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G933 Giveaway     Discussion Thread
Fermi Paradox... why? by Henrietta Levitt - Thu, 22 May 2014 00:54:34 EST ID:ILYTISHs No.53812 Ignore Report Reply Quick Reply
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Another thread made me start thinking about this. The Fermi Paradox states (thanks, Wikipedia):

>The Sun is a young star. There are billions of stars in the galaxy that are billions of years older;
>Some of these stars probably have Earth-like planets which, if the Earth is typical, may develop intelligent life;
>Presumably, some of these civilizations will develop interstellar travel, a technology Earth is investigating even now, such as that used in the proposed 100 Year Starship;
>At any practical pace of interstellar travel, the galaxy can be completely colonized in a few tens of millions of years.

If that's the case, why haven't we been colonized already, or at least seen evidence of intelligent life somewhere in our galaxy?

My take: either A) Life takes a long time to develop, and somehow, improbably, we're the first planet to develop an intelligent civilization in our galaxy, or at least one of the first. We don't see anyone else because there isn't anyone else to see... yet, or we're all still too far apart.

Or b) Given the size and composition constraints of a planet able to foster and sustain life (as far as we know, "habitable zone," big enough to have an atmosphere, small enough to still be rocky, etc.) and continue long enough for said life to begin to explore the galaxy, the home planet simply runs out of resources before meaningful headway can be made. I think this is more of a slow-death kind of thing where maybe we get to do some exploration within the solar system and maybe a bit beyond for a while, but overpopulation, war, disease, famine, and whatever else causes us to realign our priorities from space exploration to merely sustaining life on our own planet. A civilization that had the foresight to know something like that was happening could theoretically, if they had the goal of galactic expansion from the start, avoid this situation, but the problem is that NO civilization has that kind of 10,000 year plan from the get-go, and they all sputter out right before they could have pulled it off. There's not a textbook on "how to succeed as a species" that gets handed out to a life form when it develops self-awareness,…
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Caroline Herschel - Mon, 03 Dec 2018 13:08:50 EST ID:unNII3om No.57521 Ignore Report Quick Reply
>>57518

There has to be some kind of energy dumping to maintain such structures, and that energy would be similar to the output of the star; a completely closed system is physically impossible because the entire thing would overheat quickly.

Of course there could be exotic solutions to that problem but that would require too much speculation on our part I think. Dyson spheres themselves are still just within the realm of fantasy.
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Johannes Kepler - Mon, 03 Dec 2018 20:40:33 EST ID:457vC2+I No.57522 Ignore Report Quick Reply
>>57521
Yeah, but a Dyson sphere dumping thermal radiation would pretty much look exactly like a brown dwarf to us. Besides, if they are capturing the thermal energy, they could put it to work to cool the station, or convert excess heat energy into mass to grow the sphere.

But, no argument here, Dyson spheres are so fantastical as to skirt even the edge of science fiction, let alone fact.
>>
Paul Goldsmith - Fri, 07 Dec 2018 13:51:08 EST ID:eygzYfFg No.57531 Ignore Report Quick Reply
What about those hypothetical structures around black holes using gravitational energy from the black hole as "infinite free real estate lunch energy"? You can pretty much survive up until the fucking heat-death of the universe.
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Cecelia Payne-Gaposchkin - Sat, 08 Dec 2018 06:22:42 EST ID:L+XYIf0L No.57534 Ignore Report Quick Reply
>>57522
Pretty much. If it doesn't give off energy in the infrared, then it would probably have to be bright as fuck in the visible spectrum. Otherwise, it would have to diffuse all that captured energy somewhere
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Johan Galle - Sat, 08 Dec 2018 14:19:31 EST ID:unNII3om No.57535 Ignore Report Quick Reply
>>57522

The dyson sphere would look like a very weird brown dwarf. If a main sequence star has been encapsulated, it would still be much bigger and output more energy than any natural brownie. I don't think we've come across any stars like that, and I'm pretty sure such a discovery would throw our scientists off. Then again we're not looking for one either, so who knows?

And yeah, as I said exotic technology would have the power to hide something like this, like as you say energy to matter conversion. That's speculation, but eh who knows what is hiding right under our noses?


