Follow Slashdot stories on Twitter

 



Forgot your password?
typodupeerror
×
Space

Star Flung From Milky Way at High Speed 512

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."
This discussion has been archived. No new comments can be posted.

Star Flung From Milky Way at High Speed

Comments Filter:
  • That's Life (Score:5, Funny)

    by Doc Ruby ( 173196 ) on Wednesday February 09, 2005 @12:16PM (#11618694) Homepage Journal
    It's a glider [radicaleye.com]!
  • by lecithin ( 745575 ) * on Wednesday February 09, 2005 @12:16PM (#11618696)
    "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.
    • by lucabrasi999 ( 585141 ) on Wednesday February 09, 2005 @12:22PM (#11618760) Journal
      Instead they are going to call it a galaxy challenged star.

      The Mayor Star of the Milky Way decided to form a committee to review the causes of "Outcast Star Syndrome". That committee, which will be composed of various leaders in the Star Community, along with interested Asteroids, Planets and Comets, will interview other Stars that have, through no fault of their own, also been cast out of the galaxy.

      In six months, the Committee will issue a report that includes recommendations on how we can prevent Outcast Star Syndrome along with a 12 step program to re-integrate former Outcast Starts into the entire Milky Way community, with the hopes that they will become productive members of the community again.

  • by essreenim ( 647659 ) on Wednesday February 09, 2005 @12:17PM (#11618704)
    galactic pin ball here we come!!
  • Yep. (Score:3, Funny)

    by inertia187 ( 156602 ) * on Wednesday February 09, 2005 @12:18PM (#11618716) Homepage Journal
    Just like my screen saver predicted.
  • by falser ( 11170 ) on Wednesday February 09, 2005 @12:20PM (#11618736) Homepage
    Ok, now how do we apply this knowledge to do the same to Microsoft/Paris Hilton/Terrel Owens/Celine Dion.... ?
  • by FIGJAM ( 29275 ) on Wednesday February 09, 2005 @12:22PM (#11618763)
    Starlight, star bright, first-of-its-kind star I see tonight, I wish I may, I wish I might, get laid tonight.

  • Speed is relative (Score:4, Insightful)

    by Hoi Polloi ( 522990 ) on Wednesday February 09, 2005 @12:23PM (#11618768) Journal
    What are they measuring the star's speed against? The center of our galaxy? The earth?
  • Relative speeds (Score:3, Interesting)

    by FirienFirien ( 857374 ) on Wednesday February 09, 2005 @12:26PM (#11618818) Homepage
    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*
    • Re:Relative speeds (Score:4, Informative)

      by Spackler ( 223562 ) on Wednesday February 09, 2005 @02:12PM (#11620315) Journal
      You seem to be using "through space" as a non-relative term. If the sun is moving "through space" at 155 miles a second, how can earth be moving "through space" at only 18 miles a second. It that was the case we would be 16,000 miles farther from the sun since I started writing this email. 3 million miles more than when I woke up this morning and 180,795,888,000 miles since I was born.

  • by GillBates0 ( 664202 ) on Wednesday February 09, 2005 @12:29PM (#11618867) Homepage Journal
    That's 0.002 [google.com] times the speed of light or only about 1/500th the speed of light.

    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.

  • Hindmost (Score:5, Funny)

    by Rorschach1 ( 174480 ) on Wednesday February 09, 2005 @12:30PM (#11618868) Homepage
    Goddamned Puppeteers. Before you know it, they'll be fleeing with all the good stars.
  • Lever (Score:4, Funny)

    by suso ( 153703 ) on Wednesday February 09, 2005 @12:31PM (#11618888) Journal
    I guess someone finally found a really long plank and a place to stand.
  • Still... (Score:3, Informative)

    by SharpFang ( 651121 ) on Wednesday February 09, 2005 @12:31PM (#11618892) Homepage Journal
    ...only 0.2% c
  • The speed of light is 1.5 million miles an hour!
  • Inertia & Momentum (Score:5, Insightful)

    by mreed911 ( 794582 ) on Wednesday February 09, 2005 @12:34PM (#11618917)
    While this seems astounding, leaving some to wonder "how's a star stay together at 1.5MM mph?", it's important to remember that, for all intents and purposes, it's travelling through NOTHING, through a vacuum. As long as its velocity is stable (not running into things to slow it down), there's no inertia to change it's shape, etc.

    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!)...

    • by forand ( 530402 )
      You are missing the point. It is leaving the galaxy. Everything else we have seen in our Galaxy is gravitationally bound to it thus it cannot leave, this is amazing because it moving above the escape velocity of the galaxy.
    • 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 [amazon.com]. To u
      • 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.
  • ... for being the last one on the galactic ice-skating chain of kids^H^H^H^H stars.
  • by Spy der Mann ( 805235 ) <`moc.liamg' `ta' `todhsals.nnamredyps'> on Wednesday February 09, 2005 @12:38PM (#11618952) Homepage Journal
    Recently I saw on Discovery that many galaxies (if not all) were orbiting around supermassive black holes [berkeley.edu]. And that the orbiting speed of the stars is proportional [arxiv.org] 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).
    • by bigmaddog ( 184845 ) on Wednesday February 09, 2005 @01:30PM (#11619687)

      Call me a bitch about details, but... (I know, someone else will be a detail bitch about my details.)

      Quasars radiate tremendous amounts of energy not because matter "disintergrates" as it falls inwards but merely because it falls inwards.

