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Mystery of interstellar visitor 'Oumuamua gets trickier

scientificamerican.com

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Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#191

Post by postalrat »

nvrspyx wrote: post #83
burtonator wrote: post #71

Earlier quoted context omitted.

> Realistically, though, it's too much of a coincidence that such a probe would first arrive so soon after we gained the ability to conceive of it. It is based on TIME but our conception of it would be independent. I think a lot of what's part of the drake equation is merited on overlap. It's entirely possible that other civilizations have been created and died out LONG before mammals even evolved. IF you factor in j…

> I think it's plausible that a god would not want to talk to another intelligent civilization. Why would we? We would be to a god what bacteria is to us. That may be because we can't even perceive bacteria, but if we go a little bit bigger and you could have a conversation with a dog, cat, deer, or any other animal, I bet you would. I know I personally would just to understand how those animals think and the differe…

It's hard to conceive of an intelligence as much above ours as we are above bacteria cell. But if such a thing did exist why would it want to communicate with us?

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#192

Post by gorgoiler »

kentonv wrote: post #47

My pet theory (which is not intended to be taken too seriously) is that it is indeed a discarded light sail, and that light sail in particular was used to transport a Von Neumann probe which detached at some point after the object entered our solar system but before we first observed it. This detachment, in addition to leaving the sail tumbling, would have changed its trajectory, meaning our estimation of which direc…

...and also first arrive so soon (comparatively speaking) after the publication of The Mote in God’s Eye — an excellent novel by Larry Niven whose plot starts with the arrival of a light-sail powered tube.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#193

Post by postalrat »

person_of_color wrote: post #37
craigching wrote: post #22

Earlier quoted context omitted.

We have! https://en.m.wikipedia.org/wiki/ʻOumuamua But it’s small and moving away from us fast. We couldn’t build anything in time that could catch up to it and image it closer.

Interesting. The trajectory of O'uamuamua seems almost.. designed to scout the Sun's habitable zone. https://upload.wikimedia.org/wikipedia/commons/thumb/f/f5/Ou...

I think the theory is that it wasn't really moving relative to the sun and kinda just fell in.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#194

Post by teh_klev »

gus_massa wrote: post #137
teh_klev wrote: post #115

Earlier quoted context omitted.

> This shouldn't even be posted here. From the HN Guidelines: "anything that gratifies one's intellectual curiosity." https://news.ycombinator.com/newsguidelines.html Also don't judge a book by its title. Until you've read the book then you can't comment on whether there's a bias in play.

The same guy has published the idea of the solar sail in a paper (or preprint?). Solar sails are his research topic. The calculations that a solar sail can survive an interstellar travel are probably ok. The evidence that the solar sail is the most likely explanation is very weak.

Oh sure, and I agree maybe and many theories are likely wrong, but the point of my response was that the post is perfectly valid here on HN because it introduces discussion points such as yours...i.e. it's gratifying our intellectual curiosity (and arguments for and against) despite Loeb's interests...i.e. (sorry) solar sailed interstellar spacecraft. And this is why we're here.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#195

Post by forand »

codeflo wrote: post #189
lmilcin wrote: post #187

Earlier quoted context omitted.

Big disadvantage of Mercury is its depth in Sun's gravitational well. This is worse than planetary escape velocity, because you have to pay it on both ways (to get to Mercury as well as get back). Another problem is radiation which this close to Sun and with no atmosphere is pretty huge issue. Light intensity is irrelevant. Energy in the form of light is pretty much free within solar system unless it is somehow obstr…

Can you explain why you have to pay for the Sun's gravitational well on the way to Mercury? From the famous XKCD illustration[1] I get the impression that it might be hard to "stop at" Mercury since the pull of the Sun is relatively strong. Is there no clever trajectory that comes close enough to Mercury to get caught in its orbit? [1] https://xkcd.com/681/

You want to stop when you get to Mercury. In the XKCD illustration you have fallen quite a bit from Earth to Mercury and now have that as kinetic energy. You can dissipate that by hitting Mercury but that would likely have significant negative side effects.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#196

Post by scotth »

s1artibartfast wrote: post #120
kentonv wrote: post #110

Earlier quoted context omitted.

The existence of other planets doesn't seem to explain why they wouldn't colonize Earth. I would expect them to go everywhere.

What would the point of going everywhere be?

Maximize resource collection and manufacturing? Surely there's usefulness in raw materials.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#197

Post by TheBorogoves »

StantheBrain wrote: post #146
tgflynn wrote: post #138

Earlier quoted context omitted.

Speculating about the motives of a species that may or may not be biologically similar to us and which, even if they are similar, may well be millions of years more advanced than us is very hazardous. I think these kinds of speculations lead many people to hold all sorts of strongly held but unfounded beliefs about what ET's may or may not do here. Maybe after another million years of development a species' main moti…

Exactly, the classic Terran (of the norm), functions mainly with the help of cognitive biases and other syndromes preventing him, by social cohesion, to admit other tunnels of reality than those that composed their groups (majority currently) It's a pity, with a brain so powerful, if you knew what you could understand, admitting to omit the permanent self-awareness. Exactement, le terrien classique (de la norme), fon…

If this is a quote, how can I read the rest?

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#198

Post by hinkley »

kentonv wrote: post #55
jameshart wrote: post #49

Earlier quoted context omitted.

Which forces the logical conclusion that this isn't the first such probe, obviously.

That could only be true if they are intentionally hiding from us, rather than replicating and harvesting the solar system as fast as they can. But personally I have a hard time believing that hyper-intelligent devices would care about avoiding detection by lowly biological organisms like us.

Someone asked this once and now I can't stop thinking about it:

There's so much good stuff out in the Oort cloud, why would you ever bother climbing down the gravity well, let alone attacking the poor primitives most of the way down it?

A more likely "War of the worlds" scenario would be someone mining the outer solar system to bits and leaving without us being able to throw so much as a rock at them. If they take enough, even our ability to hunt them down for revenge would be significantly hampered.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#199

Post by hinkley »

ekianjo wrote: post #180
booleandilemma wrote: post #157

Earlier quoted context omitted.

Would a species that has mastered intergalactic travel really have anything to learn from us? I think they would either kill us, eat us, enslave us, or maybe all of the above.

you forgot another real option, "ignore us", just like we ignore ants when we walk around.

Or "blow up our sun before we can get uppity" - 3 Body Problem.

Re: Mystery of interstellar visitor 'Oumuamua gets trickier

#200

Post by senectus1 »

coredog64 wrote: post #148
kentonv wrote: post #106

Earlier quoted context omitted.

While it's entirely possible they'd have a good reason to be stealthy, I don't think it's likely to be anything we've thought of. The Prime Directive is a mushy human emotional idea, not something that makes any logical sense for a space-faring civilization to follow. If there's any competition out there among space-faring civilizations, none of them are going to tie their hands behind their backs by refusing to touc…

What resources does Earth have that wouldn’t be more plentiful elsewhere? Minerals are cheaper to extract from asteroids (no gravity well). If I have the ability to cross interstellar space, then I can’t imagine that water is even worth that much.

Sweet sweet human flesh...
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