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Star Flung From Milky Way at High Speed
fenimor writes "Using the MMT Observatory in Tucson, astronomers have discovered a star three times bigger than the sun, leaving our galaxy at a speed of over 1.5 million miles per hour (670 kilometers per second). The first-of-its-kind finding not only confirms an earlier theory about the existence of such speeding stars, but also reinforces the notion that the Milky Way spins around a black hole."
It's a glider!
--
make install -not war
"We're tempted to call it the outcast star because it was forcefully tossed from its home."
Instead they are going to call it a galaxy challenged star.
It could be worse, it could be Monday.
galactic pin ball here we come!!
Just like my screen saver predicted.
A programmer is a machine for converting coffee into code.
Ok, now how do we apply this knowledge to do the same to Microsoft/Paris Hilton/Terrel Owens/Celine Dion.... ?
If everything around it is also moving that fast and in the same direction, then from the star's frame of reference, it's standing still.
Starlight, star bright, first-of-its-kind star I see tonight, I wish I may, I wish I might, get laid tonight.
Do your best, hope for the best, suspect the worst.
I think he might have meant if we were to be run over by a random sun moving at that speed. Could be wrong, though.
What are they measuring the star's speed against? The center of our galaxy? The earth?
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
It's relative speed to us (eg. the sun, or any other mass).
In the void of space this has no consequences for the mass that is speeding. (Until it collides with something that has a different speed.)
Abruptly increasing acceleration could rip it apart though, but that's another story.
A bit of googling pulled up:
Meteorites: 10ish miles per second, depending (yukon = 9.3)
Earth through space: 18.5 miles per second
Sun through space: around 155 miles per second
This thing is moving really quite scarily fast. The energy in that thing must be huge, since it's already 3 times the size of the sun.
Questions: what would the effects of the speed be? Would the galaxial dust clouds be dense enough to 'fan the flames'? How does something that gets accelerated to that speed stay together - or, how big was it before it shed all the mass that couldn't stay together!
There was a monty python song about this... *hums*
Browsing with +2 to insightful posts and a higher threshold makes the average post seen seem a lot more ingenious
They aren't torn apart for multiple reasons. One of them is that there is nothing for them to hit that will tear them apart. Going millions of mph is different in a vacuum than it is in the earth's atmosphere. To get more complex, to the star it's not moving, the rest of the galaxy is. To understand more of what I'm talking about read about the reference frame in any basics physics book.
c# - Wait, it's not pronounced coctothorpe?
I just wonder why the star and the planets are not torn apart by such huge speeds?
a) we're not sure it has planets.
b) it's not velocity that kills, it's acceleration.
c) this acceleration can only be explained by current theory if it was a gravitational acceleration.
d) gravitational acceleration acts on all elements of an object equally, meaning that there was no force from the acceleration itself acting to tear the object apart. Just like when you're in freefall, you don't feel gravity acting on you.
Now TIDAL gravity can tear objects apart, but since the gravitationally assisted acceleration likely happened in the galactic core, the tides were probably pretty gentle... the tidal force at a black hole's horizon can be expressed as a function of mass over surface area; the bigger the hole, the less the tides.
I am disrespectful to dirt! Can you see that I am serious?!
Plugging 670*10^3m/s into Lorent'z equation:
t = t'/(sqrt(1-(v^2/c2))
where v=6.7*10^5m/s
and c = 2.99*10^8,
I got a time dilation of factor of 1.00000249. That is, time in the moving system (the star) will be observed by a stationary observer to be running slower by a factor of 1.00000249.
Not as impressive as I hoped it would be when I started the calculations.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
Goddamned Puppeteers. Before you know it, they'll be fleeing with all the good stars.
I guess someone finally found a really long plank and a place to stand.
...only 0.2% c
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The ergosphere around a black hole is full of matter that's orbiting the black hole at a speed that's not enough to get back out again - as a fast body comes through, it slingshots through the buzz of energy provided and comes out faster than it went in. This is above the point of no return, but there's still a lot of energy flying around there.
