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Tags astronomy , Tabby's Star

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Old 5th June 2017, 05:46 PM   #121
King of the Americas
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Originally Posted by Ziggurat View Post
That's not really true. This isn't a two-body problem. In a many-body problem, energy isn't a conserved quantity for any single body. That's how gravitational slingshots work: your space probe gains kinetic energy which it extracts from a planet that it passes by. Similar dynamics are in play here: the stuff which escapes the sun trades kinetic energy with the stuff that gets swallowed.
Yes, I get that, but the energy transfer is determined by angle of impact, and how far off-center from the bodies the collisions occur. A dead on, 90 degree impact of both centers would result in complete consumption of escape velocity energy. The two would become one. On the other end of the scale, the impact is one light, with most of the material keeping its velocity while remaining in orbit.

What we are seeing, right now, if it was a planetary consumption should be a brightening as the debris continues to fall, or solidify into a another formed mass or a flat disk-like ring.

The steady dimming indicates something other than planetary consumption...
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Old 5th June 2017, 05:51 PM   #122
Ziggurat
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Originally Posted by King of the Americas View Post
Yes, I get that, but the energy transfer is determined by angle of impact, and how far off-center from the bodies the collisions occur. A dead on, 90 degree impact of both centers would result in complete consumption of escape velocity energy. The two would become one. On the other end of the scale, the impact is one light, with most of the material keeping its velocity while remaining in orbit.

What we are seeing, right now, if it was a planetary consumption should be a brightening as the debris continues to fall, or solidify into a another formed mass or a flat disk-like ring.

The steady dimming indicates something other than planetary consumption...
No. The debris is in orbit, it isn't being consumed. It cannot cause brightening. And the time scale for coalescing may be quite long.
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Old 5th June 2017, 09:40 PM   #123
Myriad
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Originally Posted by Steve View Post
Excellent start. Please continue.

Okay.

Scary starry night
ETs building a Dyson Sphere
Klingon warships cruising near
In shadows of a killer asteroid
No way to avoid
Comets bringing a fiery fate
C-Beams near Tannhauser Gate
Directed by Darth Vader's dread command

Now I understand
Why you hide beneath the air
Amid the stars, darkness is everywhere
So have no doubt you must beware
When a star turns dim don’t go asking why
Assume you’re gonna die

Scary Starry night
Supernovas that brightly blaze
Lethal bursts of gamma rays
Reflect in the mad eyes of Elder Gods
Body snatcher pods
Monoliths evolve your race
So Xenomorphs can rape your face
While Martian tripods swarm across the land

Now I understand
Why you hide beneath the air
Amid the stars, evil is everywhere
So have no doubt you must beware
When a star turns dim don’t go asking why
Assume you’re gonna die

For something’s blocking your view
The starlight can’t pass through
And as you turn away in fright from that scary starry night
Some think they’re just researching something new
But I could have told you, humans
You must never forget how much the universe hates you

Scary starry night
Insane AIs that calculate
Viruses that replicate
On dead colony ships with zombie crews
Many dooms to choose
Black holes earth can fall into
Or nanobots turn it to goo
Bathed in a negative space wedgie’s glow

Now I think I know
Why we hide beneath the air
Between the stars, there’s nothing but despair
So I’ve no doubt I must beware
When a star turns dim I won’t question why
Just kiss my ass goodbye
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Last edited by Myriad; 5th June 2017 at 09:42 PM.
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Old 5th June 2017, 09:55 PM   #124
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Originally Posted by Myriad View Post
Okay.

Scary starry night
ETs building a Dyson Sphere
Klingon warships cruising near
In shadows of a killer asteroid
No way to avoid
Comets bringing a fiery fate
C-Beams near Tannhauser Gate
Directed by Darth Vader's dread command

Now I understand
Why you hide beneath the air
Amid the stars, darkness is everywhere
So have no doubt you must beware
When a star turns dim donít go asking why
Assume youíre gonna die

Scary Starry night
Supernovas that brightly blaze
Lethal bursts of gamma rays
Reflect in the mad eyes of Elder Gods
Body snatcher pods
Monoliths evolve your race
So Xenomorphs can rape your face
While Martian tripods swarm across the land

Now I understand
Why you hide beneath the air
Amid the stars, evil is everywhere
So have no doubt you must beware
When a star turns dim donít go asking why
Assume youíre gonna die

