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Tabby's star is dimming at an incredible rate

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Re: Tabby's star is dimming at an incredible rate

#61

Post by wbl »

ethanbond wrote: post #45
m_mueller wrote: post #43

Earlier quoted context omitted.

Stellar ones have a soft upper boundary. If they are so old and massive that they become planetary or even stellar sized - well the'd start drawing stealing a good chunk of the host galaxy and form their own one - with blackjack and hookers. I.e. a flickering star would be the least of your worries ;-).

What causes the soft upper boundary?

The mass of the star before it went and formed a black hole. The bigger a star, the hotter it is, and the more evaporates from the surface, and the shorter it lives. Large blackholes grow through things falling into them.

Re: Tabby's star is dimming at an incredible rate

#62

Post by CamperBob2 »

singularity2001 wrote: post #48

Sunspots, debris and/or a distant cloud are not completely ruled out: https://arxiv.org/abs/1608.01316 Wiki: The leading hypothesis, based on a lack of observed infrared light, is that of a swarm of cold, dusty comet fragments in a highly eccentric orbit.[12][13][14] Many small masses in "tight formation" orbiting the star have also been proposed.[9] The changes in brightness could be signs of activity associated wit…

Safe to say that a civilization that can build a Dyson structure isn't using any 20th-century coherent modulation types that SETI could detect.

SETI is only useful for catching civilizations in the ~100 Earth year-equivalent span between their development of wireless tech and information theory. There's nothing to listen to but white noise after that.

Re: Tabby's star is dimming at an incredible rate

#63

Post by olympusmons »

zackya89 wrote: post #16
aarmenante wrote: post #4

> In the meantime, we would remind you that it's very, very unlikely that this strange flickering star has anything to do with aliens (and is even more exciting if it doesn't - because, hello new space phenomena!). I think aliens would be a little bit more exciting... Might just be me though.

that headline though ?, online journalism at its worst, the chase for clicks, there really needs to be some solution to this problem journalism is dying and clickbait is where is at.

Lets brainstorm.

Perhaps one mathematical solution to the problem is to score pages based on the average time spent for each article. My hypothesis is that clickbait articles will score very low because the article will attract a lot of clicks from people who are not interested in the actual content but only the headline.

In theory, you could do this by deploying a tracker across the web similar to a Google analytics that performs the measurement. But in practice, of course, this isn't possible.

You might be able to approximate the score by building a browser extension that makes the measurement. A browser extension might also a good way to output results. It could, for instance, colour-code links (on mouseover) to help you spot click-bait before you click it!

Re: Tabby's star is dimming at an incredible rate

#64

Post by pygy_ »

peonicles wrote: post #59
fjarlq wrote: post #42

Earlier quoted context omitted.

Reddit user sigbjoernwilderness's idea is pretty wild... can it be easily ruled out? > Is this the last remaining explanation after Montet/Simon? > The dimming comes from the shadow of a spaceship traveling on an (almost) straight line from KIC8462852 to Earth. The slow continuous dimming results from the increase of the apparent size of the approaching ship while Earth/Kepler is in the penumbra. The irregular dips h…

There's a comment [1] in the other reddit thread that somewhat rules this out. > That doesn't even make sense when you're flying within the Solar System. Stuff moves, so you have to fly towards where it's going to be, not where it is. > The star is far enough away to be treated as a point source, with its light forming an apparent cone with the Earth's diameter. It doesn't intuitively make sense, at least to me, that…

It could be a way to announce their arrival passively.

Re: Tabby's star is dimming at an incredible rate

#65

Post by brownbat »

olympusmons wrote: post #63
zackya89 wrote: post #16

Earlier quoted context omitted.

that headline though ?, online journalism at its worst, the chase for clicks, there really needs to be some solution to this problem journalism is dying and clickbait is where is at.

Lets brainstorm. Perhaps one mathematical solution to the problem is to score pages based on the average time spent for each article. My hypothesis is that clickbait articles will score very low because the article will attract a lot of clicks from people who are not interested in the actual content but only the headline. In theory, you could do this by deploying a tracker across the web similar to a Google analytics…

There's a plugin for Wikipedia where if you hover over a linked term, it will show the first paragraph from that article, usually all you need.

We just need something like that for the web.

