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New Class of "Hypervelocity Stars" Discovered Escaping the Galaxy

samzenpus posted about 7 months ago | from the greased-lightning dept.

Space 150

Science_afficionado writes "Astronomers have discovered a surprising new class of 'hypervelocity stars' that are moving at more than a million miles per hour, fast enough to escape the gravitational grasp of the Milky Way galaxy. The 20 hyper stars are about the same size as the sun and, other than their extreme speed, have the same composition as the stars in the galactic disk. The big surprise is that they don't seem to come from the galaxy's center. The generally accepted mechanism for producing hypervelocity stars relies on the extreme gravitational field of the supermassive black hole that resides in the galaxy's core."

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150 comments

Maybe they're not stars.... (1)

Anonymous Coward | about 7 months ago | (#45913045)

Maybe they're motherships :D

Re:Maybe they're not stars.... (3, Funny)

Cryacin (657549) | about 7 months ago | (#45913075)

Maybe those starts just didn't like the neighbourhood they were in and decided to move house.

What's pulling/pushing the stars ? (1, Troll)

Taco Cowboy (5327) | about 7 months ago | (#45914139)

Maybe those starts just didn't like the neighbourhood they were in and decided to move house

TFA only says that the stars are travelling at a speed high enough that they can escape the pull of the galaxy, but doesn't give any explanation of WHAT is pushing or pulling the stars.

From TFA:

"The generally accepted mechanism for producing hypervelocity stars relies on the extreme gravitational field of the supermassive black hole that resides in the galaxy's core"

If it's the "supermassive black hole in the Galaxy core" that's doing the pulling, the stars should have travelling towards the core.

But they are travelling instead away from the core !

Instead of a "pull", it is as if there's something that's "PUSHING" them instead, and I do not think it's the supermassive blackhole (whose expertise is on the pulling part).

Re:What's pulling/pushing the stars ? (4, Informative)

znanue (2782675) | about 7 months ago | (#45914535)

Due to inertia, the stars would continue to travel at their current speeds if nothing were pushing and pulling on them. As it is, whatever gravitational forces are acting upon them at the moment might be comparatively insignificant to their current inertia.

So how did they get their current inertia? They might have gotten it from the supermassive black hole at the galaxy's core without setting their vector towards the core. They could do so possibly using a gravity slingshot effect [discovery.com] . So it is surprising they're not coming from the core, as the article states. So what is interesting about these stars is they don't seem to be explained by the slingshot effect.

Further, gravity is a force of attraction and so does no pushing.

Also, I did a knapkin calculation of the speeds involved and it would be 1/700th the speed of light except the article says that this speed is relative to the movement of the galaxy and not an absolute speed like the slashdot summary intimates.

Re:What's pulling/pushing the stars ? (4, Informative)

Anonymous Coward | about 7 months ago | (#45914837)

There is no such thing as "absolute speed"; all movement is relative to other objects in the universe.

Re:What's pulling/pushing the stars ? (-1)

Anonymous Coward | about 7 months ago | (#45915277)

Oh, according to current theories there is "absolute speed". If I move at lightspeed to the right, and switch on a flashlight pointing left, and i pass some observer right at the time when i switch the light on, the observer sees me going at light speed and the light going at lightspeed to the other direction. At the same time I see the light going away from me at lightspeed. That's how it works. It feels absolutely wrong. It might even be wrong for all I know, but many scientists say it's like this.

Re:What's pulling/pushing the stars ? (0)

Anonymous Coward | about 7 months ago | (#45916459)

If in principle you could move at the speed of light, than so can other observers meaning relative to some observer you would appear to not be moving, and there still would not be an absolute speed frame. But observers can't reach speed of light under special relativity, and not while in your past light cone in general relativity. Even if you could go speed of light relative to someone else, all distances in the other person's frame would contract to zero distance in your frame, so there would be no moment or place where you could turn on a flash light, as you would appear to instantly move from point A to point B for any point A and B in the other person's frame.

Re:What's pulling/pushing the stars ? (0)

Anonymous Coward | about 7 months ago | (#45916497)

You sound like an imbecile. Either learn to explain things properly, or keep your ill-formed thoughts to yourself.

It's the Reptiles (0)

Anonymous Coward | about 7 months ago | (#45915599)

They're starting to take control of the universe, so those that have the technology create singularities to kick their star systems into an escape escalator.