For somethingís blocking your view
The starlight canít pass through
And as you turn away in fright from that scary starry night
Some think theyíre just researching something new
But I could have told you, humans
You must never forget how much the universe hates you

Scary starry night
Insane AIs that calculate
Viruses that replicate
On dead colony ships with zombie crews
Many dooms to choose
Black holes earth can fall into
Or nanobots turn it to goo
Bathed in a negative space wedgieís glow

Now I think I know
Why we hide beneath the air
Between the stars, thereís nothing but despair
So Iíve no doubt I must beware
When a star turns dim I wonít question why
Just kiss my ass goodbye
Well done. Nominated.
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Old 12th June 2017, 03:28 PM   #125
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Just throwing it out there but what if the star isn't dimming but the energy is being sent somewhere else by a non artificial means? A truly odd wrinkle in space and time of sorts.
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Old 12th June 2017, 11:13 PM   #126
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Originally Posted by Travis View Post
Just throwing it out there but what if the star isn't dimming but the energy is being sent somewhere else by a non artificial means? A truly odd wrinkle in space and time of sorts.
Spacetime curvature obeys GR. We know how it works. "A truly odd wrinkle in space and time of sorts" would have to be accompanied by the matter/energy that causes that spacetime curvature. We also have good theoretical understandings of what is possible and what sorts of things are required for what sorts of curvature. For instance, we know what a black hole is. It wouldn't do what you are thinking. I can't think of anything that would.

Your suggestion basically comes down to "maybe it's gravity that's causing the dimming", but that's vague enough to be almost meaningless*, and I don't know of any specific way in which gravity would act like this.

*Ie. it's the kind of thought that you might take as a starting point for considering new ideas, but it's meaningless until you actually have those ideas.
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Old 16th June 2017, 12:50 PM   #127
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Hi Travis,

That would be one heck of a large mass to bend away the light from the star, generally black holes start around three solar masses, which would be fairly noticeable as it would create a binary system.

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Old 4th October 2017, 06:46 PM   #128
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NASA says there may be an explanation for the longer-period dimming, in the form of a dust cloud with a 700-day orbital period:

https://www.jpl.nasa.gov/news/news.php?feature=6963

Apparently, at least for longer periods, the dimming is different at different wavelengths, hence it's probably a dust cloud.
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Old 4th October 2017, 07:41 PM   #129
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Originally Posted by grmcdorman View Post
NASA says there may be an explanation for the longer-period dimming, in the form of a dust cloud with a 700-day orbital period:

https://www.jpl.nasa.gov/news/news.php?feature=6963

Apparently, at least for longer periods, the dimming is different at different wavelengths, hence it's probably a dust cloud.

That's no fun.

I like alien mega-structures better, so I'm going with that.
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Old 4th October 2017, 07:50 PM   #130
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Originally Posted by quadraginta View Post
That's no fun.

I like alien mega-structures better, so I'm going with that.
Exactly the type of thinking that keeps this forum interesting.
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Old 5th October 2017, 12:23 AM   #131
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NASA party-poopers.
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Old 5th October 2017, 12:54 AM   #132
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Next question is what caused the dust to be there in the first place? And why is it uneven? Maybe it was created recently, maybe by a space ship that blew up the planet like in star wars. Or maybe not.
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Old 5th October 2017, 01:42 AM   #133
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Originally Posted by Puppycow View Post
NASA party-poopers.
http://www.gocomics.com/nonsequitur/2009/01/19/
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Old 5th October 2017, 01:54 AM   #134
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Originally Posted by quadraginta View Post
That's no fun.

I like alien mega-structures better, so I'm going with that.
The dust cloud only addresses the long term dimming. Still scope for mega-structures for the short-term stuff.
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Old 5th October 2017, 12:00 PM   #135
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Originally Posted by sphenisc View Post
The dust cloud only addresses the long term dimming. Still scope for mega-structures for the short-term stuff.
Dusty megastructures. Need a good cleaning.
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Old 5th October 2017, 02:02 PM   #136
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Originally Posted by Steve View Post
Dusty megastructures. Need a good cleaning.

If there's anything that disgusts me it's dusty mega-structures.

And once the neglect starts there's no stopping it. Before long you end up with solar reflector panels flying loose, mono-molecular wire strewn everywhere, ...

It's a recipe for disaster, I say!
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