We probably will need IPv10 to connect all the dots in the sky!

But IP is not designed for high-latency networks, so this only really matters if FTL communication is invented.

There is hope. Now quick, someone post a cat pic and a relevant gif.

Edit: Not complaining about the downvotes, but guys, this is the internet, not work. Loosen up. Smile for once. It's good for you, and confuses people.

Assuming an acceleration of 10 m/s^2 (similar to Earth's gravity), it will takes roughly one year to accelerate to a speed close to the speed of light were relativistic effects occurs, and you will need one more year to decelerate.

Is there something uncivilized about the Arab conquest of Byzantine lands? Had the Kepler 452-b-ians been observing Earthians but a few hundred years prior, they'd have seen the Romans doing much the same to expand their own empire. And the Arabs did quite a good job to not only preserve the Roman intellectual and scientific state of the art, but to contribute their own advancements of those fields.

There's a quite a bit more human energy going into war and destruction right now than into "peacefully collaborating among mankind to discover and explore planets."

If they were observing us today, they'd still see plenty of war and destruction.

It just so happens that a fraction of the worlds population lives under "peaceful" conditions. That's not universally true.

Source: I'm both an Arab and a Muslim.

We don't call the Spanish conquest of the Americas a Christian one even though they were Christians who ultimately converted everybody to Christianity.

What irritates me greatly is when historians refer to the Muslim scientists of the Islamic Golden Age as "Arabs", when most of them were not Arabs at all. It's such a simpleminded and sweeping generalisation that clearly shows the thoroughness of the so-called orientalists.

I agree with you about the second point. I guess it's due to the fact that they wrote in Arabic and many of the people they actually belonged to no longer exist (for example al-Khwārizm was from a Persian family but born in what is today Uzbekistan - I actually visited his hometown :)

To me it's strange to ascribe such areas of study to the religion. What does Islam really have to do with optics besides Ibn Al-Haytham being a Muslim? No one ever ascribes enlightenment science as 'Christian science'.

Hence the 'weaker' nation feels deprived of its history when its proudest moments are appropriated away.

Err, the Byzantine empire was still going strong for 6 centuries after that (and still existed, but not in a good shape, for 8).

It never got overrun by "barbarian hordes", but it did have a run in with thieving "supposedely christian horders" on their way to the Crusades in the 12th century, and was finally overrun by the muslim Ottoman empire in the 14th century.

This means that merely achieving orbit would be approximately as difficult as launching a probe on a Hohmann transfer orbit to Mars is. (Except that such a launch vehicle would need nearly twice the thrust/weight, cutting down the mass ratio even further.) It is not unreasonable to think that a species on such a planet would have never seriously developed space travel.

To head off the common rebuttal of "maybe they wouldn't have any interest in it," with more advanced technology smaller and smaller groups of individuals would be capable of instituting such a project, to the point where any high school kid with a synthetic biology kit and some toy rocketry kits could colonize the entire universe (owing to relativistic effects). You'd have to assume their society underwent some kind of massive convergence of social norms away from any individuality such that no few members of their species ever had both the capability and desire.

The entire plan is mostly laid out by: http://www.tedxvienna.at/watch/why-aim-for-the-stars-when-th...

Progress is the exception, not the rule, so far in human history.

You're either cherry-picking your intervals or have a very weird definition of "progress".

If you don’t stick with Hydrogen Carbon Nitrogen Oxygen you’re going to have a much harder time finding what you need to grow on earth. For extra solar stuff even those might be hard to find.

If you do stick with HCNO it's hard to get a leg up on nature without simply making a few minor improvements which has limited value outside specific situations. There are also a lot of tradeoffs with binding energy etc.

1.https://en.wikipedia.org/wiki/Zoo_hypothesis

2.http://www.odditycentral.com/travel/north-sentinel-island-th...

If they took 100 years to get to the next star system 5-ly away and then 500 years to populate that system enough to start a new colonization, that's just ("just") 168,000 years to be here. Given a 2 billion year head start, that's easy.

Cathedral building in the middle-ages was a multi-generational 80+ year affair and some of the Pyramids took even longer IIRC. So societies were/are definitely capable of working on ~100 year missions :)

Maybe a generation ship needs to have some sort of 'cathedral-in-the-sky' religion connotation in order for us to commit to building it. Sounds like an interesting idea for a sci-fi plot!

But we've only been working on that for a few decades. 2 billion years is a lot longer. If there is a civilization there at all, it's extremely improbable that it hasn't figured out how to do exploration on a scale of thousands of light-years.

I suspect that's unlikely, even if there were advanced life there for 2 billion years.