Re:Maybe they're not stars.... (5, Informative)

icebike (68054) | about 7 months ago | (#45913251)

A million miles per hour is not all that much.

All the galaxies in our neighborhood are also rushing at a speed of nearly 1,000 kilometers per second (2,236.936 miles per hour) towards a structure called the Great Attractor, a region of space roughly 150 million light-years away.

In addition, our solar system--Earth and all--whirls around the center of our galaxy at some 220 kilometers per second, or 490,000 miles per hour.

The earth is moving toward the Constellation Leo at the dizzying speed of 390 kilometers per second. (872,405 miles per hour).

Lots stuff going places fast.

Now if you find an inhabitable planet orbiting one of these stars let me know. That would be the mothership of all motherships.

Re:Maybe they're not stars.... (2)

SJHillman (1966756) | about 7 months ago | (#45913387)

"1,000 kilometers per second (2,236.936 miles per hour)"

Either kilometers are a lot shorter than I remember, or you got your periods and commas mixed up somewhere.

Re:Maybe they're not stars.... (2)

icebike (68054) | about 7 months ago | (#45913413)

Should have been all commas. Doh.
At least for those of us on this side of the pond.

Re:Maybe they're not stars.... (0)

Anonymous Coward | about 7 months ago | (#45913435)

Wrong. Hours could be shorter.

Only redarted start people smart sentences with a one word negative. ;P

Re:Maybe they're not stars.... (3, Insightful)

Charliemopps (1157495) | about 7 months ago | (#45913409)

Now if you find an inhabitable planet orbiting one of these stars let me know. That would be the mothership of all motherships.

Or really bad luck. Leaving the galactic plane would pretty much assure your species would never branch out beyond your own solar system.

Re:Maybe they're not stars.... (1)

icebike (68054) | about 7 months ago | (#45913493)

Maybe they already did that.

Like the GP suggested: Motherships.
What better space ship can you conceive of than traveling with an entire solar system?
Who knows how many worlds they might have seeded.

Some seem to be passing by our neighborhood. Mom? Where are you going?

Re:Maybe they're not stars.... (2)

Charliemopps (1157495) | about 7 months ago | (#45917001)

yea, but they are headed in the wrong direction, and are moving REALLY slow. If we saw stars moving around at a few percent the speed of light, then maybe. But a million miles per hour? That's 0.0014% the speed of light. Our closest neighbor is 25.8 trillion miles away. So it would take them nearly 3 thousand years just to get there. Not much of a mother ship.

Re:Maybe they're not stars.... (1)

cusco (717999) | about 7 months ago | (#45917357)

Who says that 70 years is the maximum average lifespan for sentient beings? We may be abnormally short-lived, and 3000 years might not be an unreasonable time for an explorer to spend on an epic voyage. Yeah, not really applicable here, but it's an objection that I always hear as to why interstellar flight is impossible.

Re:Maybe they're not stars.... (2)

Rotaluclac (561178) | about 7 months ago | (#45914971)

Or really bad luck. Leaving the galactic plane would pretty much assure your species would never branch out beyond your own solar system.

But the view of the Milky Way would be gorgeous!

Re:Maybe they're not stars.... (0)

Anonymous Coward | about 7 months ago | (#45915387)

but the view in pretty much any other direction would be pretty dull.

Re:Maybe they're not stars.... (5, Funny)

camperdave (969942) | about 7 months ago | (#45913693)

Everybody sing!

Just remember that you're standing on a planet that's evolving
And revolving at nine hundred miles an hour,
That's orbiting at nineteen miles a second, so it's reckoned,
A sun that is the source of all our power.
The sun and you and me and all the stars that we can see
Are moving at a million miles a day
In an outer spiral arm, at forty thousand miles an hour,
Of the galaxy we call the 'Milky Way'.
Our galaxy itself contains a hundred billion stars.
It's a hundred thousand light years side to side.
It bulges in the middle, sixteen thousand light years thick,
But out by us, it's just three thousand light years wide.
We're thirty thousand light years from galactic central point.
We go 'round every two hundred million years,
And our galaxy is only one of millions of billions
In this amazing and expanding universe.

