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Study Details What Happens When Galaxies Collide

Posted by samzenpus on from the it's-full-of-stars dept.

Aspiring Astronomer writes: According to a recent study, when two galaxies of a similar mass collide, both galaxies will begin producing more stars. However, when one galaxy considerably outweighs the other, the larger galaxy begins producing more stars, whereas the smaller galaxy's star production begins to slow. This may be because the larger galaxy is able to draw gases from the smaller one, resulting in the formation of more stars. The Milky Way may experience a collision of it's own, because the Andromeda Galaxy is moving towards us at speeds upwards of 200,000 miles per hour. No need to worry, though; this collision is a few billion years away.

31 of 52 comments (clear)

  1. when worlds collide. by turkeydance · · Score: 1

    galaxies. i meant galaxies.

    1. Re:when worlds collide. by davester666 · · Score: 1

      fuck it. everything is going to hell. I'm going to remove the catalytic converter's from my truck.

      --
      Sleep your way to a whiter smile...date a dentist!
  2. Where baby stars come from. by sharkbiter · · Score: 4, Funny

    When a papa galaxy and a mama galaxy love each other very much...

  3. Gurren Lagann by Calsar · · Score: 1

    Thanks to Gurren Lagann we already know:
    http://i.kinja-img.com/gawker-...

    They also make effective melee weapons.

  4. Still a long ways off. by Anon-Admin · · Score: 1

    Maybe it would be better to leave a note for our Great^166,666,666 grand kids and give them a heads up.

    1. Re:Still a long ways off. by ClickOnThis · · Score: 1

      The summary says that the Andromeda Galaxy is moving towards us (and not us towards it), so we can sue the andromedans for any damage.

      You fail at relativity.

      --
      If it weren't for deadlines, nothing would be late.
    2. Re:Still a long ways off. by Anonymous Coward · · Score: 1

      You fail at humor

  5. Oh. Darn. by NoNonAlphaCharsHere · · Score: 3, Funny

    I assumed this was a video of Samsung phones being fired at each other.

  6. On behalf of the rest of the world by Swampash · · Score: 3, Funny

    What is a "mile"?

    1. Re:On behalf of the rest of the world by Anonymous Coward · · Score: 1

      When you convert to kilometers, things speed up.

      Best not to hasten our own doom.

    2. Re:On behalf of the rest of the world by Tomahawk · · Score: 1

      Approx. 1.6094 km. Give or take a few cm.
      For smaller distances/speeds, you can use eight fifths - this is what we always did.
      For larger distances/speeds, you can just ask Google. (or wolframalpha)

      https://www.google.co.uk/webhp...
      321869 km/h

      But, yeah, miles. Sheesh. Come on, USA - even Canada now uses km/h (since 1977). It's really just you and the Brits (didn't the USA, like, split from the Brits some years ago?)

    3. Re:On behalf of the rest of the world by wonkey_monkey · · Score: 1

      even Canada now uses km/h (since 1977)

      Kilometres per hour? Luddites. They should be using kilometres per kilosecond.

      --
      systemd is Roko's Basilisk.
    4. Re:On behalf of the rest of the world by michelcolman · · Score: 2

      OK, so it's just over five kilofeet then? Why don't they just say that?

    5. Re:On behalf of the rest of the world by g5g5g5 · · Score: 1

      Wouldn't it be easier if we all used FFF?
      https://en.wikipedia.org/wiki/FFF_system

  7. Andromeda has A TRILLION STARS by yo303 · · Score: 2

    Our galaxy has only a hundred billion. Knowing us we will go to war long before we collide, though.

    PREPARE FOR WAR AGAINST THE ANDROMEDA GALAXY!

    1. Re:Andromeda has A TRILLION STARS by swilly · · Score: 2

      The Milky Way is estimated to have 200 to 400 billion stars. However, just counting stars doesn't tell the whole story. The total mass of Andromeda is estimated at 1.5 x 10^12 solar masses, which is roughly double the 8.5 x 10^11 solar masses estimated for the Milky Way. Still pretty big, but not the 10x you are suggesting.

      Of course, that is our best information at present. Historically, estimates have varied quite a bit. Back in 2006 there were a bunch of news articles stating that the Milky Way had fewer stars but more mass from dark matter. And then Andromeda was determined to be four times more massive. And now it's only twice as massive. I expect this to be significantly revised as we learn more about both galaxies (especially our own: it's harder to learn size, shape, and mass from inside than it is from outside) and as we learn more about dark matter.

  8. "Study Details What Happens When Galaxies Collide" by Narcocide · · Score: 1

    I'm pretty sure Powerman 5000 already covered this.

  9. Never Tear Us Apart by jblues · · Score: 1

    Wasn't this already covered in the INXS song from the 80s? Don't ask me, what you know is true. When two worlds collide, 8 bit synthesizers start playing.