Why do you think so? "Continuity" doesn't have to be having the same government or the same political structure, or even the same physical form (the article itself talks about uploads and nanomachines). It just means continuity of technological development. It doesn't have to mean steady progress either; our civilization hasn't had that, yet in ten millennia or so we have progressed from basic agriculture to space travel. For this planet, we're talking about two million millennia, or 200,000 times the time we've had. All the variables we've observed in our civilization's history become rounding error on that timescale.

Perhaps no civilization of any sort has ever developed there. Maybe conditions on the planet are inhospitable, perhaps evolution simply never went that way. I think people tend to assume that evolution naturally leads towards more intelligent creatures, but that's not true. Humans are a very very recent development on our planet, in geologic time scales, and our early existence was pretty improbable.

Perhaps civilizations have existed there, but never achieved technological advancement. There are still tribal civilizations on Earth that are using 50kya technology; there's no guarantee that a civilization must develop science and technology.

Perhaps it has had civilizations with similar technological advancements to our own, but they have been destroyed or set back by any of a number of things: extinction-level impact events (could easily happen to us), disease, warfare, or resource shortages. Maybe, for some reason, they never developed easy access to a high density fuel; imagine if humanity had tried to go directly from steam engines to nuclear or solar power because oil didn't exist or wasn't easy enough to find or its significance was never understood.

Perhaps they reached a level of technological advancement far, far superior to our own, but they never made an effort to explore the cosmos. The vast majority of people on Earth right now don't see any point to even exploring other worlds in our own solar system; that mindset could easily dominate for the rest of mankind's existence. Maybe we assume that there is some kind of shortcut around the speed of light and there isn't and, no matter advanced a civilization gets, there simply aren't enough volunteers for a 10,000-year journey to another tiny little planet that may or may not harbor life.

Perhaps all of these are wrong, but they simply visited Earth a million years ago and found it to be entirely uninteresting and haven't been back since. Maybe their civilization has even ceased to exist, and our civilizations will never ever cross paths because we missed eachother by a few minutes in geologic time.

I'm generally optimistic about the chances of advanced civilizations elsewhere in our galaxy, even relatively close by, and entirely pessimistic about our odds of ever being able to interact with those civilizations in any meaningful way.

Or that the distances and difficulty of transporting anything very large or complex between star systems turns out to be just too great of an engineering problem for any life form. The energy required to move a life-sustaining amount of mass between stars is mind-boggling huge and beyond our own technological capabilities for the foreseeable future ( we only anticipate interstellar life is a possibility by assuming our technological growth curve will continue unimpeded and then guessing there's life out there further along tha us, which may not be accurate or possible).

Or that they are indeed spreading but doing it in a way undetectable to our technologies we're looking with and we just didn't come up lucky enough to be directly contacted by them in their spread (yet?).

Or maybe they developed a Matrix-like utopia, a self-maintaining and long lasting support system and stopped outward appearing progress?

Or going in another direction, perhaps we really are inside a simulation and $life_bearing_planet is set to 1.

The hypotheticals are nearly endless and not necessarily due to overtly negative outcomes.

I wouldn't have expected every possible situation to have occurred given the finite history of the universe.

But I really have no idea what I'm talking about, so my request is serious.

So we could be in ZOO experiment. Other civilizations want to see if we are capable of evolving and joining them so they make sure we are not disturbed by other life out there because if we discover intelligent life, we will freak out. We might start fighting for our survival and it could affect our evolution to higher species.

We could also be a part of some computer simulation (with enough power you can create rules with particles and simulate the universe). Maybe somebody is trying to answer this question: If you create a big enough simulation, will be the simulation able to figure out it, it is being simulated?

Or maybe everything that we see is true but it is just impossible to overcome some physical limitations. We assume there are no limits and everything is possible and one day we will master it. But what if communicating and traveling through universe is nearly impossible? Maybe there are limits that we don't know about yet.

Maybe every civilization reaches point where they know the answer to everything and they don't see a reason to live anymore or they leave the universe and move somewhere else.

My point is that we assume something that will eventually turn out false and everyone will be surprised by the truth.

Imagine how much more wisdom (besides technological advancement) the average humans will posses in just 200 years (provided things evolve like they have been evolving during the last century minus the wars ).

What wisdom and knowledge will we have in 1000, 2000, 50000 years (again, provided we are still alive) ?

Maybe there is no need to physically travel through light years of space, maybe the 'truth' is much closer - right inside our own minds.

In just a couple of decades we'll be able to build simulations which simulate all our senses and are just as real as our 'current' Universe - enter there and take a pill which makes you 'forget' about this reality and you can basically live another life without knowing about your current one.

What if our current life is the result of such a 'game' which we entered and forgot about the 'outer' life. What if we're level 64 deep in such a simulation within simulation ? :)

So many possibilities, but hopefully we'll somehow figure them out ..

If you have facts to prove him wrong, feel free to reply and publish them.

The little boy in me so wants me to be wrong.