The universe itself keeps on expanding and expanding
In all of the directions it can whizz
As fast as it can go, at the speed of light, you know,
Twelve million miles a minute, and that's the fastest speed there is.
So remember, when you're feeling very small and insecure,
How amazingly unlikely is your birth,
And pray that there's intelligent life somewhere up in space,
'Cause there's bugger all down here on Earth.

Re:Maybe they're not stars.... (2, Informative)

Anonymous Coward | about 7 months ago | (#45914413)

Those are cool lyrics.. did you write that yourself?
Don't be an Apple...

  - Galaxy Song Lyrics by Monty Python

interesting (0, Interesting)

Anonymous Coward | about 7 months ago | (#45913703)

So, what you are saying is that these so-called 'Hypervelocity' stars are actually no different from others stars in our galaxy, just that somehow their velocity has been given a new direction, like a rubber ball bouncing off a wall.

The significance of this is that no new accelerating energy source is required in theory, since the 'rogue' stars already had the same mount of momentum energy as their 'normal' neighbours. Of course, we don't know what phenomenon would 'bounce' these stars into a new direction. It would be reasonable to think we may be seeing the result of some 'intelligent' action- a star-system scale project of engineering.

It would be of interest to consider the objects in the future path of such stars. Were these mere random natural events, one would expect that the contents of space in front of these stars would be completely random. However, if the forward paths show content that cannot be described as random, this increases the likelihood that these stars were given their new direction on purpose.

 

Re:interesting (4, Informative)

icebike (68054) | about 7 months ago | (#45914271)

Nah, I'm not speculating on where they got their energy at all.

Just pointing out that "million miles per hour" is not unusual in this universe, and therefore escape velocity is not that hard to achieve.
All it would take is galaxies spinning at different angles passing each other to spit off a few stars from the fringe edge. In fact the edge is probably ragged precisely because stars are occasionally spun off, like the outside skater roller derby.

Re:interesting (1)

interkin3tic (1469267) | about 7 months ago | (#45917095)

All it would take is galaxies spinning at different angles passing each other to spit off a few stars from the fringe edge.

Isn't it known whether galaxies are close enough for that to be a factor? TFA doesn't say "and it's right next to the closest galaxy, so that's probably the reason." Furthermore, galaxies are mostly empty space, so it seems like how individual stars would interact to spin each other out would still be an interesting observation problem.

Re:Maybe they're not stars.... (-1)

Anonymous Coward | about 7 months ago | (#45913721)

All the galaxies in our neighborhood are also rushing at a speed of nearly 1,000 kilometers per second (2,236.936 miles per hour) towards a structure called the Great Attractor

You may call it the Great Attractor, but the rest of us call it your Mamma!

Re:Maybe they're not stars.... (4, Informative)

Maow (620678) | about 7 months ago | (#45914417)

A million miles per hour is not all that much.

All the galaxies in our neighborhood are also rushing at a speed of nearly 1,000 kilometers per second (2,236.936 miles per hour) towards a structure called the Great Attractor, a region of space roughly 150 million light-years away.

I think they're calling them fast based on the relative speed to the galaxy that they're being ejected from / passing though.

Astrophysicists calculate that a star must get a million-plus mile-per-hour kick relative to the motion of the galaxy to reach escape velocity.

The diagram in TFA seems to indicate that these stars are not originating inside the galaxy, which to me raises the question, from whence do they come?

This image [vanderbilt.edu] makes it appear the stars are mostly passing through the disk of the galaxy. I may be reading too much into the length of the coloured lines though.

Re:Maybe they're not stars.... (0)

Anonymous Coward | about 7 months ago | (#45915463)

They likely came from the last galaxy collision we had that formed our current galaxy.
As you know, most galaxies around now are formed from countless galaxy collisions that have piled up over the billions of years.

And we are about to have another one happen in the future too. We are about to welcome another few billion/trillion friends to the galaxy.
Shame we won't be around to see it.
Even if it was disastrous, it would still be amazing as fuck to see a huge ass star about to come wipe us out at 1500km/s. brb mountain so I can watch in peace.

Re:Maybe they're not stars.... (3, Interesting)

Vitriol+Angst (458300) | about 7 months ago | (#45915943)

They are likely wandering stars from another galaxy. Wasn't it estimated that we already had one galaxy pass through the Milky Way and sometime in the future we may pass through Andromeda?