Browsing with +2 to insightful posts and a higher threshold makes the average post seen seem a lot more ingenious
Is there *really* a difference, physically, on an object moving at 1.5MM mph and one standing completely still, if they're not interacting with anything else? No. Their inertias are the same, so their physical properties and interactions are the same.
Momentum, however, could be a bitch. Imagine this star slamming into another star (or, a la the Death Star, a small planet in the Aldeberan system). Ka-pow, with the graphic like on the old Batman series! Would make Levy-Shoemaker look like a BB gun (you're gonna put your eye out!)...
Recently I saw on Discovery that many galaxies (if not all) were orbiting around supermassive black holes. And that the orbiting speed of the stars is proportional to the black holes' mass. This is known as the "M-sigma" relation.
This meant that the supermassive black holes actually contributed to the process of galaxy formation.
The theory is more or less the following:
In the center of a galaxy-sized gas cloud, a star collapsed, forming a black hole. The black hole began eating the gas around it, forming a quasar (quasars are the matter just about to be swallowed by a black hole, disintegrating and generating enormous amounts of energy).
The quasar, due to its high temperature and rotational speed, heated the surrounding gas cloud, activating a chain reaction that gave birth to all the stars in the new-forming galaxy.
Eventually, the quasar pushed away the stars, so the black hole could only be fed by the quasar itself. After that, the black hole enters a dormant phase (it has nothing else to eat), and the galaxy is already formed (of course, I'm talking about a process that takes billions of years).
I don't actually know how they measured it (and I'm not an astrophysicist and don't offer this as opinion, let alone fact) but 1.5 million miles per hour probably creates a significant doppler shift. The spectra of stars shows distinct bands that correspond with the absorption of photons at specific wavelengths. The reason the absorption is at specific, discrete wavelengths is that electrons in specific elements (e.g. Hydrogen, Helium, etc) absorb at specific wavelengths. The distance between absorption lines for different elements is fixed. For example, say Helium absorbs at some wavelength x and Hydrogen at some wavelength y. The difference between x and y is a constant (even under a doppler shift). So, if you see two absorption lines and they are x - y apart then one is the Hydrogen and one the Helium. This is overly simplified but the principle is the same (it just involves more than two lines). You can then tell how much doppler shift because you know what wavelength they should appear at and see what wavelength they actually appear at. Doppler shift is directly proportional to speed (I hope that's accurate). So, knowing the doppler shift you know the speed relative to the point of observation. Presumably you can work out the speed of the earth relative to some object by measuring the relationship between doppler shift from that body and the doppler shift from various other celestial bodies. Or, maybe they had a very long tape measure, a very powerful radar, or a very powerful laser or just guessed ;-)
Peace
simply owing to the earth's rotation, you are, at this moment, moving at a rate of approximately 1000 mph? Probably less since you are probably not at the equator.
Also, Due to the earth's orbit around the sun, were are traveling at approximately 67000mph.
According to findings of COBE, our galaxy is traveling at 300 k/s or about 1.34 million mph.
Why aren't you torn apart?
Can a star be /.'d? If so, did we just change the orbit of 5 other planets?
20s across Earth
2 days for the distance between Sun and Earth
1800 years to move between Solar System and Proxima Centauri
43 million years to cross the Galaxy.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
...just thinking about the kinetic energy that thing must be carrying with it makes my head spin.
All we need now is a super-massive baseball mitt on the end of a hyper-massive wooden pole hooked up to a mega-massive generator spindle.
The gift of death metal does not smile on the good looking.
I thought last year they found four "drawf" galaxies in vicinity of the Milky Way, about to be absorbed.
The big Kahuna of course will be the merger with Andromeda about two billion years hence. Our mutual gravitational attraction is drawing us together. In practical terms, both galaxies are essentially empty space. However Andromeda will grow from its present size in the sky of six full moons (192 arc minutes; but just a faint smudge) to fill the entire sky. See the collision simulation here.
Who wants to be the first to claim this is simply a huge plasma burst fired by an even larger weapon? Maybe it's just some alien race out there who wants to illustrate that they too, emjoy blowing things up with oversized guns. ^_^
Read: Rabbit Rue - Free serial nove
No
Or does it just mean the stars mass is greater than it was before..?
