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Coming up next on the History Channel: Preliminary scans indicated 'Oumuamua was just a lump of space rock. But could it be... a derelict alien spaceship?
Further investigation revealed that it was indeed a space rock, but.... could it be some sort of projectile sent to obliterate humanity?
Thankfully, the alien race that sent it isn't yet good enough at orbital mechanics.
Lets hope its not a reaper corpse that never ends well :-)
"Plane change maneuvers are expensive"
I wish that book had a better ending.
Which book is that?
Seveneves, if I'm reading the OP correctly. By Neal Stephenson.
Anathem, Neal Stephenson. (Seveneves also mentions plane change maneuvers but Anathem has this quote repeated verbatim several times and is closer to the topic at hand. Then again, more people seem to be disappointed with Seveneves' ending, so who knows.)
Overall, it's quite a positive ending. I wonder whether someone dared him to write something dystopian, but with an upbeat ending.
I wish that book didn't have a part three.
Me, too. My background is biomedical, so i spent most of it thinking "epigenetics doesn't work like that!"
As a layperson I felt like the time frame in which they were suggesting this extreme genetic shift would happen seemed a little much. The pace of the book was also completely different.
Obviously, this indicates they're using technology far exceeding ours that's undetectable to our sensors.
It could also be just a dead spacecraft, than was once operational but is no longer so. That could also be why it's tumbling now, whereas once it may have flown in a more aerodynamic fashion.
it's obvious what you're describing but just wanted to point out that aerodynamic is a poor choice of words to describe an interstellar body :)
If it's tumbling to provide artificial gravity, then the crew needs something like 8.94595e-7 g to feel comfortable.
"Flui-dynamic"? How best to generalize from air to any fluid?
Maybe it just rotates to create artificial gravity.
Obviously. Radio signals aren't exactly a good way to communicate through a large space. It takes forever!
They mentioned that they're scanning a frequency range from 1 to 12 GHz.

Why that range? And what if it's transmitting at 0.5 or 13 GHz, or 500 GHz? Would that show up, just weaker or..?

As a radio-astronomer: 1. Well, few radio-telescopes have instantaneous bandwidth as wide as a factor of 12 -- they are usually optimal on a narrow region, and therefore hoping that another group with instruments optimized for lower/higher frequencies will do the job 2. Lower frequencies require larger antennas to achieve useful gain. It is more likely that they would go higher than 500 MHz vs lower. Also, dispersion (correctable with a position solve) and scattering (not correctable) eventually become problems with low enough frequencies and long enough distances 3. If we observe at the wrong frequencies, it will most likely not show up. RF filtering and antenna response will ensure that.
What if it's shields are up?
I'm kind of glad to hear that to be honest. It's already too far away from us and going too fast for any spacecraft that could currently be built to reach it. It would have been a very cruel joke if the first opportunity for interaction with extra terrestrial intelligence flew past us so unceremoniously.

Of course it's certainly disappointing that it isn't an alien spacecraft, but would have been doubly so if it were and we missed our window of opportunity.

I dunno I think if it were an alien spacecraft we should just keep our heads low and not draw any attention to it. Our first window of opportunity might be our last.
I've gotta disagree with you on this. Personally I think intelligent life is probably very rare in the universe, the sheer number of factors that need to go right for it to arise, and then the sheer number of factors that need to not go wrong for it to continue to exist mean any intelligent life out there is probably going to find us way more valuable and worthy of co-operation and interaction than say destruction of us for the measly resources of Earth, or enslavement (although I guess enslavement could be possible).

I do also have faith in the "humanity" of any interstellar life that may exist out there, after all a society based on oppression tends to be rife with conflict, and societies rife with instability and conflict don't tend to last. And in my view it would be very unsustainable for any life to maintain that sort of conflict, and at the same time hope to extend a society out into the universe.

Nothing ventured, nothing gained. I think it's worth the risk.

The last thing I would want for an alien life is to be humane. We have not really been great in our interactions with other cultures throughout history and they were of the same species as us.
I think you're not interpreting the word "humane" correctly. It's possible for humans to behave in an inhumane manner. In fact it happens a lot to this day. That doesn't mean GP's definition of "humane" is wrong.
I am aware of this.

I am not a native speaker, so the dichotomy between the sense of this word and our most common behaviors as a species has always felt unsettling to me.

I kind of like this word, I would love to live in a world where this is a perfect descriptor for our species.

