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Scientists Find Evidence of Black Holes Sucking

Posted by CmdrTaco on from the blinded-me-wtih-science dept.

Sawopox writes "A bunch of guys a lot smarter than I am managed to find evidence of matter being sucked into a blackhole at roughly 6.5 million mph. " Yeah, but what kinda mileage does that matter get?

5 of 161 comments (clear)

  1. Yeah, but what kinda mileage does that get? by anticypher · · Score: 3

    Doesn't matter, its all downhill.

    the AC

    --
    Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on
  2. Science reporting... by curril · · Score: 3
    I always hate getting science news from the regular press because they use hyperbole to describe scientifically precise terms.

    ...direct evidence for the first time of matter being pulled into a black hole.
    Accretion disks, almost by definition, are direct evidence of matter being sucked into a massive object, black hole, neutron star, white dwarf, etc. What the article doesn't say is that accretion disks are so hot and dusty that we haven't been able to see what's going on inside them. The finding of Doppler-shifted light allows us to determine, experimentally as opposed to theoretically, the speed of matter within the disk.

    ...extremely strong gravity sucks in everything, including light.
    Light is not "sucked" into a black hole. It is red-shifted by the gravitational field. Any light that crosses the event horizon is red-shifted to undetectablity by the time it leaves the gravitational field. Light can also be "bent" by going near the strong gravitational field.

    ...gravity is so strong that nothing, not even light, can escape
    Current theory allows for Hawking radiation to escape, at a rate inversely proportional to mass. Black holes of small mass should lose energy so quickly that they explode.

    ...a million to a billion suns compressed into a tiny region.
    The "tiny region" is relative. The more massive the black hole, the greater the radius of the event horizon, and the more even the gravitational gradient at the event horizon. It is possible that our entire universe is contained within the event horizon of a gigantic black hole. Current theory has difficulty explaining what happens to matter inside the event horizon. The density of matter inside a super-massive black hole would not have to be that great.

    ...light is stretched, or red-shifted, as it speeds away from the Earth
    Light is not red-shifted as it "speeds away from the Earth", except for a very minor gravitational effect. Red (or blue) shifting is due entirely to the relative velocities of the observers.

    ...the light seemed to be moving at a clip of about 6.5 million mph...
    Since the speed of light is constant, one must assume that they mean the red-shift from the light indicated that the matter was moving along at this speed relative to "stationary" gas of the disk.

    The only way scientists have been able to ``see'' them up to now is by looking at the accretion disks
    Or by observing the wobble of a star paired to a singularity. Other, so far unsuccessful, possibilities include observing gravitational lensing effects, and gravitons.

    "How old are you in light-years?" "Why, about 30 feet."
  3. Why is 6.5 Million MPH so impresive by quade]CnM[ · · Score: 5

    some quick calulations....


    6,500,000 MPH = 2,905,760 Meters/Sec = 2.9e6

    Speed of Light = 299,792,458 Meters/Sec = 3.0e8


    if you figure this out, you get the fact that it is only traveling at less then 1% the speed of light (the theoretical limit). now lets see how Relatively stacks up agenst say a 1 kg particle.


    m=mo/sqrt(1-(v^2)/(c^2))


    This brings the relative Mass to 1.000047 kg or a ~.005% diffrence in mass. No big deal... Havent they goten particals up to 10% the speed of light before in mass accelerators.

    1. Re: Why is 6.5 Million MPH so impresive by rw2 · · Score: 3
      Re: the subject.

      Because that speed is very different than the speed of the surrounding area and, since gravity falls off so quickly with distance, (Newton is sufficient here) the fact that the particles in question are moving so quickly is amazing.

      Re: No big deal... Havent they goten particals up to 10% the speed of light before in mass accelerators.

      I don't know the term mass accelerator, but if you mean particle accelerator then yes, they have gone faster than 10%. Much. The percentage of the speed isn't really important at the level of most detectors but it is more than 99.99%. What is measured is the energy of the accelerator, which for Fermilab is ~2TeV and in the future CERN will run at ~7TeV. See either site for great intros to high energy physics pages.

  4. Please.... by mrsam · · Score: 3
    matter being sucked into a blackhole at roughly 6.5 million mph.

    Please, let's not make any Monica Lewinsky jokes here, OK?
    --