Sagittarius Dwarf Galaxy: Home? by Arthur Eddington - Fri, 19 Oct 2018 18:25:45 EST ID:457vC2+I No.57470 Ignore Report Reply Quick Reply
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>>original article
http://viewzone.com/milkyway.html
>>rebuttal
http://blogs.discovermagazine.com/badastronomy/2007/06/27/is-the-sun-from-another-galaxy/#.W8pUPmhKiUk

Quick rundown of the findings, which are earth-shattering if fully true, and still quite interesting if only partially true: our galaxy is orbited by a smaller spheroidal dwarf galaxy currently visible within the constellation Sagittarius. For hundreds of millions of years, it has been orbiting in a perpendicular orbit after having been pulled into the Milky Way's gravity, having stars pulled off of it each time it passes through the galactic disk, to the point now where it is very small, faint, and nearly at the point of losing gravitational cohesion. You can see a visualization of the stream of radiation left by the galaxy astronomers used to determine its path in the pic.

Now this is where it gets interesting.

It just so happens that Sol is directly within this stream of debris. For 99.9% of our orbit around the galaxy, we wouldn't be within that stream. Also, incidentally, we are at an angle to the plane of the galaxy, which was always thought a little bit odd, since most stars planetary orbital plane is parallel to the galactic plane since during accretion their accretion disks are subject to inertial forces from the star's orbit around the galaxy.

Given the extreme odds of us just happening to be within that stream, it would seem to suggest that Sol itself is native to the dwarf, having been pulled out on the dwarf's last passage through the galactic plane.

Implications:
-The period of the dwarf's orbit is around 200 million years. It is roughly 25% of the way through its orbit counting from our position in the galactic plane, which means we would have been caught by the Milky Way about 50 million years ago. The last time we passed through the plane before that, presumably still gravitationally bound to the dwarf, would have been 150 million years ago.
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Gerard Kuiper - Tue, 20 Nov 2018 19:57:37 EST ID:unNII3om No.57503 Ignore Report Quick Reply
>>57502

Point is that most of us are not real astronomers with decades in the field, we're not really qualified to make judgement on whether these arguments are sound or not. Without someone of authority in the field backing the claim up, it's better to view it with suspicion. There's enough myths out there masquerading as science.

I'm not rejecting the idea, as I've said above and earlier in this thread I like it. However this isn't science and should be treated as such, until we hear more about this from the scientific community.
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Vesto Slipher - Wed, 28 Nov 2018 23:46:17 EST ID:Z2zWh4PB No.57509 Ignore Report Quick Reply
My sign is sagittarius. Isthisrealife?
>>
Hannes Alven - Thu, 29 Nov 2018 17:30:43 EST ID:rNBxnMOH No.57510 Ignore Report Quick Reply
>>57502
> but it is intellectually dishonest to dismiss a claim merely because of who makes it.
No, it is intellectually dishonest to entertain an idea regardless of where it came from or who said it out of a misguided sense of "everyone is entitled to their own opinion=all opinions are equal". The fact that this is the only place I could find entertaining the idea means I'm wasting my time.

Suppose I were to tell you my theory on bigfoot being in fact an Indo-Aryan ancestor for all humans that crossed the land bridge into Nebraska. I can then assert said big foot has ancient magics and can trick people into thinking he is the mothman, and that his people built Atlantis but were hunted to near extinction. Why the fuck should my opinion blathered on an anonymous imageboard be taken with the same credulity as an anthropologist?

>Otherwise, you look like dogmatists.
Your intellect is way weaker than you think, if you cannot discern between this and "dogmatism". Like I said I could not find one source for the idea outside of a shitty clickbait site that sincerely talks about Mothman and Bigfoot.

>These facts require some natural explanation.
My field is more about knowing how to string together facts and implausibilities to make them sound factual--in other words how to be a propagandist or fiction writer. Any disparate collection of facts does not back up the premise the way you seem to think it does. From just what I read here it sounds as though a great many of the "facts" brought up in the viewzone blogpost are in fact disputed and not factual.

>1.) The Sagittarius Dwarf Galaxy is real.
And? The Andromeda galaxy is also on a collision course with us. These facts do not prove the premise. Look it's a neat idea but I honestly think this plays more to peoples emotions of "gee aren't we special" and general anthropocentrism. It would be a pretty funny way to explain the mass extinction patterns, if the (somewhat debunked?) trend of 25-27 million years actually fit into this time frame of his, which it doesn't. If you look at how he's trying to match it up with the evolution of life on earth you'll notice the time fram…
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Charles Bolton - Thu, 29 Nov 2018 22:04:36 EST ID:457vC2+I No.57513 Ignore Report Quick Reply
>>57510
Ad hominem and relativistic realism may both be fallacies to you, but that doesn't make them logically equivalent. When you are claiming one thing is something else it obviously is not, it makes me suspicious, when I assume if you can tell this is bunk you should have very well developed internal ideas on why. Why not reference them instead?