Our planet has life in all kinds of niches. Why would an Earth-like planet not be overwhelmingly likely to have life on it? (I am an engineer also...)

Don't get me wrong, I'm not saying that Earth-like planets generally won't support life. I have no idea how many will. It just seems unlikely that the first one found happens to tick all the relevant boxes.

Having said that, the fact that they've found one so quickly, relatively speaking, seems like a good indicator that there are an awful lot of good candidates for life-supporting planets. The more there are, one would assume, the more chance that some will have everything in place.

But then again, we could just get lucky and hit it first time. Which would be stellar (sorry).

The composition of Earth's atmosphere was pretty similar to Venus and Mars, before photosynthesis changed it to the current composition.

There is good evidence that life apeared on earth more or less as soon as it cooled down, so there is just as much reason to think that this new place may have life as not.

However, by the same reasoning it seems to me that the life may be bacteria like!

[The Fermi paradox: We're pretty much screwed...](http://imgur.com/gallery/Wtog9)

It's like, nobody has considered that advanced life might not even feel a need to live on planets at all. It's expensive to get resources from, and there's a near limitless supply of easy to get smaller debris.

Additionally, the difference a 2 billion year head start could make is hard to imagine. One thing that's not hard to imagine is that they don't live in meat bodies for most of that time. They could easily be machines or virtual, and then would look and act nothing like anything we're looking for.

Any space habitat of any plausible size will be completely undetectable, or at least indistinguishable from a planet. And I would think they'd be much smaller than that.

And structured radio? Lots of possible reasons not to see it. One, possibly not using radio. Two, encryption. Communication will likely look like noise. But even so, the distances involved means long range transmissions will need to be very directed and narrow beam. And even then, it's only a few light years before the signal is undetectable. I would suspect any really long distance communication would be bounced through relays. Also, why? You have to wait years for messages to go around. All of this means no, we're not likely to easily find stray radio signals.

And this is without getting into Dyson spheres and other efficient but detectable technology.

Yes, of course. And the heat of a star will make that heat completely invisible in comparison.

The "spectra" that heat would be vented at is infrared, which is infrared no matter the source.

Say you had some gargantuan fusion power harnessing space station in deep space. lots of assumptions here about alien cultures, but this is likely the easiest to detect. They will do whatever they do with their energy, and then vent the waste heat. That heat will be infrared. What does a dim infrared source look like (if even visible at all)? It looks like a brown dwarf. But this is assuming a lot. It assumes some alien would even build brown dwarf sized space stations. We don't know if or even why they would do that.

How do we know this? Because astronomers see these every single night and have developed sophisticated filters to remove them. But by checking how the source is moving it is quite easy to tell if source is local or not, and sure enough all these artificial sources come from satellites, the troposphere, or an unshielded microwave.

It is actually remarkably difficult and a challenging problem in itself to create a communication mechanism which looks like a natural source. It defies imagination to think that every single intelligent species out there has purposefully masked their existence in such a way, including giving up useful technology like ground control radar or mobile communications.

Just think about it. The signals are going to be so weak by the time the photons get here they will be indistinguishable from the CMB.

I'm sorry, but that's way off.

Our current telescopes can't even see the majority of the exoplanets in our galaxy; we are made aware of their existence by observing the behavior of their host star (wobbling/dimming). Unless something is extremely close, unfathomably enormous, or emitting/reflecting large amounts of electromagnetic radiation (light, radio, etc.) that isn't bent/filtered/reduced to noise, then we are completely unaware of it.

https://en.wikipedia.org/wiki/Dyson_sphere#Search_for_extra-...

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

Maybe there are other channels of exploring spacetime than just the physical reality. Maybe that's where all the advanced civilizations reside.. Like the place we are in before we are born or after we die...

1 million years of mind evolution should not only bring advanced tech, but also advanced wisdom and understanding of who we are and what we are doing here. I doubt that expansion to all possible planets is the ultimate goal, the mystery must go much deeper than that ;).

Edit: I've said that self-interest isn't exclusive to Earth, without providing evidence and I don't have any; I should have said that self-interest isn't exclusive to humans, the simplest forms of life (bacteria, as an example) make war also.

Any of the hypotheses we discuss in this thread (whether they are over-confidently stated as facts or marked as speculative) are inevitably deficient due to data derived from a sample size of one.

But what I find most amusing is that when I was a kid "science" was saying "but we don't know if any other star even has a planet!" and to me as a kid it seemed preposterous that other stars wouldn't have planets. And now of course we know that pretty much ever star has at least some planets. The unusual case is no planets.

Similarly with life, it seems ridiculous to think that somehow this planet at this time was the only place anywhere that sentience emerged. So it really makes me wonder, why the heck aren't we already talking with them?

What is it that keeps intelligent life that originated on other planets from communicating with the intelligent life living on this planet? Why won't they talk to us?