So perhaps there are three mechanisms for high speed stars;
1) ejected by a super massive black hole.
2) remnant of non-colliding stars from Galactic collisions (and actually, most stars don't hit each other in these situations).
3) L3 advanced civilization finding that solar tourism is more fun if you can take all your stuff with you.

3-body chaotic gravity assist (4, Insightful)

Katatsumuri (1137173) | about 7 months ago | (#45914787)

One of the theories for the origin of these hypervelocity stars is 3-body chaotic gravity assist. When two bodies are entering a gravity assist trajectory around a third, very massive body, their interactions sometimes add up in such a way that one body falls into a tight orbit, and another is ejected at a hypervelocity. Given the number of ternary star systems in the galaxy, this looks like a plausible explanation.

There is even a paper suggesting we could build an interstellar starship from two asteroids [prescientmodels.com] (PDF, 10 pages) using this mechanism. It was written by Josef L Breeden and presented at the 100 Year Starship conference.

Re:Maybe they're not stars.... (5, Funny)

meerling (1487879) | about 7 months ago | (#45913263)

It's not the Puppeteer Homefleet, they aren't flying in formation.

(If you don't know what I'm talking about, look up author Larry Niven.)

Re:Maybe they're not stars.... (1)

jeffb (2.718) (1189693) | about 7 months ago | (#45913517)

It was reminding me of the Fast Protosun. Of course, there's a big gap between 10^6 mph and 0.8c. Not to mention a number of other likely differences (not least because they would be spoilers).

Re:Maybe they're not stars.... (0)

Anonymous Coward | about 7 months ago | (#45914693)

Perhaps you should revisit those books yourself. Not the ones actually called "Fleet of Worlds", though, they're pretty... meh.

Stop them they are excaping criliminals.! (1)

For a Free Internet (1594621) | about 7 months ago | (#45913049)

These starts are triying to excape from jusitse but yhey wile not! SLASHDORT ASSGAS!

OMG! Marshall Applewhite! (1)

retroworks (652802) | about 7 months ago | (#45913057)

Heavens Gate was right all along! We missed the Mothership, guys!

Friederich Pohl was right all along... (3)

Anonymous Coward | about 7 months ago | (#45913085)

This is obviously 'Wan-to' up to his old tricks again.

Re:Friederich Pohl was right all along... (0)

Anonymous Coward | about 7 months ago | (#45913109)

The World at the End of Time was a great book!

Evidence of Intelligent Life (0)

Anonymous Coward | about 7 months ago | (#45913087)

Maybe this is evidence of an advanced civilization.

Re:Evidence of Intelligent Life (2)

NoNonAlphaCharsHere (2201864) | about 7 months ago | (#45914299)

It's evidence Chuck Norris roundhouse kicked them out of HIS galaxy.

it's not the star that is moving it's the space. (0)

Anonymous Coward | about 7 months ago | (#45913107)

space is not limited by the speed of light. What is the matter with you people?

Re:it's not the star that is moving it's the space (1, Informative)

Anonymous Coward | about 7 months ago | (#45913461)

space is not limited by the speed of light. What is the matter with you people?

Nothing is limited by the speed of light. The galactic constant is a phenomenon, not a limiting force.

The Puppeteers Are Leaving! (1)

Anonymous Coward | about 7 months ago | (#45913111)

They've spotted the explosion! Get in your General Products Hull and run for it! Our only salvation will be to find the Ringworld and move it out of the galaxy!

Re:The Puppeteers Are Leaving! (2)

rossdee (243626) | about 7 months ago | (#45913807)

Moving the Ringworld is not the problem, getting the star to go along with it might be though.

Re:The Puppeteers Are Leaving! (1)

Eddi3 (1046882) | about 7 months ago | (#45914667)

You have clearly not read the books.

Re:The Puppeteers Are Leaving! (0)

Anonymous Coward | about 7 months ago | (#45914709)

Nor, it seems, have you. Before Tunesmith started spreading magic dust everywhere the plan was to turn the sun into a fusion engine. It would have been a better option (no monsters taking bites out of the rim for one thing) if not for the fact that most of the species of Known Space were figuratively banging at the door.

Assuming ... (5, Interesting)

TrollstonButterbeans (2914995) | about 7 months ago | (#45913141)

Assuming the observation gets studied and confirmed, this is probably far more common than one might initially expect.

The Milky Way has been on the move billions of years and occasionally meets up with star clusters or even dwarf galaxies.