I don't really have a problem with you rejecting this idea, but with arriving at what may be a sound conclusion by erroneous means, and then insisting that these are the *primary* reasons to reject the idea. The next time it might not be so cut and dry and such sloppiness might get you into a lot of trouble, and if you teach people that is the appropriate way to react, then the error gradually becomes permanent.
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Grote Reuber - Fri, 07 Dec 2018 19:24:33 EST ID:D7Nw/FlX No.57533 Ignore Report Quick Reply
Personally, I'm more worried about Yellowstone.


No flat earth thread? by Jessica Tandy needs candy !!vVWR8L52 - Mon, 29 Oct 2018 19:21:02 EST ID:F2wgR3l2 No.57479 Ignore Report Reply Quick Reply
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And before you ask /tinfoil/ is currently in the middle of forum sliding and if this it's treated as a serious topic then that's like saying climate to deniers are right

https://m.youtube.com/watch?v=e5ACN9iF8Jw
https://m.youtube.com/watch?v=qkRnJutL5ko
https://m.youtube.com/watch?v=CGjFAe018oA

I have included counter arguments so that people can reach their own conclusions, it's hard to go against the grain and try to prove a point therefore

>It certainly is interesting to see the shift of focus in space programs from official government organisations to privately-run organisations. Whether or not that's a good thing will, of course, vary with your political views, but the ultimate outcome isn't much different. After all, corporations are driven by profit, not the pursuit of knowledge or truth.
>What is surprising, however, is the new generation of people shouting "It's true, I saw it on TV!" Except this time, it's the Internet. We have already witnessed the shortfalls of this blind belief in online materials; just consider recent US elections, the political Facebook campaigns in the UK, or the many fake-news sites run from countries like Macedonia.

In the days of Newton and Hailey there weren't dogmatic schools that tried to systemize learning. People were free to experiment and come up with theories, look at Faraday, the father of electricity. He was smart even though he didn't have a degree.

Basically universities are what the Catholic Church was back then (let's grow up no alter boy jokes please) in that they are dogmatic and have a reason to protect their source of money and funding.

I mean why was the Bush administration so keen on going to mars?
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Bernhard Schmidt - Thu, 15 Nov 2018 20:22:07 EST ID:rNBxnMOH No.57495 Ignore Report Quick Reply
>>57481
I still don't even think there are real flat earthers. I am 85.6% positive that this, like reptilians and 9/11 not happening due to holograms, is either a joke that got taken seriously by a couple idiots, or a large government disinfo campaign. If some idiot is actually blanketing tinfoil threads calling people shills for not believing in the dumbest bs while sliding more reasonable threads then odds are the purpose is to discredit potential leakers and whistleblowers and to utterly destroy their sites until nobody takes them seriously and nobody goes there anymore.

As for this thread itself it should be locked and deleted because this isn't even /tinfoil/ material this is just stupid nb
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Henry Russell - Wed, 28 Nov 2018 01:30:51 EST ID:kysB+hps No.57508 Ignore Report Quick Reply
>>57479
the moon is a lie!
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Bernhard Schmidt - Fri, 30 Nov 2018 00:41:13 EST ID:sgaYzgip No.57514 Ignore Report Quick Reply
>>57479
Space isn't real retard, it's cgi magic.
Fucking illuminati
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Michael - Thu, 06 Dec 2018 23:38:20 EST ID:Q1CtxL06 No.57530 Ignore Report Quick Reply
>>57514
apostrophes are an Illuminati conspiracy, get woke fool
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Georges-Henri Lemaitre - Fri, 07 Dec 2018 16:17:18 EST ID:fA4CdeQA No.57532 Ignore Report Quick Reply
>>57508

TRUTH! Have you ever seen the moon except in pictures? That's because it's all edited in by nasa. Aliens implanted false memories of seeing the moon. It's all a big conspiracy to keep the human race ignorant and in line.


