in its last gasps. Maybe it was a beautiful peaceful and technologically advanced civilization. Maybe it appeared and died before encountering any other advanced intelligent life from outside it's solar system.

Then again maybe it is dead from a nuclear or other catastrophic type of war.

A billion year old technologically advanced civilization in our own galaxy would probably be fairly easy to find as current models estimate that it'd only take a couple million years to colonize the galaxy even without FTL travel. Thus we'd expect to see various technosignatures scattered everywhere (including within our own solar system).

They'd have to either have advanced extremely slowly compared to us, such that a thousand years of our development are many millions of years of development to them or had some sort of extinction event that was so thorough as to render all of their stuff around other stars inactive (I guess maybe they might consider it extremely important to hide from developing civilizations though, in which case we probably can't even fathom what sort of hiding mechanisms they might have).

It's worth considering that with another century or two of development, assuming we don't face some sort of societal collapse, we'll definitely be capable of sending small probes to our nearby stars at large fractions of light speed. Given a couple thousand years without a collapse, we most probably can send self-replicating machines to colonize the galaxy like that. Even supposing that it takes us 100,000 years to get to that point, that's just 0.01% of a billion year old civilization's time.

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway.

2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (assuming that our broadcasting only started to be strong enough to notice 60 years ago). Then they might assemble something like a robotic attack army and send it over after, let's say 10 years. And if they are capable to send something half the light speed, then we might encounter our demise after 240 years more. So we still can enjoy our Earth 300 years or more if we don't destroy our livelyhood basis on Earth ourselves before that. Perhaps we could retaliate and send something back, but probably the odds are bad.

3. However there's the Loud Aliens And We Are Early hypothesis as well: maybe. There's life on that planet but not as advanced as ours. We will find more signs of life the next decades in that case. Then maybe send several robot probes. Contact could be possible after: 30 years of building the first probe, sending it over: 600 years (assuming we can reach 20% of light speed) and first reporting back 120 years, in total 750 years.

Caveat emptor: This is all speculation.

> Then they might assemble something like a robotic attack army and send it over

Why would they want to though? What do we have here that someone who could do the above couldn't get much easier otherwise?

To ensure that we don’t do the same.
"They might be hostile. So lets send an army of robots to wipe them out." But if the army of robots fails, then they'll definitely be hostile. That's... putting a lot of trust in your robots to win when faced with completely unknown conditions.
the dark forest requires a relatively simple cheap and effective way of sterilizing a stat system. if there is an easy way to do that then a first strike becomes a more reasonable first contract option.
Hopefully there is no way to drop a contaminant into a star to affect its output. A +/-10% change in brightness over a sustained period would probably neutralize us.
Planetary bombardment is almost certainly going to be the cheaper option there.

Less mass and energy overall. You will still have to accelerate it to a significant speed though.

But the environments that they evolved in and the environment we evolved is completely different. Earth to them would be unbearable for them to live on, and any resource they could possibly want would be readily available via asteroids. One last thing is the biology of Earth would most likely be toxic and incompatible with their biology.
But if we have the capability to destroy another civilisation 120 light years away, then we also have developed far beyond the need to, and they will know that just as well as we will know that.

I think it is impossible to survive as an exterminationist species to the point of having non-trivial interstellar reach. If you (as a species) were that inclined toward destruction, then you would not survive.

The counter arguments of, “Well, look at us!” are not convincing to me. We might well be that destructive, but we certainly have not developed to the point of non-trivial interstellar reach. I am not even convinced yet that we will get to the point of intrasystem mastery much less interstellar reach before we destroy ourselves. I hope we can overcome our barbarity, but there is no guarantee.

>But if we have the capability to destroy another civilisation 120 light years away, then we also have developed far beyond the need to, and they will know that just as well as we will know that.

That is a huge leap of faith and operating under a lot of assumptions not the least of which is that a completely alien intelligence would somehow operate in a utopian Age of Enlightenment and moral way and not in a way that we can’t even imagine or even understand because they are completely alien to us.

I’m of the opinion that intelligent life is probably extremely rare (in the one place where we know life exists it took 20+ million species and a full third of the age of the universe to make the single intelligent life we have…and we do our best on a regular bases to make ourselves extinct) and that is a damn good thing because I cannot see how intelligent alien life wouldn’t be completely hostile to other alien life and not immediately skeptical of the other’s motivations.