Many of them probably settle in gravitationally, but some of them aren't going to and continue, largely, about their merry way if the relative speeds are right.

These stars could have been "acquired" 400 million years ago and it can take a long time to traverse a cross-segment of the Milky Way. And these stars would have to be smaller like our sun to have the right lifespan, and we wouldn't notice the really small ones (red dwarfs and such) because they would be hard to see so there is also a mix of observational factors in the equation.

Re:Assuming ... (2)

bob_super (3391281) | about 7 months ago | (#45913267)

Beat me to the hypothesis. Just because a star is in the milky way doesn't mean that it was formed there. It may just be passing by, with its doors locked and hoping to look inconspicuous because it's got a similar composition as the local hot hooligans (how likely is that? that's not specified in TFS)

Re:Assuming ... (1)

TMB (70166) | about 7 months ago | (#45913947)

Except that if the star was captured by the Milky Way, that already tells you that it was moving at less than the escape velocity, while these are moving faster than the escape velocity.

Still, it would be interesting to see if they share orbital elements with known satellites or streams...

[TMB]

Re:Assuming ... (1)

Anonymous Coward | about 7 months ago | (#45915775)

TFA says that those stars appear to have the same composition as normal disk stars, so they cannot come from dwarf galaxies.

Also, traversing the disk at 'hypervelocity' takes definitely less than 400 million years. Mind that our Sun takes just half that go around the disk at about half its diameter and at a regular velocity.

Re:Assuming ... (1)

interkin3tic (1469267) | about 7 months ago | (#45917215)

TFA says these were calculations done on the Sloan Digital Sky Survey data, which was released to the world in 2008 according to their homepage, so the actual observations are already "confirmed" in that sense. I'm assuming the current study released their calculations and methods so anyone can double check them.

Weeee... (0)

Anonymous Coward | about 7 months ago | (#45913215)

....eeeeeeee!

There goes the Big Bang Theory (0)

Anonymous Coward | about 7 months ago | (#45913229)

I never believed in it, anyway.

Re:There goes the Big Bang Theory (5, Funny)

Scarletdown (886459) | about 7 months ago | (#45913397)

I never believed in it, anyway.

You probably don't believe in Monk, Night Court, or All In the Family either.

slingsot (1)

deodiaus2 (980169) | about 7 months ago | (#45913245)

Maybe two super-massive black holes passed close to each other and spun these off?

Re:slingsot (2)

tftp (111690) | about 7 months ago | (#45913455)

Maybe two super-massive black holes passed close to each other and spun these off?

Perhaps. But now instead of explaining why one common star is moving somewhere fast you need to explain why two uncommon black holes are moving somewhere fast, and on top of that why they nearly hit each other and some common star...

Not the only supermassive black hole... (4, Interesting)

Rick in China (2934527) | about 7 months ago | (#45913259)

Looking at the trajectories, wouldn't it be a possibility that these stars didn't originate in our galaxy, but rather, could have been tourists flung out in a similar fashion from another supermassive black hole outside of our own galaxy? Just passing through on various trajectories, from potentially various other galaxies. Not much thought put into this - maybe the distance from the nearest supermassive black hole outside of our own galaxy makes this an impossibility, but seems the article doesn't go into any theories at all.

The question is (1)

zakeria (1031430) | about 7 months ago | (#45913285)

what the hell is chasing it?

Alien physics experiments (1)

HalfFlat (121672) | about 7 months ago | (#45913289)

They're just trying to see what they can get away with with a Newtonian approximation of gravity [io9.com] .

This makes me think more about the word "Speed" (3, Interesting)

BringsApples (3418089) | about 7 months ago | (#45913311)

Aren't all objects' movement (speed) based on another objects movement (speed)? I mean, how fast is the Milky Way moving, and in what direction? And could that star just be sitting idle-ish, and our galaxy zipping past it? Are these question answerable?

Re:This makes me think more about the word "Speed" (5, Informative)

Uecker (1842596) | about 7 months ago | (#45913437)

If one considers the rest frame of the microwave background as the rest frame of the universe, then yes, one can answer these questions.

http://en.wikipedia.org/wiki/Cosmic_microwave_background [wikipedia.org]

Re:This makes me think more about the word "Speed" (0)

Anonymous Coward | about 7 months ago | (#45914205)

Doesn't CMB consist of photons? They always move at the speed of light regardless of the reference frame you pick. How can you use them as a reference frame?