Building Blocks of Life Found on Mars by Otto Struve - Thu, 07 Jun 2018 19:12:35 EST ID:eygzYfFg No.57290 Ignore Report Reply Quick Reply
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https://news.nationalgeographic.com/2018/06/mars-organic-compounds-methane-curiosity-space-science/

>Two landmark discoveries reveal organic carbon on the red planet, shaping the future hunt for life on Mars.

I'm scared guys. This could mean life is common in the universe, which means the Great Filter is ahead of us instead of behind us.

😰😰😰😰😰

Then again, maybe this can show us the Great Filter is already behind us but when it comes to cosmic horror, I'm a half-empty kinda guy.
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Vesto Slipher - Tue, 04 Dec 2018 04:59:58 EST ID:BTs3t51f No.57524 Ignore Report Quick Reply
>>57290
Apparently Titan has methane too
>The carbon in methane molecules comes in different varieties, or isotopes � carbon-12 (12C) and carbon-13 (13C). Each 13C atom has an extra neutron in its nucleus, making them slightly heavier than 12C atoms, so the GCMS can distinguish between methane with 12C and methane with 13C.

>Living organisms have a preference for carbon-12. As a result, carbon-containing molecules, such as methane, that are associated with life on Earth get enriched in 12C. The ratio of 12C to 13C is a marker or signature of life.� However, the team did not see 12C enrichment in the methane on Titan.


>>57494
>The real reason we are probably unlikely to encounter intelligent life is because odds are the development of a technology producing race is followed immediately by largescale extinction if not outright planetary sterilization in some cases.
In my opinion largescale extinction may be avoided with neurological/psychological/social variables. Language, social psychology, shared information is what allowed us to progress into the next stage of society. For a small tribe it may be beneficial for you to believe what others believe without questioning it, in modern day society that is a trait that is very easily taken advantage of. I believe that with natural selection, it may be possible for some society in the future to avoid extinction. As far as we know we are the first societies to make it this far. With the deaths of many societies, maybe there will be a future race of people more suitable for progression with the necessary neurological/social conditions.

Sure, avoiding large scale extinction is possible, but is it likely? Humans have a destructive need to feel comfortable, this should be true with every organism that makes it this far. A race of people with no greed, who ascend past their animalistic instincts and desires, who prioritize their long term future and health for short term prosperity is possible, but how likely is it that a race like this is formed before mass extinction? It could very well be 1e-∞%
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Johannes Kepler - Tue, 04 Dec 2018 18:39:07 EST ID:457vC2+I No.57525 Ignore Report Quick Reply
>>57524
Titan's methane and organics are compounded from benzene in the upper atmosphere by cosmic rays, though. If Titan has life, that's not evidence of it. There was actually an infographic on /spooky/ yesterday for some reason showing the chemical processes which lead to organic compound formation in Titan's atmosphere, but I can't be assed to go find it.

>> but how likely is it that a race like this is formed before mass extinction?
But, space is infinite in extent. So even if the factor for species to develop self-sustaining attitudes is 1e-∞% (which I sincerely doubt) it still should occur an endless number of times in the universe.

I don't think we really could assign a numerical value to such a probability, because there are too many unknowns. Sapient beings are dynamical systems that don't evolve predictably. One idea that one of them has can change the course of the history of their whole species forever, for better or worse. There's no way to account for that mathematically, other than to say that the potential of sapient life is infinitely unknown.
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Viktor Ambartsumian - Thu, 06 Dec 2018 07:05:35 EST ID:BTs3t51f No.57527 Ignore Report Quick Reply
>>57525
In my post I quoted
>>Living organisms have a preference for carbon-12. As a result, carbon-containing molecules, such as methane, that are associated with life on Earth get enriched in 12C. The ratio of 12C to 13C is a marker or signature of life.� However, the team did not see 12C enrichment in the methane on Titan.
Because I don't believe there to be life on mars or titan
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Paul Goldsmith - Thu, 06 Dec 2018 18:42:25 EST ID:457vC2+I No.57528 Ignore Report Quick Reply
>>57527
Well, how could I know that's why you quoted it? You didn't make a comment about it, and its just a fact. But if you just change my post from saying, 'by cosmic rays, though', but to 'by cosmic rays, as you imply' then it comes out the same.

To be clear, however, just because organics in Titan's atmosphere aren't biological in origin, doesn't mean Titan itself doesn't support life, it just doesn't mean that it does support life. It could have subterranean earth-like biota, or support life that operates on a different biochemistry. We just don't know until we go there.