Divisive politics to the point of violence or even self destruction. Some pests you try to exterminate.
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Things have gone poorly for them, but they didn’t know it would happen like this when they invaded. In theory the USSR could have greatly benefited from a short war that gained them resource rich territory at minimal cost like the previous time they invaded Ukraine and annexed Crimea in 2014. https://en.wikipedia.org/wiki/Russian_occupation_of_Crimea

However, an alien civilization has little reason to invade a planet they can’t live on. Imagine someone suggesting we invade Jupiter,

I don't think Russia gained materially from that. While they ruthlessly exploited whatever resources they could get hold of in the Donbas, that of course that leaves the region much poorer so the have just concentrated wealth, not creates more of it overall.
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A thief doesn’t care about overall economic outcomes. Crimea may be worse off but that’s not necessarily relevant to Russia’s leadership.
Sure, leadership might gain via corruption but the parent I responded to was more likely speaking of the nation as a whole and not simply leadership.
I thought Crimea was about warm water ports?
I'm not sure how important the physical ports were, if they were important I suspect it mainly their symbolic importance.
> > Why would they want to though?

> Without wanting to turn this into a political debate you could ask this question about Russia attacking Ukraine

Reading you narrowly, I agree that of course you can always ask why an actor chooses a particular action. But I don't really understand your larger point, do you mean that all offensive wars are irrational? Because pointing out that wars in the history of planet earth have irrational causes is a long way away from explaining why an interstellar actor should attack whatever it sees.

> Because pointing out that wars in the history of planet earth have irrational causes is a long way away from explaining why an interstellar actor should attack whatever it sees.

I'm not explaining why they'd want to or wouldn't want to: I'm suggesting that it doesn't make sense to simply default assume they won't be hostile because we can't imagine reasons why they'd want to attack.

I'm picking the example of Russia/Ukraine because it's the most recent conflict example that I can think of where the aggressor's published reasons for attacking - at least to many observers - don't seem to stand up to rational scrutiny. You can have a debate about whether that's correct or not, and different people will have differing perspectives. The point is that aggressors can be aggressive for reasons that don't make sense or seem rational to others. Within the context of this conversation I am not looking to take a position on Russia/Ukraine: it's simply an example that most people will be aware of. Perhaps too current though to avoid an off-topic argument.

I explicitly didn't say anything about "all offensive wars" in general.

Your narrow reading is, from what you've said here, correct and I wasn't trying to make a larger point beyond suggesting that we don't have much of a basis to assume beings from another world will or won't be hostile.

If I were trying to make a larger point I would have stated it explicitly. One of my pet peeves with online discussion is a culture of implication (i.e., people choosing not to speak plainly) that leads, in many cases, to other comments being overread/overinterpreted when they were never intended to be. Hence, I would have chosen to make the wider point explicit rather than leave it to chance, but it seems like I wasn't clear enough in any case, for which I apologise.

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If they are used to propaganda where every enemy is stupid and ever allied plan works they don't. But in real life you can be genius and a bad person at the same time
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"Eschew flamebait. Avoid generic tangents."

https://news.ycombinator.com/newsguidelines.html

Respectfully, I object. Evidently I wasn't clear enough, for which I apologise, but I've explained the intent of my comment in more detail in response to @SiempreViernes' sibling comment. Hopefully that clarifies.
We have to go by effects, not intent, which means the burden is on the commenter to disambiguate their intent. If the topic is divisive and the intention is not inflammatory, that may require some care. That's why the HN guidelines say "Comments should get more thoughtful and substantive, not less, as a topic gets more divisive."

More explanation on these points in case anyone finds it helpful:

effects, not intent: see https://news.ycombinator.com/item?id=28932445 and https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...

the burden is on the commenter to disambiguate: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...