Re:This makes me think more about the word "Speed" (5, Informative)

Uecker (1842596) | about 7 months ago | (#45914257)

Due to the Doppler effect, you see the frequency shift if you move relative to the microwave background, which would otherwise be (almost) the same blackbody radiation of temperature 2.725 K from all direction.

Re:This makes me think more about the word "Speed" (1)

Vitriol+Angst (458300) | about 7 months ago | (#45915899)

But why is the background radiation ALREADY Doppler shifted? In other words; our solar system and galaxy are moving at a high rate of speed already -- so there should already be a Doppler effect.

So is there a "relativistic lens" of the space we are in that normalizes the shift we see?

I get that we see a Doppler shift if we quickly moving in a given vector -- I'm just curious why we don't see more effects from the vectors we are already moving in. It suggests that space is a "thing" and in many cases, it is moving us -- as though it has a current.

Re:This makes me think more about the word "Speed" (0)

Anonymous Coward | about 7 months ago | (#45917549)

I thought if you are moving near the same relative speed, you don't see a Doppler shift.

Re:This makes me think more about the word "Speed" (0)

Anonymous Coward | about 7 months ago | (#45913477)

this makes me think you are taking speed.

Re:This makes me think more about the word "Speed" (2)

Shavano (2541114) | about 7 months ago | (#45913505)

You're missing the point. These are stars moving at at abnormal speeds and can't be explained by any phenomenon we have observed before.

Re:This makes me think more about the word "Speed" (4, Interesting)

camperdave (969942) | about 7 months ago | (#45913669)

You're missing the point. These are stars moving at at abnormal speeds and can't be explained by any phenomenon we have observed before.

Every gravity simulation I've ever run has had a few objects flung off at high speed. It doesn't take a lot.

Re:This makes me think more about the word "Speed" (0)

Anonymous Coward | about 7 months ago | (#45913875)

These are *stars*, not planets. It takes quite a lot more than just skipping a rock around Jupiter's orbit.

Re:This makes me think more about the word "Speed" (1)

Anonymous Coward | about 7 months ago | (#45913921)

Okay, then how much would it take to fling Miley Cyrus out of the galaxy at millions of miles per hour?

Re:This makes me think more about the word "Speed" (3, Funny)

Metabolife (961249) | about 7 months ago | (#45914027)

A wrecking ball.

Re:This makes me think more about the word "Speed" (0)

Anonymous Coward | about 7 months ago | (#45915585)

She'd probably try to mate with it.

Re:This makes me think more about the word "Speed" (2, Informative)

Anonymous Coward | about 7 months ago | (#45914143)

There are plenty of stars in the galaxy that would make our star look like a rock next to jupiter.

Re:This makes me think more about the word "Speed" (2)

Katatsumuri (1137173) | about 7 months ago | (#45914797)

Exactly. See also my post above about 3-body chaotic gravity assist [slashdot.org] .

Re:This makes me think more about the word "Speed" (2)

fatphil (181876) | about 7 months ago | (#45915985)

I recommenda 4th/5th-order Runge-Kutta extrapolation. It's so stable, I managed to model satelites which would move a quarter of an orbit per time step and not fly off to infinity. Simple 1st/2nd order extrapolation doesn't cut it - you'll end up with two things exceptionally close one tick, and then zipping away unimaginably quickly the next tick.

Re:This makes me think more about the word "Speed" (1)

BringsApples (3418089) | about 7 months ago | (#45914801)

I may be missing the point. You tell me at what "speed" the Milky Way is moving, and I'll figure the rest out by myself.

The point (0)

Anonymous Coward | about 7 months ago | (#45916343)

The point is these are two WOMEN who found these most amazing and special super speed stars.

Re:This makes me think more about the word "Speed" (0)

Anonymous Coward | about 7 months ago | (#45913715)

Thank you.

Re:This makes me think more about the word "Speed" (3, Informative)

KliX (164895) | about 7 months ago | (#45914239)

'Relative' is the key. There is no fixed background to say 'This is going absolutely this fast', any observation point in any kind of motion is as viable as any other. It just falls out of a little bit of simple vector maths - so no, your question is not answerable, as it's malformed.