Back to the topic at hand, while it would indeed be marvelous to find benefactors from the stars, all the other possibilities are chilling. From cosmic horror to simple warmongering, there are so many ways it could go irremediably wrong.

I put humanity in quotes because I didn't really know what else to name it when talking about some other form of intelligence. I guess I'm talking about that part of our society that craves peace and stability, that has enabled our continued development up to this point. Certainly throughout history we've seen unimaginable cruelty inflicted on "less civilised" societies by colonial and imperialist societies. Hopefully any intelligence which has reached the development of an interstellar society would have those same qualities, frankly I don't see any other way for it to sustain itself.

Imagine we came across anew form of intelligent life on Mars, would we exploit and enslave it? I'd like to think living in a global society would prevent such atrocities, at least in the modern era, and hopefully beyond. And I think any society in an interstellar context would behave the same

We probably wouldn’t exploit it as long as access was hard. Once space travel becomes more common though, I think we might have a situation like Star Wars where the far away worlds are basically left to their own devices since it would be a huge pain for an earth centered society to enforce laws...
But the society need not be based on internal oppression, to be an adversary to us: I don't think the kingdom of Castille in 1492 necessarily was a beacon of stability and lack of conflict; yet it financed an expedition westwards.
That is true, but I don't think fair parallels can be drawn between a southern European empire in 1492 when humanity was still discovering itself and it's place within the universe to an interstellar society. Society matures in much the same way as an individual does, albeit on much longer, slower time spans. Can you seriously imagine an interstellar society (which I truly believe would be a democracy, as I see no feasible way an imperialist dictatorship would be possible with that sort of decentralization of society) having the same ambitions as a pre-enlightenment imperial society? I think the goals, desires, hopes and pursuits of that society and the individuals that compose it would be fundamentally opposed to that sort of expansion and enslavement.
Democracy isn’t something that automatically makes you a space faring civilization, neither is it necessary. The Roman Empire got pretty far while enslaving millions of people. It’s not a stretch to think that the Age of Science could have happened under Roman tutelage had it not met its unfortunate demise
What if intelligent life is rare because at some point some other intelligent life set up a systematic process of keeping the universe clear of it?
You've been playing too much Mass Effect 2 :^)
I've actually never played any Mass Effect...
People are fixated on that, but it's not the only solution to the Fermi paradox
Then we'd certainly have evidence of this genocidal society no? They'd definitely be actively looking for other intelligent life forms, and if they were systematic in eliminating it, they'd have to have the infrastructure to do so which we'd be able to detect. After all you catch more flies with honey than vinegar, any life form like that would have the interest in finding and eliminating intelligent life before it becomes to big to be a threat, which would probably lead them to coaxing other intelligent life forms into making contact. No, I don't think this is feasible in reality, nor is there any evidence beyond "but what if" for that possibility.
Maybe the only cosmic infrastructure required would be listening stations and the ability to steer big rocks to sources? The listening stations would be hard to pick out. They could run a 'reverse' fermi equation of sorts and figure out how fast you need to detect and extinguish signals to keep the universe clear. Would the extermination look anything more than unfortunate random collisions? Do we actually have enough data to calculate if collisions are above some noise floor of random happenstances?
On the flip side, the conditions required for life to reach interstellar technology are so rare that life-bearing worlds like Earth are highly coveted.

A planet where you can set up a city and not have to worry about micrometeoroids, radiation, atmospheric composition? Just sleep out under the stars without a suit repair kit handy?

That’s worth killing for!

Wiping earth clear of humans and still having a habitable planet left over would require far more resources, risk, lives of your own and time then simply building a few colonies on planets like Mars.
Pfft! Smart aliens just send a couple of stealth probes, figure out our biology, and in short order program a simple virus that is dormant but highly contagious for about a year and then when incubation is over kills within 24 hours.

Ironically it’s not far off what was done to the Americas.

War is only an option when the sides are more or less evenly matched. We would not be anywhere near evenly matched with an interstellar civilisation.

If you can make the trip you can probably survive in space definitely. I'd be surprised if truly space faring civilizations really like gravity wells. Getting up and down them isn't cheap (although with plenty of effort it can be made cheaper). Everything is all stuck together, if you can find an asteroid of the material you want mining it and moving it for sale/manufacturing should be so much cheaper than dealing with moving a bunch of unrelated materials away under gravity.

In space you'd be able to move arbitrarily large objects with just an accelerator, map of the solar system and a transponder. In a gravity well you need a lot more and way more $$$ if you want to get it up the well.