Yes, but only very slightly... since it's traveling at about 1/500th the speed of light, it did gain some mass, but very, very little relative to its original mass
If its neither of these, why has the star suddenly broken away from the galaxy
It all has to do with the angle and distance at which the star approached the black hole.
If it passes by a long distance away or at a slow speed (I don't know the equation to show you the threshold of speed/distance/mass), the chance is that it will enter some form of orbit, if irregular.
If it is nearly tangent to the object (but doesn't strike it), and it is already moving at a high enough velocity, then it will use the black hole as a slingshot and will gain velocity. You can check out the Cassini satellite's mission trajectory to see how it used Venus and Earth to gain velocity (relative to the sun)
"Fore!"
+1 Insightful, -1 Troll. What can I say, I'm an Insightful Troll.
No wonder they couldn't find the star in the Jedi archives
Philip
Signatures are broken
That's not entirely true. The force excerted by gravity goes as 1/r^2, where r is the distance between both masses.
If you have for example two large m1 and m2 each attached one end of a very long pole in a gravitational field caused by another mass M, the mass nearest to the M would experience a slightly stronger force than the other one. So that could, in theory, break the pole.
What you're talking about is tidal gravity. And tidal gravity is exactly what caused one star of a companion to be accelerated away while the other one was captured into an orbit.
On the scale of the objects themselves, though, the tides were probably extremely gentle. AFAIK companion stars are generally light-months apart. Even if this star was a planetary system, it's nearest planets are probably only a few light-minutes away...
I am disrespectful to dirt! Can you see that I am serious?!
I found more info on this, including more numbers, from this Reuters article. And by the way, it's moving at about 0.002c, which is pretty fast for something so huge. However, if you really want to be impressed, the gas in blazar jets moves at about 0.999c.
For those, who didnit get it.
Puppeteers are alien race from novel "Ringworld" by Larry Nivel. They were moving their home star system to a new galaxy to escape from the Core explosion.
The speed of light (c) is 300 000 km/s. 670/300000 = 0.0022. It's going at 0.0022c.
Don't worry, you're the not the first person to post disinformation on this site and get modded up as informative. Also, you should have worked with the metric values instead of messing around with the imperial values. Ye olde english system is great for measuring stuff in your trousers, but not as great for astrophysics.
I thought it was well established that at the center of the galaxy there is a planet, that God is on that planet, and that (as it is becoming abundantly clear), he needs a fucking starship!
In Repressive Burma, it's not just your connection that dies. slashdot.org/comments.pl?sid=314547&cid=20819199
From the SDSS J090745.0+24507 Daily News:
Cheers
-b
If I wanted a sig I would have filled in that stupid box.
the black hole presumed to be at the center of our galaxy has probably swallowed a huge amount of stars by now, so its gravity pull will be MUCH larger then even the largest know starts. as for the slingshot effect. as something small(er) gets pulled toward something heavy its increasing speed all the time. by the time the small object has reached the heavyer object and is about to do a orbit like turn its speed has become so great that it shots away from the heavy object at great speed because of the centrifugal force. they use the same techniek to give space probes some extra speed inside our solar system, aspecialy if they are going for the planets on the outside of our system.
All of the real astronomers are busy right now. Press 1 to be connected to a geek instead or 2 to leave a message.
-1-
Thank you.
The answer is : Black holes can be compilations of many stars. The one at the center of our galaxy that they are talking about is currently believed to be 3.7 million times the mass of our Sun (give or take 1.5 million).
This is just like we slingshot space probes past planets to get a gravitational speed boost, this star got pulled in towards the black hole but barely missed and got a the mother of all gravitational slingshots. I would guess that the fact that it had a companion was unimportant, and could have happened if it had been it had been a single star on the right trajectory.
IANAA.
And as you tread the halls of sanity, You feel so glad to be, Unable to go beyond. I have a message, From another time..
It sounds like Frederik Pohl's The World at the End of Time.
Why does it always have to be America? Can't it hate the French like everyone else?