Re: Tabby's star is dimming at an incredible rate

#66

Post by akiselev »

david-given wrote: post #36
lucb1e wrote: post #31

Earlier quoted context omitted.

So what's the risk if it turns supernova in one year? As you say, it's 1500 ly away, not You sound way more expert on this than me (I had no idea lightyears had a notation, ly, nor that supernovas are dangerous to us as far as 50ly away), so I'll assume what you say is accurate, but I still see no imminent threat. I'm also not suggesting we'd have the full 1481 years, since we don't see what's presently there but wha…

Finding information on this appears to be kinda hard, but it looks like the best estimate for the 'kill radius' of a supernova (i.e. will cause mass extinctions) is 30 light years. So this is about two orders of magnitudes away, which means the effect will be two orders of magnitude lesser. Eta Corina is a double star containing at least one hypergiant that's going to go supernova any epoch now, so it gets studied a…

I believe the most powerful gamma ray bursts, the ones that are powerful enough to strip away our atmosphere at thousands of light years, are caused by superluminous supernovae (aka hypernovae) and weaker GRBs like the ones we usually see are caused by type 1c and 2b/n supernovae, although it is unclear whether they are different or closely related to hypernovae. The latter create long duration gamma ray bursts which last a lot longer than the usual burst and carry significantly more energy.

Re: Tabby's star is dimming at an incredible rate

#67

Post by api »

jimmytidey wrote: post #44
civilian wrote: post #40

Earlier quoted context omitted.

"Extraordinary claims require extraordinary evidence", and this is the weirdest star we've seen. Your claims of clickbait are out of line, because we really don't know and alien megastructures is a reasonable theory. And 'alien megastructures' isn't even the most ridiculous idea: https://www.reddit.com/r/KIC8462852/comments/4w7qfi/ben_mont...

This is an amazing theory. What could possibly be more out there than alien life? Alien life in a gigantic spaceship accidentally coming between you and a star.

Would it actually be a straight line?

Going from e.g. Earth to Mars does not consist of aiming for Mars and firing your rockets. It consists of hitting a parabolic transfer orbit and then doing another burn to place yourself in Mars' orbit -- or just heading right in if you've got the heat shields and retropropulsion for that. Basically you do orbital mechanics like Wayne Gretzky: you don't go to where the planet is, but where it's going to be.

Would interstellar flight be that different? Wouldn't you be executing a "transfer orbit" about the galactic center? Or is the effect of galactic-scale gravitational pull negligible there and you just end up basically going straight from A to B?

Edit: turns out this came from an actual subreddit dedicated to this star!

https://www.reddit.com/r/KIC8462852/

Subscribed!

Re: Tabby's star is dimming at an incredible rate

#68

Post by erdevs »

Good ol' PV on Kinja (from the linked gizmodo article: http://gizmodo.com/the-so-called-alien-megastructure-just-go...) has some interesting thoughts, as usual.

> The biggest axe against it being an alien megastructure project is the fact its an F-type star. F-types only live a couple billion years, depending on mass.

> But the drop in the radiant flux... a sustained drop. That could be something far more interesting. If you could do stellar engineering... you could draw the material off an F-type star while altering its core. You could reduce the mass to a G or K star, greatly increasing its lifespan... and gaining trillions upon trillions of tons of raw material with which to build an alien megastructure...

Re: Tabby's star is dimming at an incredible rate

#69

Post by golemotron »

simcop2387 wrote: post #18

Two reddit discussion that might be able to answer some questions we have here: https://www.reddit.com/r/Astronomy/comments/4waozn/new_paper... https://www.reddit.com/r/KIC8462852/comments/4w7qfi/ben_mont... They also contain links to the resulting paper itself

Tabby's Star has a twitter account also. It's unclear why no one is asking it direct questions about its intentions: https://twitter.com/KIC8462852

Re: Tabby's star is dimming at an incredible rate

#70

Post by Jill_the_Pill »

vmarsy wrote: post #57
jessaustin wrote: post #52

Earlier quoted context omitted.

The moon is smaller than the sun, and yet still we have eclipses. It's just a matter of perspective. The object[s] would have to be lined up. That's why an artificial object intentionally traveling to Earth is in some sense more plausible than an asteroid, which could be headed in any direction.

Why would it be only one object? It could be a belt of random sizes and shaped asteroids that is between us and the star?

Or the entire Vogon fleet?
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