Then again I have no training in the subject.

Rare per-star or per-planet, but in our galaxy there are an untold number of stars. In the "universe" as a whole, whatever numbers you throw at the Drake Equation the answer is billions of civilizations.
As a counterpoint, I'd argue that conflict can act as a "force multiplier" of sorts.

Every large war in our history has caused leaps in technology. Even on a smaller scale we treat conflict and competition as a good thing that promotes innovation.

Life as we know it "craves" and thrives on conflict. And if that's a universal truth, then any other civilizations we meet could as well.

Excellent point. Wars have (albeit morbidly) allowed for drastic changes in all aspects of human society as well. But maybe a war based society can only progress until it invents planet destroying WMDs. After that the cost of war becomes intolerable to progress
It doesn't matter. No matter how convincing your argument is, we can't afford to risk the entire world on you being right. The stakes are too high.

And I think you are very wrong. Aliens don't need to be anything like us. Don't anthropomorphize them. They might have nothing like our morality or care for other sentient life forms. And just see us as a pest and potential future competition to snuff out.

Or if they do have morals, they could be completely alien. When the Europeans discovered the New World, one of the first things they did is try to forcibly convert the natives to their religion. They justified conquering and ruling over the natives to stop their savagery and impose their values and laws on them.

One Important thing to note was that while religious undertones certainly existed the main goal of colonizers was economic. So I wouldn’t be surprised if the first alien ship to arrive on earth would be an exploratory mining ship trying to basically mine earth for water/minerals and would wipe out anything inconvenient such as existing life.
You might be entirely right, but the universe is a big place. Estimates of the number of stars (called Sagan's Number[1]) are on the order of the 3 x 10^23 (300 sextillion[2]). Even if only a tiny fraction of a percent of them had worlds with intelligent life, there'd be a lot of it out there. The bad news, though, is that it's still hard to travel, or even send transmissions, so it's just as likely we're doomed to stay lonely.

(I tend to share your optimism about the odds of other intelligent life being good-natured; we've come a long way in the last 2,000 years, by the time we're out in the stars, I'd like to think we'd all be Bodhisattvas).

1: https://en.wiktionary.org/wiki/Sagan%27s_number

2: https://www.npr.org/sections/thetwo-way/2010/12/01/131730552...

Good luck with that considering how much RF we're blasting out into space(you can make contact with the ISS/AmSats on a 5W handheld + yagi antenna).
In The Killing Star, it was Star Trek that sealed Earth's fate. Humans came off as dangerous know-it-alls :(
In the Dark Forest, we could get lucky given how faint and brief the peak of our RF emissions have been. We’d probably have to be close to “someone” looking for signs of life to give ourselves away now. Still for all that we know the relativistic bombardment is already en route, or a dual-vector foil.
Maybe that "cigar-shaped" rock was a near miss ;)
This reminds me of Liu Cixins "The the body problem"-triology. If you haven't read it yet you should have a look.
Dark Forest Deterence. I'd be interested to find out what % of HR readers HAVEN'T read this trilogy considering how much it comes up in conversation on these forums. I'm willing to bet it is a VERY high % compared to the average reading population.
I started reading it and found it fairly poor quality sci fi so I stopped somewhere in the first book. I think the bit where they slice a passing ship with newly invented nanowires smacked more of a comic book or 50s golden age sci fi than the sort of “proper” science fiction I’m used to these days. That and the way the characters seem to have such simplified motivations. It’s just not good fiction - and science fiction has to also be good fiction.

Edit: wow, downvoted within a minute for not liking the same sci fi books. That’s a new low in HN groupthink.

It wasn't me! Personally loved the series! I'm always on the lookout for more "proper" sci-fi, so please share! I've been binge reading hard sci-fi this year and can't get enough. And yeah, HN is a tough crowd.
There’s so much awesome SF out there... it depends what you like!

Personally, in very different styles, I found pretty much everything written by Iain M Banks excellent (start with Excession or Player of Games), I enjoy John Scalzi’s humourous sci fi space operas a fair bit too, Peter F Hamilton’s Reality Dysfunction trilogy was pretty decent... I’ve loved most of what I’ve read from Charles Stross but particularly Accelerando, Greg Egan’s Diaspora was awesome, like a modern day Childhood’s End (read that too if you haven’t, though it’s aged badly). Cloud Atlas is sorta science fiction and amazing. I’ve yet to not enjoy any book by Cory Doctorow - start with Pirate Cinema. The Windup Girl by Paolo Bacigalupi was excellent.