      It's as if a bucket of bricks fell on your head from ten stories up (well, almost) - while up there, the bricks & bucket have potential gravitational energy. As the whole thing falls, gravitational potential energy is converted to kinetic energy, some of which is lost to friction with the surrounding air. It may generate sound, like a low whistle or thunderous roar, depending on the aerodynamic properties of the bucket. When the bucket hits, all the remaining kinetic energy is dissipated by your skull and brain, and "radiates away" as sounds and splattering gore. (This last part about the brain and plattering is not necessary for the analogy but I just like talking about gore.)

      So, same thing with quasars, more or less. Stuff far away from the quasar has a lot of gravitational potential energy because quasars are so damn massive, which leads to powerful gravity. As it falls inwards, it trades this energy for kinetic enrgy, moving faster, and, as it grinds against other stuff in the accretion disk around the quasar, some of which is moving slower, some of this energy is lost to friction, except instead of sound (whistling) with the bucket & bricks, you get EM radiation. (If the bucket fell from really high up, it might heat up from friction and start emmiting some radiation of its own, in infra red and then in visible light.)

      Sice the black holes at the centre of galaxies are so damn huge, and because falling into a black hole release several orders of magnitude more of the massenergy of a piece of matter than fission or fusion ever could (astronomy textbook not at hand, so can't quote the numbers), we get a whole lot of radiation this way, and so quasars are really really bright.

  • Does anyone know... (Score:3, Interesting)

    by midifarm ( 666278 ) on Wednesday February 09, 2005 @12:39PM (#11618976) Homepage
    if this thing is accelerating, decelerating or at a constant speed?

    Peace

    • by Overzeetop ( 214511 ) on Wednesday February 09, 2005 @01:02PM (#11619207) Journal
      Well, if we can simplify the motion to (1) the galactic core and (2) the star, Kepler's equations require that it be decelerating. Based on the fact that it has 2x the escape velocity of the galaxy, that would put it on a hyperbolic path with the galactic core at its focus (the real one). After an (infinite) period of time, it will slow to a spped which is 1.7x escape velocity (v-inf^2=v^2 - v-esc^2) based on the 2x number being the maximum velocity obtained. This is more commonly known as the "hyperbolic excess speed".

      This post brought to you in part by Bates, Mueller, and White...the best textbook value in the world ($6 for an astrodynamics text...and a pretty good on at that).
    • Theoretically, decellerating.

      Observationally, we don't know. It required a lot of observations to gauge its proper speed. It is going to require a lot more to gauge how much that speed is changing.

      One moment of insight I had into how much we don't know about our universe was fooling around with some software from NASA. (Perks of working in a science museum with a planetarium.) One of the items you could toggle on you flights around the solar system and surrounds and ... well just about anywhere in the o

  • Can a star be /.'d? If so, did we just change the orbit of 5 other planets?
  • /usr/dt/bin/xlock -mode galaxy

    There's your confirmation. At least on some Solaris servers I've seen.

  • At last.. Jesus is taking his ball.. AND GOING HOME!!

    repent!

  • Impressive? (Score:3, Interesting)

    by SharpFang ( 651121 ) on Wednesday February 09, 2005 @12:45PM (#11619038) Homepage Journal
    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.
  • Man... (Score:3, Funny)

    by Mindwarp ( 15738 ) on Wednesday February 09, 2005 @12:46PM (#11619048) Homepage Journal
    ...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.
  • This incredible speed likely resulted from a close encounter with the Milky Way's central black hole, which flung the star outward like a stone from a slingshot.

    Close enough to accelerate it that much, yet not disrupt it in the process through tidal effects? An interesting star, to say the least. Too bad we can't observe it more closely.

  • by peter303 ( 12292 ) on Wednesday February 09, 2005 @12:53PM (#11619118)
    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. [utoronto.ca]
  • by Trifthen ( 40989 ) on Wednesday February 09, 2005 @12:54PM (#11619123) Homepage
    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. ^_^
  • by fizban ( 58094 ) <fizban@umich.edu> on Wednesday February 09, 2005 @12:55PM (#11619130) Homepage
    "Fore!"
  • More info (Score:3, Interesting)

    by Woogiemonger ( 628172 ) on Wednesday February 09, 2005 @01:00PM (#11619192)
    I found more info on this, including more numbers, from this Reuters article [yahoo.com]. 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 [usatoday.com] moves at about 0.999c.
  • Black hole? (Score:5, Funny)

    by The One and Only ( 691315 ) <[ten.hclewlihp] [ta] [lihp]> on Wednesday February 09, 2005 @01:05PM (#11619249) Homepage
    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!
  • by account_deleted ( 4530225 ) on Wednesday February 09, 2005 @01:06PM (#11619261)
    Comment removed based on user account deletion
  • Looks like (Score:4, Funny)

    by Ohreally_factor ( 593551 ) on Wednesday February 09, 2005 @02:48PM (#11620780) Journal
    Someone went and taunted the happy fun ball.
  • Or.... (Score:3, Interesting)

    by fleener ( 140714 ) on Wednesday February 09, 2005 @02:52PM (#11620822)
    Or it's evidence of the opposite, that galaxies are not coalescing, but expanding.
  • by IronChefMorimoto ( 691038 ) on Wednesday February 09, 2005 @03:18PM (#11621116)
    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
  • by carcosa30 ( 235579 ) on Wednesday February 09, 2005 @04:00PM (#11621642)
    The bad news is it's heading straight for us.

So you think that money is the root of all evil. Have you ever asked what is the root of money? -- Ayn Rand

Working...