But, Europa is probably a better candidate moon to find earth-like life, for sure.
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Galileo Galilei - Thu, 06 Dec 2018 18:46:48 EST ID:rNBxnMOH No.57529 Ignore Report Quick Reply
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>>57524
I wasn't talking about human societies. I was talking about alien societies. I explicitly meant that there is a high chance humanity wipes itself out as within a very tiny period of time we went from industrialization to almost killing a lot of the biosphere with nuclear weapons--which we still might do in the next century--as well as things like climate change. What if we created a runaway greenhouse effect? Maybe not totally Venus tier, but something like it? We have already proven of ourselves within a single generation that the jump to that kind of pre-space industrial advancement could easily kill us all. It is not inconceivable that a majority of races in the universe that did make that jump to industrialization types of societies promptly ended up killing themselves and most of the planet, just as much as it is conceivable that on many planets a type of life similar to bacteria arising promptly (in geological terms) farted out enough oxygen into the atmosphere to kill almost everyone microbial thus creating a near-human breathable atmosphere.

What I am stating is that man is a bacteria I want to see infecting other worlds but the problem is that it is quite proven how hazardous it is to make that jump towards being a more advanced technological society without dooming themselves somehow. Not to mention as I stated previously that humanity as anything but a vaguely enlightened tribe of apes has only existed for tens of thousands of years, and that the accepted span for "historical" that is to say post-agricultural man has existed for only 10-17.000 years, which is absolutely nothing in geological terms of the hundreds of millions of years of life on earth.

Ergo, you are not just plotting the spatial but also the temporal coordinates to a planet in which a) life has arisen, b) life is at the stage of abstract thinking, c) life has achieved technical progress and advancement without having killed itself in the process. While the universe and even our local stellar cluster may be vast, that is actually an incredibly small set of coordinates.

It would of course be much, much easier if you could somehow greatly expand either your spatial or temporal search.


How did such an inconceivably awesome object get stuck with such a stupid name? by Henrietta Levitt - Thu, 18 Oct 2018 20:49:56 EST ID:gVSzJCUs No.57466 Ignore Report Reply Quick Reply
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"Milky Way" sounds so weak and lame for a galaxy, especially the one we're renting. Cant we have come up with a cooler handle for our cosmic digs?
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Alan Guth - Sat, 01 Dec 2018 14:00:34 EST ID:L+ln+qD9 No.57516 Ignore Report Quick Reply
>>57473
>>57515
Now this fired up my neurons, how do you actually see the stars? How do you exactly get rid of light pollution, for an example, if I somehow shut down the city power grid and the weather is perfectly clear, will I be able to instantly see the stars or they're gradually start to be seen? I know there are a lot of factors but this is just toned down and hypothetical.
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Karl Jansky - Sun, 02 Dec 2018 18:47:40 EST ID:457vC2+I No.57519 Ignore Report Quick Reply
>>57516
If you shut down the power grid, the sky would darken instantly, because moving at the speed of light even the ambient photons would leave before you had time to notice a dimming. But, it would seem to take a few seconds, because your eyes would have to adjust.
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Christiaan Huygens - Mon, 03 Dec 2018 11:34:34 EST ID:gRsMKZUR No.57520 Ignore Report Quick Reply
>>57516
there are dark zones around. probably some near where you live. or get a look at the sky on a nighttime flight, it's pretty awesome above most of the atmosphere
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Johannes Kepler - Mon, 03 Dec 2018 20:45:06 EST ID:457vC2+I No.57523 Ignore Report Quick Reply
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>>57520
Stars, y'say? Heard there's a mighty fine mess of 'em iffen ya know whar to look. Use this here map and prospect yerself a dark zone, pardners:
https://darksitefinder.com/maps/world.html#4/36.39/22.15
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Riccardo Giacconi - Wed, 05 Dec 2018 10:01:26 EST ID:IpCFcmN3 No.57526 Ignore Report Quick Reply
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>>57519
that kind of a technical answer i needed, thanks. sorry for being a clueless plebian.


Mars eclipse by William Huggins - Sun, 25 Nov 2018 21:39:22 EST ID:ckw062Hz No.57504 Ignore Report Reply Quick Reply
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if one or 2 of mars moons came between mars and earth during a time where mars is clearest and easiest to see with the naked eye, could one tell the moons were dimming mars red orange light? I understand phobos is really close but could the other moon make a significant enough eclipse or dimming effect to the red dot we see from earth
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Fred Hoyle - Mon, 26 Nov 2018 17:36:55 EST ID:457vC2+I No.57505 Ignore Report Quick Reply
Naw, not with the naked eye. Phobos, the larger moon, is only 27 km across.