This should be enough to get you started!

Thanks for the list. All new territory except Cloud Atlas which I enjoyed immensely.
You should give it another shot, second book is pretty good, third one is great.

It's not Quantum Thief, but it ain't have bad either :D

Do the characters get a bit more complex than “humans killed ppl I loved so now I’m going to plot to end all human life”? Because it was really hard to suspend my disbelief on that one. People just don’t behave in unidimensional ways like that. And they forget trauma, fall in love, gain contrary motivations. Humans are complex creatures.
"Don't be snarky." "Please don't comment about the voting on comments. It never does any good, and it makes boring reading."
Revelation Space explores the concept better.
It's going pretty fast, but it'll slow down a lot as it crawls back out of the Sun's gravity well. It'll only be 100 AU away in 2034 and 1000 AU away in 2196. Which means that human made spacecraft absolutely will visit it in either the 21st or 22nd centuries. We could actually pull off a flyby mission within the next two decades or so if we dedicated enough resources to it. And as our launch technology improves over time, that only gets easier and cheaper.
This is a good point. The Voyager 1 and 2 spacecraft are only 141 and 117 AU from earth [1], and they were launched 40 years ago. I have always thought that the most likely fate of the Voyager spacecraft is that they will be stolen -- not by aliens, but by humans of the future. Their positions and trajectories are a matter of public record; everyone will know exactly where they are, and the spacecraft themselves as well as the golden records could be of great value to wealthy collectors of the future. Consider how many times the wreck of the Titanic has been visited/looted over the past 20 years, and when it first sank no one thought it would ever even be found, much less visited.

[1] https://voyager.jpl.nasa.gov/mission/status/

So if this was the movie Gravity, we could just scoot voyager over to see it as it passes by.
> It would have been a very cruel joke if the first opportunity for interaction with extra terrestrial intelligence flew past us so unceremoniously.

It won't leave the solar system (Oort cloud) for 20,000 years. I'd hope our technology improves enough to be able to catch up in that time.

> I'm kind of glad to hear that to be honest...

Whaaat! Come on. Surely you'd gladly take the disappointment of missed opportunity for the absolute earth shattering wonder of proof that we are not alone.

The most momentous discovery would be that it is indeed an alien spacecraft. Whatever we could have gained from a close inspection would pale in comparison.
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First thing what I do if it is my spacecraft i will not send anything until I'll far away enough to not be detected and probably won't point transmitter to planet which are investigated (I know that signal can be reflected back from cosmic debris, but who can send rock to other solar system won't have problem to calculate signal path which doesn't point to us)
ego blow, we're not even probe worth
it is on scout mission, invasion is now imminent
Maybe it's just one stage of a rocket that is slowing down?
take me now. this world is too crazy for me. :(
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> The cigar-shaped object ...

All they have is a light curve, right? No imaging, right?

If so, "cigar-shaped" is just speculation.

It rotates, so its brightness changes over time. From examining this data they can draw some conclusions about its shape.
Sure, but "some conclusions" is a long way from "cigar-shaped".
When a factual mistake is called out, it's probably better to do some research instead of doubling down.

>The astronomers figured out its elongated shape when they noticed its brightness varied when it rotated every 7.3 hours. When the asteroid’s long side faced the Earth, more of its surface area could reflect sunlight, making it more visible to us. And when the tip of the rock faced us, it was a very dim point of light.

>“What we found was a rapidly rotating object, at least the size of a football field, that changed in brightness quite dramatically,” planetary astronomer Karen Meech, who led the University of Hawaii team, said in a statement. “This change in brightness hints that ‘Oumuamua could be more than 10 times longer than it is wide — something that has never been seen in our own solar system.”

Source: https://www.pbs.org/newshour/science/a-cigar-shaped-asteroid...

Statement from the team in Hawaii: http://www.ifa.hawaii.edu/info/press-releases/Oumuamua/

You would be surprised how much we can infer with p>0.05 based on information that looks scarce from the outside. Much of what we know about the universe is found from surprisingly simple sources.

The article makes a much more limited claim than what the headline suggests:

"the search for alien signals has so far found nothing in the 1.7 to 2.6GHz range"

Scanning continues.

Maybe it's the interstellar equivalent of throwing a rock at someone's window to get their attention? An alien race could have used a gravitational slingshot to send it our way.