And that kids is how I met your mother.
It doesn't, but the black hole is very massive - considerably more massive than any star in the galaxy.
And why would a great force at the centre of the galaxy be inclined to spit out stars at huge velocities?
It's tricky to explain and not terribly easy to get your head around, but I think the principle is similar to this demonstration (check out the video). The grav. potential energy of the companion star due to its attraction to the black hole is transferred into kinetic energy in the ejected star.
IANAPyet so please correct me if I'm wrong.
"Studies have shown that people who eat peanuts live longer than those who do not eat."
Longer answer: "The catch" is the catching. Imagine 'skitching' on a bullet train...
- Get maximum benefit by standing still, but suffer maximum acceleration. You'd need a HUGE shock chord.
- Get minimum accerelation by matching the speed, minimize the shock, but it costs you more energy to match the speed at an acceptable velocity difference.
I know yer asking about "the gravity of the asteroid", but most asteroids gravity is so low that you would have to be nearly their speed to even get a boost.*** IF *** we had a tractor beam that we could feather in the attractive, it would work. But then, we could just aim it at Mars, wait 23 minutes and HANG ON! We could also 'lasso the moon' at moonset and paraglide up into space.
And leave "intergalactic planetary" to the Beastie Boys. At that rate, the outcast star will still take a BILLIONish Years to get to Andromeda.
-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
"The laws of orbital mechanics are as unforgiving as the laws of Supply-Side Ecomnomics"
Comment removed based on user account deletion
If the approach wasn't that close, then the planets would still have been a lot more attracted to the "traveling star" than anything else. Their orbits may have been altered slightly by the influence of the larger mass, but they would have stayed.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
Even more if you stand up and hold out your arms! (But they probably have a sign up to keep your arms and legs inside your reference frame at all times.)
One line blog. I hear that they're called Twitters now.
How do we know that the star is being ejected from the solar system? According to relativity, to an observer in the galaxy, a star being ejected from the galaxy looks the exactly the same as using the star as the frame of reference and the whole of the milky way galaxy is moving away from it. Since we didn't actually see where this star was coming from, the star could have been holding still for a long time while the galaxy far,far away came stampeding past like the wildebeast stampede in Lion King. To us stuck here on earth it would look exactly the same either way. So its not so much tht the star is being ejected, but that it survived the stampede.
Your friend and well-wisher
m0smithslash
http://www.ferociousflirting.com
Another disgruntled Kerry supporter. Going to Canada is understandable, but leaving the galaxy?
Must have found about Bush's re-election.
I think the correct verb is "slingshat".
Bruce
1.5 million miles per hour is only 671,000 meters/second, or 0.00224 the speed of light. Relativistic effects are basically negligible.
While witty, that scenario doesn't hold up if you consider that either the star or the galaxy had to undergo a (relatively) brief period of acceleration in order to exhibit the behavior we currently see. The probability of every star in the galaxy except this one undergoing that kind of acceleration is minuscule - however, the probability of one star meeting the conditions of the proposed hypothesis is quite high.
That's how we solve these kinds of paradox problems in relativity. The classic "Twin Paradox" is solved in a similar manner. For those who need a refresher, it is the 'paradox' whereby one twin takes a trip at some substantial fraction of the speed of light and returns to find the other several decades older than himself (or herself) due to the time dilation effects encountered during the trip. The paradox is: From the point of view of the twin on the trip, it is the twin on Earth and everything else that ends up going very fast. Why shouldn't they be the ones to experience time dilation? The answer is, a deliberate acceleration is applied to the twin on the spaceship (reaction mass burning, converting energy to momentum). This defines the reference frame for the experiment, resulting in the correct application of the time dilation effect.
For our wayward star, its reference frame was defined by its proximity to our galactic center, and the probability that a super-massive black hole smacked it out of the galaxy's gravitational hole.
This sig is a test. If this had been an actual sig, you would be reading something quite a bit wittier than this now.
It is travelling at twice the speed needed to escape the gravitational clutches of the galaxy. About 80 million or 100 million years from now, Brown said, the star will exit the galaxy and become a lone wanderer of intergalactic space.
