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Old 08-05-2016, 12:51 PM   #46
Urwumpe
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Default KIC 8462852 Faded Throughout the Kepler Mission

The anomalous star had been in the news some months ago because of its strange huge, irregular luminosity changes, which did not find a good natural explanation, now there is an update based on much more data.

http://arxiv.org/abs/1608.01316

Currently known natural processes still can't explain it, something completely new or unnatural has become more likely now. Looks like a very exciting research object already.

What ever it is that causes the phenomena, chances are high that is this star is significant enough to become a one of the few rare stars with a name now (Like Barnards Star).


PS: And was there really no thread about it yet? I searched for the star ID and the star catalog prefix, but found no results.
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Old 08-05-2016, 12:59 PM   #47
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 PS: And was there really no thread about it yet? I searched for the star ID and the star catalog prefix, but found no results.
There was. You even commented in it: http://www.orbiter-forum.com/showthread.php?t=36304
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Old 08-05-2016, 01:11 PM   #48
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 There was. You even commented in it: http://www.orbiter-forum.com/showthread.php?t=36304
Unbelievable - three pages of discussion and we NEVER mentioned the ID of the star.
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Old 08-05-2016, 04:02 PM   #49
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I'm still weary of even suggesting a non-natural reason for this, but this really is baffling.

EDIT: Reading through the paper the author suggests that a potential cause for the dimming could be interstellar "dust" between Sol and KIC 8462852 yet there was no dimming of 192 nearby reference stars. Another possibility is a polar spot, which seems a more likely possibility but it would have to be an extraordinarily long lasting one.

Last edited by Kyle; 08-05-2016 at 04:16 PM.
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Old 08-05-2016, 05:33 PM   #50
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 I'm still weary of even suggesting a non-natural reason for this, but this really is baffling.

EDIT: Reading through the paper the author suggests that a potential cause for the dimming could be interstellar "dust" between Sol and KIC 8462852 yet there was no dimming of 192 nearby reference stars. Another possibility is a polar spot, which seems a more likely possibility but it would have to be an extraordinarily long lasting one.
Exactly - I am all for considering the natural causes, especially since assuming unnatural causes requires unnatural evidence. But the more we learn about this star, the more the unnatural becomes the appealing exit from frustrating natural science on a star, that does not want to play by our rules.
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Old 08-06-2016, 12:44 AM   #51
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Discovery / Seeker: Kepler's 'Alien Megastructure' Star Just Got Weirder


Threads on the topic now merged with the new title adopted.
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Old 08-06-2016, 09:44 AM   #52
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 assuming unnatural causes requires unnatural evidence.
First of all, the "extraordinary claims..." adage was coined by Carl Sagan when he was presented with an extraordinary claim with pretty solid evidence. Problem was, Mr. Sagan was uncomfortable with accepting the evidenced claim, so he coined this logical fallacy to be able ignore the evidence by artificially inflating the standard of proof required for claims he did not like.

Second, the claim of alien megastructure around a remote star is not at all extraordinary, in the sense that it does not violate our current understanding of the universe: we know that abiogenesis is possible (happened at least once here), we know that it may ultimately lead to the rise of an intelligent civilization (ditto) and we know that the physical laws don't prevent creation of megastructures.

If someone comes up with a reasonable natural mechanism to explain the star's dimming then you could argue to accept this mechanism instead of aliens by Occam's razor. The key word, though, is "reasonable". Occam tells us to go with the solution requiring less assumptions, and so far "natural" explanations usually rely on some contrived combination of parameters which somehow does not happen elsewhere in the universe, while the alien megastructure only requires you to assume that civilizations can reach Kardashev's stage II (i.e. they don't always collapse).

Indeed, this may be the unexpected solution to Fermi's Paradox: it's not that aliens have never been observed, it's that each time aliens are observed, the skeptics are chanting "no extraordinary evidence!" to shout down the claim.
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Old 08-06-2016, 10:53 AM   #53
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 Indeed, this may be the unexpected solution to Fermi's Paradox: it's not that aliens have never been observed, it's that each time aliens are observed, the skeptics are chanting "no extraordinary evidence!" to shout down the claim.
Well, the problem is not just that simple. The key problem for such a alien mega structure as hypothesis is:

What are its properties?