Perseid meteor shower! by Johann Encke - Wed, 31 Jul 2013 11:29:34 EST ID:evrPe8Vs No.51233 Ignore Report Reply Quick Reply
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AWWWW YEAAAH.
Anyone else gonna observe this beautiful event?


Incase you haven't heard from AUG 12th to the 13th between 10:30PM and 4:30 AM, The sky's gonna light up with massive fireballs brighter than Jupiter.
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William Lassell - Sat, 19 Aug 2017 22:02:46 EST ID:dG4sHLwu No.57004 Ignore Report Quick Reply
I caught sight of seven or so. Too bad it was too cloudy most of the time. Really want to go out of the city for next year.
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William Huggins - Fri, 10 Aug 2018 21:16:36 EST ID:ncMk3uyQ No.57421 Ignore Report Quick Reply
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Anyone going to observe this year's Perseid meteor shower?

Hoping for a cloudless sky.
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Christiaan Huygens - Sun, 19 Aug 2018 18:20:31 EST ID:457vC2+I No.57435 Ignore Report Quick Reply
>>57000
Almost all meteor showers are annual or cyclical, dood. We aren't here to teach you astronomy, we're here to talk about it.
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Roger Penrose - Tue, 09 Oct 2018 05:59:14 EST ID:U4u72hWB No.57464 Ignore Report Quick Reply
>>57000
if you don't ask they don't have time to tell.
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Wilhelm Beer - Thu, 15 Nov 2018 04:28:30 EST ID:N7xCPuZj No.57491 Ignore Report Quick Reply
Leonid shower's s'pposed to be coming up this weekend, for those who won't have a big honkin' snowstorm gumming up the skies, at least.


/STEM/ by Arthur Eddington - Thu, 01 Nov 2018 23:18:58 EST ID:7ez/W0kB No.57485 Ignore Report Reply Quick Reply
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Slow board, maybe we should have /stem/
>>>/420/247062
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Subramanyan Chandrasekhar - Fri, 02 Nov 2018 03:15:02 EST ID:m8u2eXUq No.57486 Ignore Report Quick Reply
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>>57485
Everyone is planning a space party lately



Maybe they need more time to planet.


duuuuuude by Galileo Galilei - Thu, 01 Nov 2018 22:59:06 EST ID:6fcUdTGI No.57484 Ignore Report Reply Quick Reply
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https://www.eso.org/public/news/eso1835/
see that spherical black shit under the gas? that the event horizon. not actually a thing but a region where even light falls in. that bubble isn't even contorned by gas but the gas's glow stretches in a sphere because of gravity tides.
this shit is awesome that's what it is


Dark Matter and GR - struggling to understand by Bart Bok - Sun, 30 Sep 2018 09:15:14 EST ID:9RKOIT3O No.57458 Ignore Report Reply Quick Reply
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Hey there fellow egghead stoners. Would you be able to guide me through this?

So, the whole concept of dark matter and energy. I find it a little dubious, I take it this hasn't been confirmed in any way - rather, like many theories in physics has been introduced as an attempted explanation of mismatch between empirical data and theoretical predictions.

But this is just an impression I've got from the superficial knowledge of modern physics I've got, so I'd rather first understand the basis for this hypothesis better before judging it dubious.

So the way I understand it is the concept was proposed in 30s to explain the observed movement of galaxies, in particular why some stay in clusters rather than be launched off due to the acquired speed.

So it is inferred that there must be enough gravity force to keep them together instead. This begs the first question: what is the expected mass calculation based on? As in, how'd they go about measuring that?

But all right, aside from that bit I'm missing, assume the mass predictions are sound. In Newtonian mechanics - so far so good. But now if we introduce GR we allow the concept of black holes which would escape our observations. Why does that not account for 'dark matter' effect? It fits the criteria of (1) great mass (2) inability to be observed

So the way this is taken into account, I understand, that all right - there may be black holes which we cannot observe, but we still have a rough prediction on their mass which we infer from gravitational lensing - and that is way not enough to account for 'dark matter', and hence the concept remains valid.