Re:This makes me think more about the word "Speed" (1)

Vitriol+Angst (458300) | about 7 months ago | (#45915743)

I'm sure there have been some tests, but has anyone conclusively found a "vector" to space? Currently, we use Universal Background Radiation -- allegedly this is the noise left over from the poorly named "Big Bang".

The problem of Relativity is that either their is a universal time or all time is local -- and each object has a relative time displacement to each other. In the simple model of relativity, you have an observer, or someone leaves a planet at high speed and comes back and their clocks have accounted for less time than people who "stayed behind." But we don't really know if there is a "vector to space" in that the planet they leave may be traveling faster or "against" the motion of space, and the rocket is actually moving slower by traveling in a direction opposite to this.

So a test for this would be to have perhaps 6 rockets move at the same rate of speed (as best as can be determined), in the absence of a gravity field (as best as can be found), and if they move at relativistic speeds and make a return to the same location -- there is either a vector that required more energy because they were moving in opposition to the background motion of space, or they have relatively the same time displacement and energy output.

The results would not be trivial.

I predict that while there is no real condition for an "outside observer" -- that space itself can have a vector -- that means it's not just a blank emptiness but actually a thing. Like Dark Matter -- but not. Dark Matter I think is a manifestation of "turbulence" in Space itself and suggests that gravity and mass have a frequency and indirect impact on space that we have yet to discern. To make this clearer -- if all the spacecraft are moving "in a block" of space time -- then they will not have a difference in relative energy output and time - acceleration alone accounts for "relativity". However, the are in a Solar System, Galaxy and Galactic Cluster that all move at the same time in different directions.

The current theory of relativity SHOULD support different displacements for each rocket -- and thus a "zero motion" state can be deduced by factoring in the relativistic effects. However, I feel like Classic Relativity kind of breaks down in different vectors and each object has it's own "time". The oversight seems to be that many people are only using a few simple vectors when they think of relativity. But I imagine particles in a star bouncing around at nearly light speed -- they are moving from an object both at nearly light speed, and then hitting other objects at nearly light speed -- so relativity in that situation is spaghetti. Depending on the direction particles are both speeding up and slowing down relative to other particles. Space/Time is both stretched and compressed at the same location.

The point is that even relativity is relative, and it has to mean we've got quite a few more dimensions involved in this 4 dimensional world we think we inhabit. Objects have to be moving in other vectors in other dimensions to resolve "normality" as far as we are concerned.

Correct, but could be phrased better (0)

Anonymous Coward | about 7 months ago | (#45914495)

You were right in your basic premise that all speed is relative, so it's just as accurate to say that these stars are wizzing through the galaxy at hypervelocity as it is to say that the galaxy is wizzing through those stars' neighborhoods at hypervelocity.

You were however taken to task for using phrases like "sitting idle-ish" which suggest an absolute frame of reference, which is of course wrong.

Note that the Andromeda Galaxy is heading in our direction at around 300 kilometers per second (a bit less than 1 million mph), so a high proportion of our galaxy's stars will be "hypervelocity stars" from its perspective (and vice versa) when it finally reaches us in around 4 billion years' time.

Re:Correct, but could be phrased better (0)

Anonymous Coward | about 7 months ago | (#45915511)

Note that the Andromeda Galaxy is heading in our direction at around 300 kilometers per second (a bit less than 1 million mph), so a high proportion of our galaxy's stars will be "hypervelocity stars" from its perspective (and vice versa) when it finally reaches us in around 4 billion years' time.

It won't reach us. The universe expansion accelerates, so the apparent speed between us and Adromeda will slow down, stop, and start going the other way within that time (which is substantial - it's nearly a third of the current age of the universe as seen from here).

Re:Correct, but could be phrased better (0)

Anonymous Coward | about 7 months ago | (#45916311)

But the distance is very small cosmologically speaking, and in a time of about +/- 5 billion years, the universe doesn't look like it is accelerating very much and is very difficult to distinguish from a constant expansion or deceleration. Noticeable impact on such scales won't happen until time scales of 10s of billions of years.

Re:This makes me think more about the word "Speed" (3, Informative)

idji (984038) | about 7 months ago | (#45914563)

This speed is still very fast if it is taken relative to us or to the galactic center. The galaxy's speed relative to the cluster plays no role at these sizes and time scales. "sitting idle-ish and the galaxy zipping past" is the classic Relativity - it makes no difference - both are identical. In either case something caused that Star's velocity relative to us to by very different.