Yes, but that would make you a jerk, so the poster is correct!
Seriously though, what kills you is the difference in acceleration of the top and bottom - which is what the previous person said.
while (sig==sig) sig=!sig;
Its more like a satelite performing a rocket burn near the sun in order to gain velocity. Because the exhaust comes out moving more slowly (relative the the far away observer) than it would if the satellite was in higher orbit, the satelite gets much more boost.
In the case of a binary system and the black hole, I expcect what happens is the tidal forces break appart the binary system. The component that was travelling in the direction of motion (relative to the black hole) gets ejected with increased velocity while the unfortunate companion gets swallowed up - or goes into a much tighter orbit.
I wonder how much boost you get from the black hole at the centre of our galaxy as a result of frame dragging? Does frame dragging in fact produce a boost? (I would expect so) Do we have any estimates of the effect for the galactic centre?
Squirrel!
'cause black holes don't have a size limit.
Do you mean that they don't have a mass limit? Because they definitely have a size limit. They're 0-dimensional.
Or are you thinking of the Schwarzschild radius?
It's not offtopic, dumbass. It's orthogonal.
1: the problem with hitching a ride on a passing asteroid is that you need to match speed with it if you want to survive the landing. And if you can match its speed then you don't need its help any more, because that takes the same amount of energy as just going there yourself without the asteroid.
Maybe you could use enourmous bungee cords and rocket-propelled grappling hooks to latch on more gently, but if something snaps halfway through the process you'll be flung at high speed in entirely the wrong direction, probably without enough fuel to get back.
2: 1.5Mkps is fast in local terms, but for interstellar travel it's still a piddly 0.2% of c. That's thousands of years to get to the closest (planetless) stars, or billions of years for intergalactic.
To be blunt, human interstellar travel isn't going to happen, not by this or any other method, except a handful of probes. But absolutely nothing even remotely resembling Star Trek.
A little know intergalatic terrorist organization has claimed responsibility for the plasma burst observed. Secretary of State Rice could not be reached for comment. However, President Bush is ramping up space exploration with the intention of invading the terrorists home system.
Someone went and taunted the happy fun ball.
It's not offtopic, dumbass. It's orthogonal.
Or it's evidence of the opposite, that galaxies are not coalescing, but expanding.
G'nok: "Dammit, G'nariak -- I told you to calibrate the Star Destructor targeting computers yesterday!"
G'nariak: "Sorry, sir. I had to take the wife to her obstetrician yesterday during lunch; I was in a rush; it won't happen again."
G'nok: "Damned right it won't. The Earthlings SAW the Star Destructor test! They were supposed to EXPERIENCE the test!"
G'nariak: "Again, sorry sir -- I'll make it up to you."
G'nok: "You damn well will -- we have to explain to G'tariak why his vacation home at the edge of the galaxy isn't there anymore. Dumbass!"
IronChefMorimoto
just to add, kelvin is based on absolute 0.
0 degrees celsius is defined the temperature water turns into its solid state, 100 degrees celsius is defined as the temperature water turns boils at sea level.
farenheit is scaled off the temperature mercury turns to its solid state.
a 1 degree increase in celsius matches a 1 "degree" increase of kelvin, farenheit is all screwed up in how it scales (blame the english).
0 degrees kelvin == -273 celsius == -459 farenheit
The bad news is it's heading straight for us.
Intolerance for ambiguity is the mark of the authoritarian personality.
... that's the name of the black hole in the center of our galaxy, milky way. At least according to Perry Rhodan.
As for his body being accelerated and his blood isn't... That's only the case in as much as right now your body is trying to accelerate at 9.8 m/s/s toward the center of the earth. Your bone structure and muscles lets you resist it. Your blood is also trying to accelerate towards the center of the earth at the same rate. Your arteries and veins and your heart let you resist that as well.
Your body and blood aren't accelerating at different rates. They both deal with the same acceleration in the same way, with it acting as 'weight'. The problem with weight/acceleration is that your body was designed to handle only so much of it.
Now let's kick it up a notch. blood pooling...