My questions to you anons:
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Johann Encke - Mon, 01 Oct 2018 01:21:26 EST ID:457vC2+I No.57461 Ignore Report Quick Reply
>> what is the expected mass calculation based on?
Light from main sequence stars. We look at a galaxy, look at it's luminosity to estimate the number of main sequence stars, and estimate mass from that. Almost all galaxies thus have a totally insufficient amount of normal matter to account for their mass (although we have found some galaxies without dark matter, or with hardly anything but dark matter, but this is quite rare) or rather, what their mass would have to be in order for them to maintain coherency.

>> there may be black holes which we cannot observe, but we still have a rough prediction on their mass which we infer from gravitational lensing
You would think we could do this, but in practice we can only use gravitational lensing and other gravitational effects to detect black holes in this way if there is a significant amount of parallax on the black hole (otherwise, unless we are just lucky enough to have a sufficiently bright star in line with it and us along its event horizon, we will simply miss it) for this reason we can use this method to kind of hunt randomly for black holes, we can't use it to estimate how many black holes there actually are -- we have no idea as to the answer to that question, from an empirical standpoint.
>>2) Any resources on the subject to recommend which would explain in bit more detail how the calculations made?
https://ned.ipac.caltech.edu/level5/March05/Read/Read1.html
>>iii) therefore there must be mass
I think there are strong reasons to suspect this line of thinking might be flawed, especially since the only reason we describe dark matter as matter is simply because we can't think of anything else to describe it as. Relatively popular but unaccepted are theories that dark matter and energy represent the influence of alternate quantum realities upon our universe, or may otherwise be some sort of shadow of the m-brane. Unfortunately, a long running contender for non-DM/DE explanations, MOND, was recently disqualified due to new observations, although people are seeing if it can be saved with an update.

In short, absolutely it could be something else. DM/DE really is just a placeholder. But that begs the question: what…
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Fred Hoyle - Sat, 06 Oct 2018 19:23:55 EST ID:8/fKg+Ea No.57462 Ignore Report Quick Reply
>>57461

Hopefully the James Webb space telescope will be launching under it's most recent date in 2021 and provide us some new insights.


That FTL means time travel meme by Pierre-Simon Laplace - Sat, 16 Dec 2017 22:22:45 EST ID:hGyQlc1t No.57130 Ignore Report Reply Quick Reply
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I have a question regarding this:
If you look at this gif it shows you "backwards" travel:
The first "jump" after the first acceleration points into the direction that corresponds to the lower left quadrant of the previous reference frame leading to backwards time travel.
However: Drawing it into the upper right quadrant should be equally legal which would imply forward time travel. This would imply that direction you are moving in space would dictate the direction of the "time travel" which seems entirely non-sensical to me.
I guess this is also the point but I still get the feeling I'm missing something here.
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Russel Hulse - Thu, 27 Sep 2018 17:46:18 EST ID:unNII3om No.57454 Ignore Report Quick Reply
>>57451

>'You' could make it if 'you' are defined as the singular positions and velocity of your molecules at a given point in time.

Which is not what I view as 'you'. We do agree on that consciousness is something else than the matter that give rise to it, but I think we have different perspectives on what truly is 'you'. And I don't think we should ignore the super-structured of matter, neural nets, which is the reason why personality and memories are so long lived.

I am well aware of the Ship of Theseus as a philosphical paradox, so let me clarify my position.
I see consciousness as primarily a process of interactions happening in time, in the form of interactions between structures of matter. It is a matter of causality, not the constituent atoms. As long as the super-structures and processes of those structures remains intact, 'you' are alive. The matter making up your brain can be constantly replaced, as long as the process itself is unbroken the fact that the wood of your ship today is not the wood when your ship was made does not matter.


Now perhaps I misunderstand quantum teleportation, and if I do please tell me. But as I see it, once that process is broken for even a planck-length of time, you're no more.
The information of you is transmitted, but the process that is you is obliterated.
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Harlow Shapley - Thu, 27 Sep 2018 18:20:40 EST ID:457vC2+I No.57455 Ignore Report Quick Reply
>>57454
>> But as I see it, once that process is broken for even a planck-length of time, you're no more.
The idea would be that it would occur simultaneously, with no break in operation.
Consider it this way -- people have been resuscitated from an utterly dead state, because their bodies were so cold that molecular motion slowed down so significantly that no advanced brain deterioration could occur. We assume that the person reanimated was the same person, and not some sort of psychic clone; because why would it be?
So if, prior to teleportation, your global body temperature reached absolute zero and stayed that way, it wouldn't matter if teleportation took a second or a thousand years, as long as every molecule was kept at absolute zero (ignoring the problem of ice crystal formation for now -- lets assume we're talking about a sentient robot, or perhaps a tardigrade like lifeform.)