    --
    If it acquires resources on instantiation like a duck, then its a shared_ptr<Duck>
  10. Almost there... by Alwin+Henseler · · Score: 3, Insightful

    Just a few words shorter, and even /. users may read the article.

    Btw. since galaxies are mostly empty space, "to collide" doesn't sound right, imho. Two galaxies "mingling" might be a better description. A star from galaxy A here, a star from galaxy B there, a cloud from galaxy A over here, a few 'minor' collisions here & there, etc. Kind of like how 2 clouds of powder would 'collide'. And of course taking place over a long time span.

    1. Re:Almost there... by ganjadude · · Score: 1

      galactic orgy?

      --
      have you seen my sig? there are many others like it but none that are the same
    2. Re:Almost there... by dryeo · · Score: 1

      Not really empty space, something like 2 atoms per cc, which is enough that the gas compresses and triggers lots of star formation. From outside would look pretty spectacular, from inside, lots of radiation from all the new blue stars and supernova and likely sterilization of any inhabited planets.

      --
      https://en.wikipedia.org/wiki/Inverted_totalitarianism
    3. Re:Almost there... by behrooz0az · · Score: 2

      Didn't you read the GP? no touching

      --
      Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion. -- Spazmania (174582)
    4. Re:Almost there... by michelcolman · · Score: 2

      But once they "collide" (mingle), how can you still say that one galaxy is producing more stars than the other? I mean, doesn't it just become one big mess?

  11. Re:Press releases by wonkey_monkey · · Score: 1

    Stellar production rates change == "what happens"

    --
    systemd is Roko's Basilisk.
  12. Re:spectrum by michelcolman · · Score: 3, Informative

    Yes, that galaxy is indeed blueshifted. Who told you that "all the stars" are redshifted? When you look at the night sky, you'll see about the same number of blueshifted as redshifted stars, since the vast majority of them are in our own galaxy and we're all just revolving around the center. And the galaxies in our immediate vicinity are kind of clumping together, not expanding. When you look at objects outside our local cluster of galaxies, yes, those do all appear redshifted. The further they are, the more redshifted they appear. And that indeeds indicates that the universe is expanding. But in our local neighbourhood, there's plenty of blueshifted stuff.

  13. What!? An Astronomy post not pitched in Medium? by tommeke100 · · Score: 1

    I refuse to read the linked article unless it is spoon-fed to me through a nice layout and beautiful pictures and animations in an easy to digest scroll-down fashion!

  14. BTW, the arms support electric currents by paradigmsareconstruc · · Score: 1
    There's a potential clue as to why in this article ...

    http://phys.org/news/2015-06-m...

    "Spiral arms can hardly be formed by gravitational forces alone," Beck said. "This new IC 342 image indicates that magnetic fields also play an important role in forming spiral arms."

    The new observations provided clues to another aspect of the galaxy, a bright central region that may host a black hole and also is prolifically producing new stars. To maintain the high rate of star production requires a steady inflow of gas from the galaxy's outer regions into its center.

    "The magnetic field lines at the inner part of the galaxy point toward the galaxy's center, and would support an inward flow of gas," Beck said.

    It seems apparent that what they're getting at is that the spiral arms are associated with electric currents which create the magnetic fields. Either way, a charge imbalance would be an easy route towards an explanation of this observation.

  15. Earths sky will have half dozen milky way streaks by peter303 · · Score: 1

    During the collision era from simulations I've seen. However in two gigayears the planet will be too hot for life. In a few hundred million years the atmosphere will have too little carbon dioxide to support photosynthesis multi-cellular life. Existing carbon is gradually sucked into limestone formation. Earth will revert to a bacteria planet unless there is teraforming (burning the limestone to release CO2).

  16. Pronoun Trouble by almitydave · · Score: 1

    Come on, people.

    POSSESSIVE: my, your, his/her/its, our, your, their
    CONTRACTIONS: I'm, you're, he's/she's/it's, we're, you're, they're

    Put a sticky note on your monitor, tattoo this on the back of your hand, whatever it takes...

    --
    my, your, his/her/its, our, your, their
    I'm, you're, he's/she's/it's, we're, you're, they're
  17. Rare occurrence by OhSoLaMeow · · Score: 1

    Should be a pretty rare occurrence. They haven't made Galaxies for over 40 years.

    --
    They can take my LifeAlert pendant when they pry it from my cold dead fingers.
  18. Re:spectrum by michelcolman · · Score: 1

    Yes, I know who Hubble is. And Hubble's law says that, for objects observed in deep space (more than 10 megaparsecs away), doppler-shift-measured velocity is approximately proportional to their distance to earth. It does not apply to our local neighbourhood.