Imagine a test pilot in a centrafuge machine. It takes him up to 6 G's and holds him there for an hour. Just like he was on a planet with 6x earth's gravity.
His body is accelerating at 6 G's. ;)
His blood is also accelerating at 6 G's (otherwise it would all leak out the back of his chair and that would be a 'bad thing'
His blood resists accelerating as you say, but so does his body (Bodies at rest tend to stay at rest tend to stay at rest, bodies in motion tend to stay in motion and all that). Nevertheless, the back of his chair is causing the lot of them to accellerate at 6 G's.
His heart, however is now trying to pump blood that 'weighs' 6x as much. The heart can't pump the heavier blood as easily or 'high' (relatively) as it could normally. His veins can't constrict as much as they normally would to force blood back into the right areas of the body, because the blood is pushing against them with much greater force. The veins also have valves to prevent blood from flowing back the wrong way, but these may give way under the additional pressure.
The blood is not accelerating at a different rate from the body, it's still in his veins and artieris, and so still in his body. His body is being accellerating at 6 G's and the blood, being trapped inside, is going along for the ride. But it acts as a much heavier fluid. So it starts to pool in the lower extremeties since it can't be pumped efficiently. Depending on how strong his heart is (and resilient his veins are), he might be able to handle 6 G's for a good long while. But if they aren't in quite as good of shape he might not be able to pump the blood well enough and might black out after a few seconds or minutes.
Once again the blood isn't accelerating at a different rate than the body (both are resisting being accelerated), anymore than your blood and body accelerate at different speeds on earth, it just has a higher 'weight' then the body was structurally designed to pump.
The next stage is to crank up the centrifuge chair/other-planet to 1000g's density. 1000 G's. Now the test pilot's ribs are trying to hold up themselves and the muscles etc attached to them. But they weight 1000x as much. The bones werent' constructed to hold such a high weight, so they snap. The 'body' isn't accelerating at a different rate than the... 'body', but it breaks down because it wasn't designed for such mechanical forces. Everything is being accelerated (and trying to resist it). Everything is accelerating at the same rate. It just can't handle the rate.
SDSS J090745.0+24507 will escape the galaxy; will it also escape our Local Group of galaxies?
Further, the Local Group of galaxies is moving at about 600 km/s (relative to the cosmic microwave background) in the direction of the Hydra-Centaurus supercluster.
Will SDSS J090745.0+24507 end up there?
Well they say its trajectory is coming pretty much directly from the centre of our galaxy, which supports their galactic black hole slingshot theory.
It's still possible that it's an extra-galactic object that just happened to intersect with the centre, but that requires us to assume a large coincidence, and we know what Occam has to say about that.
"Mind, as manifested by the capacity to make choices, is to some extent present in every electron." -Freeman Dyson
But, I know what you're saying. It's not bullshit. But there are some misnomers and misconceptions. I will try to expound on what I know you are saying.
- In general we are talking about a probe escaping Earth. Say, off to Saturn...
- After that, we are escaping the sun, as in Pioneer and V'Ger (before the upgrade
;-). In those cases, maximum velocity for minimum propellant is the goal.
- Orbits whose ellipses are the same major axis have equal period.
- High eccentricity orbits reach out farther than circular orbits of same major axis/period
- High eccentricity orbits require higher velocity near the planet/sun
- Until you hit escape velocity (a parabola or hyperbola) you are in a long ellipse
If you want to get a probe "out there" you want to burn at periapsis (Earth: perigee or Sun:perihelion). That leaves the peri at the same point and raises the other end. Do that enough times and you get escape on the last pass. Delta-V at any other point on the orbit will raise the peri and lower the apogee/aphelion. Propellant wasted.Often, satellites will burn at perigee, orbit around and repeat. This allows the same amount of propellant to get your there, but without the mass of a larger engine/structure. Smaller motor more often is more efficient, just takes longer. Nothing is free.
In short, you don't get more Delta-V, but you get it where you want it.
--
"Illustrative Myth: Once you are out of earth orbit, you are halfway to anywhere."
I guess I spend more time infront of the tube than you :P