Read more about the Dark Forest Hypothesis. I don't mean that this hypothesis is valid but it makes sense to think about it.
The mass isn't directly correlated to the gravity (~5-6G assuming rocky planet density in this case) and the amount of atmosphere also isn't guaranteed. It might have an atmosphere that merely doesn't extend as far into space. Basically an anti-Venus since it has similar mass to earth but a much thicker atmosphere.
Of course. It's all ballpark.
How would we even get off planet if gravity was 5x what it is, we’d have no chance?
Presumably when we're talking about actually traveling across the galaxy at anything approaching the speed of light, we've developed something more sophisticated than "burn a bunch of fuel" to both get to space and travel through it. Anti-gravity seems the most likely candidate, but who knows if that's even possible.
When I hear about life on alien planets I always think about bacteria, virus and other micro organisms.
That's probably the case for the majority of planets, also even with multicellular life there is no guarantee that intelligent life would evolve. Earth went 4.5 billion years with 700 million with multicellular life and imagine if early hominids got wiped out, would another intelligent species follow our trajectory?

Also I would like to point out that the vast majority of planets we detect happen to be around red dwarf planets since we need 3 transits for a positive detection which would require years for larger stars. Additionally to do atmospheric spectroscopy the solar system needs to be within a perpendicular line-of-sight of our solar system.

So keep in mind the planets/solar systems we are studying do not represent the typical solar systems around exo K/G type stars.

600 years at 20% speed of light. So, we are not going to visit the planet unless we find a way to create worm holes at will.
If you think as a species, then 600 years is nothing.

If you think as an individual, then 600 years is dismaying.

> Then they might assemble something like a robotic attack army and send it over after

Violence is undeniably primitive behavior.

It amazes me how many humans assume that other species would advance technologically to the point of interstellar travel while still holding on to primitive roots.

It's extra surprising from a community like HN where an abundance mindset is the status quo.

You're setting up a binary between advanced/primitive; I would hesitate to speculate that they would conform to our ideas of these concepts.

The other thing to consider is, we might perceive some actions as violence, while the other species may not view it at violence at all. We may simply be materials that can be reallocated for other purposes, just like how humans often view living things in our environment.

Technological progress can be used for good and evil. It’s very plausible that a society with advanced technology could still act unethically. We have examples of that right here on Earth.
It's a complete myth that far-away planets can pick up our radio signals from background noise (especially from our own sun). We can't even talk to the nearest star system at 4ly.

https://space.stackexchange.com/questions/22617/can-we-commu...

This misconception fuels the false "why are we alone" question that implies we would have detected intelligent life if it's there. Not so fast.

> Perhaps we could retaliate and send something back, but probably the odds are bad.

Only took 60 years from first flight to man on the moon.

300 years is plenty long time.

Suppose we crack true general artificial intelligence, nuclear fusion, ability to design self-assembling beings with DNA compilers, advanced material synthesis then we could very well launch a retaliating attack.

In principle yes, it is enough time, however it is important not to underestimate our novel hostility to doing anything both meaningful and new.
As the mass is 10 times Earth, gravity will be much stronger. So the invading aliens might be of a different size to us. To their disadvantage. The outcome might be likely to be ...as hinted in this old Dutch commercial from an insurance company - https://youtu.be/XcdC-Y2dQto
120 light years away.

If there was life out there, similar to us - could we detect their radio and television signals over this distance?

If we could get a positive confirmation of just anything living - even if it's just oceans of plankton - then that would revolutionize our understanding of the universe.

Actual, viable, recognizable lifeforms of extra-solar origin changes the inputs to a lot of our ideas about where and who we are pretty substantially (also some rather unfortunate possibilities about the great filter).

of course. photons do not experience time or distance, and are probably ageless
They do, however, experience the inverse square law.
When I read such PR it feels that someone need a budget approved and no accountability : "here is something cool that nobody can check, but hey we could explore this for a couple of millions, can you sign down here"
Huh? Most of the "cool" stuff is speculation from readers like ourselves.

If you were on the budget, Galileo would have never gotten money for a telescope.

Nobody can check? You can file a request for a time slot on webb if you have proper reasoning then compare your atmospheric composition findings with nasa own findings that they posted also they never claimed that there’s life they said “some astronomers believe that these worlds are promising environments to search for evidence for life on exoplanets.” Also they have other sensors on webb that have no been pointed at the planet yet so I don’t think they will need any money for this purpose yet. Heres the original post https://www.nasa.gov/goddard/2023/webb-discovers-methane-car...
Data is open, you can check. Hell you can even propose your own time slot of webb if you want.