Re:This makes me think more about the word "Speed" (1)

Kjella (173770) | about 7 months ago | (#45915021)

I think it theory you can use the fact that c is constant to prove your absolute speed. Imagine you send a single photon down both ends of a tube and measure where they meet. You know both photons have travelled at the same speed and so covered the same distance. Imagine your ship travels at 0.5c and the tube is 100cm, in the time it takes the photons to cover 50cm each your ship will have moved 25cm so they actually meet at 75/25cm not 50/50cm as you'd expect. Get a perfect 50/50cm in three axis and you will have proved that the relative speed between you and the photons is c and thus your absolute speed must be c - c = 0.

I guess (3, Funny)

Anonymous Coward | about 7 months ago | (#45913531)

the radio waves with Fox News started reaching them.

Re:I guess (0)

Anonymous Coward | about 7 months ago | (#45913783)

awww, -1... I thought it was funny.

Re:I guess (0)

Anonymous Coward | about 7 months ago | (#45914543)

It is funny, you were down modded by the Faux News sockpuppets

Cool guess (0)

Anonymous Coward | about 7 months ago | (#45913537)

Maybe those are not just stars, but civilizations of Type II on Kardashev's scale.
I mean those guys: https://en.wikipedia.org/wiki/Kardashev_scale#Definition

Astronomers get a clue (1)

die standing (2626663) | about 7 months ago | (#45913549)

those aren't stars escaping the galaxy... those are golf balls being hit by people that watched those 8 free HD golf lesson videos to learn that weird golf trick to add an extra 20 yards.

Miles per Hour and Inferiority Complexes (0)

Mister Liberty (769145) | about 7 months ago | (#45913579)

Ah -- all those sorry imperia that are reminded of when their deficient units of measurement find
their only shelter in planetary travel and galactic theories.
Is the galaxy Anglosaxon? No, all rejoice -- it is not.

We know what this is. (1)

koan (80826) | about 7 months ago | (#45913633)

Puppeteer planets escaping.

#PaulWalker (0)

Anonymous Coward | about 7 months ago | (#45913833)

Too soon?

Next assignment (2)

symbolset (646467) | about 7 months ago | (#45913845)

From the ratio of stars being ejected, get the average rate of galaxy evaporation. Calculate backward to compute original mass of the milky way.

It's obvious (2)

93 Escort Wagon (326346) | about 7 months ago | (#45913909)

These stars were ejected by the polar vortex.

Could just be gravitational sling-shotting... (1)

Anonymous Coward | about 7 months ago | (#45914171)

I'd think an N-body problem with 300 billion stars would almost inevitably produce a few stars that just by chance get a sufficient number of gravitational slingshots from other stars that they get up to escape velocity...

Those aren't stars... (1)

surfdaddy (930829) | about 7 months ago | (#45914389)

Those are spaceships!

Somebody stop them! (3, Funny)

locopuyo (1433631) | about 7 months ago | (#45914419)

Somebody stop them!

Questions for people that could do the math (1)

istartedi (132515) | about 7 months ago | (#45914447)

What would happen if one of these beasts passed near the Solar system. For "near" consider the following scenarios: 1. Oort cloud. 2. Kuiper belt (I don't recall which one is closer and I'm too lazy to google it). 3. Just outside the orbit of Neptune. 4. Collision with Jupiter. 5. A passage inside the orbit of Mercury, no planetary collision or collision with Sol.

Finally, assuming none of these scenarios killed us by disruption the relationship between the Earth and Sun or flinging large bodies at us, how practical would it be to use a gravitational slingshot to launch a probe at high velocities?

Mark (0)

Anonymous Coward | about 7 months ago | (#45914657)

Wow. You guys are a bunch of fuckin nerds.

Kelly is fuckin hot!

Relocating (0)

Anonymous Coward | about 7 months ago | (#45914795)

Easy, they're relocating [slashdot.org] ... probably to avoid some new hyperspatial express route.

Re:Relocating (1)

Prof.PatPending (1603155) | about 7 months ago | (#45916415)

Maybe the "UFOs" we've been seeing for the last couple of centuries are scout craft for these star systems, making sure there's no civilizations along their path that could cause trouble.
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