We could sure always explain everything with "That is caused by alien technology that we don't fully understand". But then we can't falsify it - we could not say, when something must not be this alien technology.

What we would need is a way to proof it in both directions. From observations to structure. And from structure to observations. Only then, we could be sure that it really must be such a structure. Until that point, we can only say "It has properties in common with our understanding how such a megastructure would be like, but there are alternative explanations possible".

I mean... how could you proof that the bright fast moving star in the sky is the ISS? If you don't know the ISS exists and don't know its exact properties? A good enough photograph of it would sure be enough to tell it is a machine. But at which point could we get a good enough observation of it to replicate the known properties of it?
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Old 08-06-2016, 11:53 AM   #54
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 Well, the problem is not just that simple. The key problem for such a alien mega structure as hypothesis is:

What are its properties?
For starters, if someone is building a Dyson swarm, then we should see an orbiting cloud of material which gets bigger with time, as the civilization's demand for energy grows and the swarm is expanded... oh wait, that's exactly what we are seeing. Especially if the dimming has been going over the last century, as the recent reevaluation of old data shows.

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 We could sure always explain everything with "That is caused by alien technology that we don't fully understand". But then we can't falsify it - we could not say, when something must not be this alien technology.
For example, one could theorize that the alien equipment should produce waste heat and look for suitable signatures in far-IR.

Problem is, getting funding for that would require formulating a research proposal which uses alien megastructure as a working hypothesis. That makes it a non-starter, because people with your mindset are so prevalent in the academia that the proposal would be killed once the reviewer sees the word "alien", regardless of its merits.
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Old 08-06-2016, 12:23 PM   #55
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 For starters, if someone is building a Dyson swarm, then we should see an orbiting cloud of material which gets bigger with time, as the civilization's demand for energy grows and the swarm is expanded... oh wait, that's exactly what we are seeing. Especially if the dimming has been going over the last century, as the recent reevaluation of old data shows.
What should be the future trend then?

And why should it be a Dyson swarm? The primary trait of a Dyson swarm is, that it is engineered right? so, intelligent designers would not randomly place the modules of the swarm, but actually show some pattern and some kind of commissioning. The modules of the swarm have to be build somewhere, with LOTS of material and consuming LOTS of energy. Possibly the Dyson swarm would feed itself, transferring the energy where the modules are build.

This all means: You can't just take the plot and anything goes. Even for an assumed Dyson Swarm, there are constraints. And there are other observations that result of these constraints and that could be observed.

Worst of all: Can you even make a coarse prediction what orbital radius the Dyson Swarm has? This is a very important property, because it defines most of the behavior of the swarm.

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 people with your mindset
Nice of you to at least acknowledge that I have a mind.
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Old 08-06-2016, 01:36 PM   #56
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I think at this point the only way we're going to get a definitive answer to this mystery by directly imaging the objects in the system. The New Worlds Mission would probably be able to do that if/when it launches. I'd imagine if star sized alien megastructures orbiting KIC 8462852 are photographed it will be immediately obvious as something that could not be explained through a natural process (and what a discovery that would be).
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Old 08-06-2016, 02:39 PM   #57
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The fact is that alien life is not common based on what we know so far; we have yet to observe any sort of extraterrestrial life anywhere. Technology-capable life would seem to be even less common; on our own life-abundant planet there is only one such species.

As for life that can build mega-structures, we have observed zero instances of this. Yes, we can do the math and engineering on paper, but spaceflight is hard and the fact is we ourselves may never make it beyond Mars, if we even get that far. A lot of things have to fall into place before we can start building mega-structures, not the least of which is we have to develop sources of high energy and avoid destroying ourselves in the process.

So we can't rule out alien life, but it's pretty far down the assumption list. This may take may years of data gathering to come up with a good theory.