>> as long as the process itself is unbroken
But that was the point of my previous post. I attempted to illustrate how the process that generates your consciousness has nothing to do with the particular atoms and everything to do with the pattern (process) in which they are arranged. So, in our hypothetical teleporter, all structures and structural processes remain intact. There is no lapsed period of operation -- at the smallest physical scale, both in space and time, there is no difference between the start and end configuration. By the fundamental definition of 'process' from a physics standpoint, nothing could be broken.

Which means we are left with two alternatives; either what you consider to be your consciousness is indeed the result of the pattern of configuration of your brain, which means that if that pattern of configuration is replicated exactly, the same phenomena arises -- like causes leading to like results, the foundation of empiricism. Alternatively, if consciousness did not persist through this transition, we would have to speculate as to why -- the most clear implication being that there is some 'hidden variable' beyond the physical configuration that enables the persistence of consciousness. Since, from a physicists standpoint, we believe that the physi…
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Bernard-Ferdinand Lyot - Thu, 27 Sep 2018 18:55:44 EST ID:3nlPOKZc No.57456 Ignore Report Quick Reply
>>57130
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Bart Bok - Sun, 30 Sep 2018 09:42:04 EST ID:9RKOIT3O No.57459 Ignore Report Quick Reply
>>57130
>However: Drawing it into the upper right quadrant should be equally legal
Equally illegal? ;)

>This would imply that direction you are moving in space would dictate the direction of the "time travel" which seems entirely non-sensical to me.
These diagrams are entirely symmetrical in terms of all dimensions, as in choice of 'left' and 'right' just as 'up' and 'down' is arbitrary

I feel there is an ambiguity in what constitutes time travel. As in, the intuition we typically may have about this being '2018-09-30' -> '2008-09-30' same place.

But in terms of general relativity, any travel with speed >c is time travel. This is called moving in a 'timelike curve' in 4D spacetime - as opposed to 'spacelike curves' which we (and all we know) typically move on. On the GIF all curves within yellow area are spacelike and blue area timelike.

So for example if you 'teleported' a light year away from your current whereabouts, that'd be considered time travel. Because if you send a light signal to earth, and teleport back - you will not see it for another year. So you influenced the future without exactly 'changing' the date on your calendar

Mind you if you simply travel half a year back/forward keeping your position fixed, you'd arrive in some different place because likely the earth, sun and entire galaxy would've moved away.
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Bart Bok - Sun, 30 Sep 2018 09:55:02 EST ID:9RKOIT3O No.57460 Ignore Report Quick Reply
or maybe better example:
  1. you travel a year back in time from now to 2017
  2. you end up a light year away from initial position
  3. 2017 you wants to send stock market results to 2018 you
  4. at best 2017 you will be able to send them with speed of light
  5. light takes a year to arrive to 2018
  6. in that case, the information you're sending arrives in 2018 and you haven't actually managed to send it back in time, because it still has to make up for the distance before it reaches you

if you change space distance from 1 light year away to 0.5 light year away however, you will be able to send information to 'past you' (with speed of light) so it arrives mid-2017 (and either you're filthy rich or paradoxically disappear hehehe)


Interchan Warning System by Maximilian Wolf - Fri, 28 Sep 2018 00:48:46 EST ID:9ugkcJUP No.57457 Ignore Report Reply Quick Reply
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***THIS IS THE INTERCHAN WARNING SYSTEM***
THIS IS NOT A TEST
MESSAGE TO FOLLOW
MESSAGE FOLLOWS:

DO NOT SHIFT THE TIMELINE. DO NOT LISTEN TO 'AI' BASED POSTS.
DO NOT SHIFT TO TIMELINE: 5E8FD0AA-44ED-4868-B04C-9E33754CF9BC
DO NOT DESPAIR

***End of message***
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Bernhard Schmidt - Thu, 15 Nov 2018 20:29:27 EST ID:rNBxnMOH No.57496 Ignore Report Quick Reply
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All weebs should be shot nb


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