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  because people with your mindset
Way to make this a personal thing, there.
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Old 08-06-2016, 04:35 PM   #58
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 This all means: You can't just take the plot and anything goes. Even for an assumed Dyson Swarm, there are constraints. And there are other observations that result of these constraints and that could be observed.
Of course. But here's the funny thing: if the proposed theory was that it's a cloud of comets, you wouldn't be demanding a detailed orbital solution.

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 Worst of all: Can you even make a coarse prediction what orbital radius the Dyson Swarm has?
Mercury's maybe less.

---------- Post added at 05:35 PM ---------- Previous post was at 04:06 PM ----------

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  As for life that can build mega-structures, we have observed zero instances of this.
So what? We have also observed zero instances of gravity waves before the 15SEP2015 event at LIGO.

In reality, it's all about the difference between a type 1 and type 2 error:



The skeptical mindset nowadays prevalent in the scientific community is characterized by being extremely harsh on people making false positive (type 1) errors combined with extreme leniency on people making false negative (type 2) errors. For that reason, falsely announcing the detection of aliens (type 1) will land you in trouble, while ignoring an actual alien (type 2) has no negative consequences.

The "extraordinary claims..." adage follows this mindset. As there is a negative (social and professional) consequence of making a type 1 error, the wisdom is that we should artificially increase the standard of evidence of required for "extraordinary" claims, so we avoid making a type 1 error. Now the weakness here is that by doing so we increase risk of making a type 2 error, but that's okay, because a type 2 error has no negative consequences for the scientist.

Say, for example, that I have an objective proof of alien megastructure at 95% confidence. This means that there is an objective 5% chance that there is no alien megastructure. So if I publish, I have 5% risk of trashing my career, but if I don't, I have no risk... So there is no reason for me to publish it. This is why I have said earlier that we may have had earlier observations of astroengineering, but people are sitting on them out of fear of ridicule.

Naomi Oreskes argues that different treatment of type 1 and 2 errors is detrimental, because it leads to suppression of research results in situations where the cost of type 1 error is lower than that of a type 2 error:

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Is a Type 1 error worse than a Type 2? It depends on your point of view, and on the risks inherent in getting the answer wrong. The fear of the Type 1 error asks us to play dumb; in effect, to start from scratch and act as if we know nothing. That makes sense when we really donít know whatís going on, as in the early stages of a scientific investigation. It also makes sense in a court of law, where we presume innocence to protect ourselves from government tyranny and overzealous prosecutors ó but there are no doubt prosecutors who would argue for a lower standard to protect society from crime.

When applied to evaluating environmental hazards, the fear of gullibility can lead us to understate threats. It places the burden of proof on the victim rather than, for example, on the manufacturer of a harmful product. The consequence is that we may fail to protect people who are really getting hurt.

And what if we arenít dumb? What if we have evidence to support a cause-and-effect relationship? Letís say you know how a particular chemical is harmful; for example, that it has been shown to interfere with cell function in laboratory mice. Then it might be reasonable to accept a lower statistical threshold when examining effects in people, because you already have reason to believe that the observed effect is not just chance.

This is what the United States government argued in the case of secondhand smoke. Since bystanders inhaled the same chemicals as smokers, and those chemicals were known to be carcinogenic, it stood to reason that secondhand smoke would be carcinogenic, too. That is why the Environmental Protection Agency accepted a (slightly) lower burden of proof: 90 percent instead of 95 percent.
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Old 08-06-2016, 04:58 PM   #59
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 Of course. But here's the funny thing: if the proposed theory was that it's a cloud of comets, you wouldn't be demanding a detailed orbital solution.
Actually wrong - I would still demand it to explain this anomaly. After all - without knowing the orbital elements, how could we explain this NEW anomaly? How can such a cloud of comets exist in such a density? An exotic cloud of comets is a possible explanation then for the observation but we have still no evidence that such a cloud really exists.

Or if it would be the star from time to time emitting strange mass ejections that reduce its thermal signature and its type F category being actually wrong - it would require still supporting evidence.
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Old 08-06-2016, 06:11 PM   #60
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If it's comets I'd certainly like to know how a seemingly average-aged F3V sequence star is such a mess of a solar system. Normally one would expect to see something like that in a young system like Vega and Fomalhault, for example.
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