Supermassive Black Holes Keep Galaxies From Getting Bigger

It’s long been a mystery for astronomers: why aren’t galaxies bigger? What regulates their rates of star formation and keeps them from just becoming even more chock-full-of-stars than they already are? Now, using a worldwide network of radio telescopes, researchers have observed one of the processes that was on the short list of suspects: one supermassive black hole’s jets are plowing huge amounts of potential star-stuff clear out of its galaxy.

Astronomers have theorized that many galaxies should be more massive and have more stars than is actually the case. Scientists proposed two major mechanisms that would slow or halt the process of mass growth and star formation — violent stellar winds from bursts of star formation and pushback from the jets powered by the galaxy’s central, supermassive black hole.

Read more: Our Galaxy’s Supermassive Black Hole is a Sloppy Eater

“With the finely-detailed images provided by an intercontinental combination of radio telescopes, we have been able to see massive clumps of cold gas being pushed away from the galaxy’s center by the black-hole-powered jets,” said Raffaella Morganti, of the Netherlands Institute for Radio Astronomy and the University of Groningen.

The scientists studied a galaxy called 4C12.50, nearly 1.5 billion light-years from Earth. They chose this galaxy because it is at a stage where the black-hole “engine” that produces the jets is just turning on. As the black hole, a concentration of mass so dense that not even light can escape, pulls material toward it, the material forms a swirling disk surrounding the black hole. Processes in the disk tap the tremendous gravitational energy of the black hole to propel material outward from the poles of the disk.

NGC 253, aka the Sculptor Galaxy, is also blowing out gas but as the result of star formation (Image: T.A. Rector/University of Alaska Anchorage, T. Abbott and NOAO/AURA/NSF)
NGC 253, aka the Sculptor Galaxy, is also blowing out gas but as the result of star formation (Image: T.A. Rector/University of Alaska Anchorage, T. Abbott and NOAO/AURA/NSF)

At the ends of both jets, the researchers found clumps of hydrogen gas moving outward from the galaxy at 1,000 kilometers per second. One of the clouds has much as 16,000 times the mass of the Sun, while the other contains 140,000 times the mass of the Sun.

The larger cloud, the scientists said, is roughly 160 by 190 light-years in size.

“This is the most definitive evidence yet for an interaction between the swift-moving jet of such a galaxy and a dense interstellar gas cloud,” Morganti said. “We believe we are seeing in action the process by which an active, central engine can remove gas — the raw material for star formation — from a young galaxy,” she added.

The researchers published their findings in the September 6 issue of the journal Science.

Source: NRAO press release

6 Replies to “Supermassive Black Holes Keep Galaxies From Getting Bigger”

  1. How can something get out of a blackhole when “Even light cannot escape it”..Sorry for asking such a naive question but it has plagued my mind forever

    1. The matter/energy that black holes shoot out isn’t stuff that’s passed across the event horizon, it’s stuff that’s been wrapped up and accelerated in the accretion disk and then flung out by its powerful spinning magnetic field lines. It’s like Cookie Monster… some of the cookie ends up in his mouth, but most gets spilled all over the floor.

      This is especially true for rotating supermassive black holes which have large accretion disks and complex magnetic fields. It’s a messy buffet.

  2. About
    posted by Brian speculating and described about another experiment but
    connected within:

    Nice
    experiments, but lack of correct ideas, which is understandable because
    obviously the author don’t familiar with the Undivided Structure of the Matter
    USM http://www.kanevuniverse.com Namely: The unity and essence of
    the fields (gravitational electrostatic-magnetic and nuclear ones), which is
    shown convincingly in USM. From this follows that all the fields are the same
    which appears in between nuclear space like a nuclear, in between atoms space
    like electrostatic and in between galaxy space like gravitational one. How is
    created and what is the essence of the magnetic field also is shown in very
    convincing way. Moreover in very important analysis is shown the inertial
    character of this unity field, which by one very simple way explain the
    expansion of the over space and its acceleration, which is not absolutely but
    only for us and only for our galaxy radius-position of our Sun. It is truth
    that the galaxies aren’t form their shape by the some black hole in the center or
    the so called dark energy indeed exist, but the galaxy gravitational field is
    creates through inter movement between the galaxies themselves how it is shown
    on USM. This defines the rotation centripetal forces of galaxy and forms its
    shape by analogy with the atoms quantum action, which is means that this forces
    attract only part of the galaxy matter, where are birth the stars little
    centrally area with the radius around (10 raise to the 12 power) times smaller than the present orbital radius
    of the Sun and only about the first moment of stars formation. The rest of the
    galaxy matter is disperses by inertial way. That is why the tangential velocity
    of the galaxy matter remains almost constant with galaxy radius increasing, but
    not because of the so called dark matter, which play little role of this
    velocity decreasing and therefore this mass is far more little than previously estimated.
    The plasma play little role in the galaxy live because of the same inertial
    character of the field and because the density of the galaxy looking from
    inside is very weak and the pressure respectively, but it is truth that in the
    stars that role is strong interaction. In USM is given very important
    explanation of the polarization of the space and connection between strong and
    weak interactions and many more…. It is seen Brian that the so called big bang
    in fact is far more different thing than nowadays imagination and of course
    there is no place about Higgs boson, but the found out particle exist (if it
    isn’t resonance only – that must to be proven through enough numbers of
    experiments farther) and it isn’t Higgs particle – such particle doesn’t exist.

    About the
    slowly changing patterns, it is means that the time in the over space flows so
    slowly that we cannot observe it, but such changing exist. That is why all the
    constants including masses of the particles for example, also is changing by
    the increasing of the orbital radius of the Sun on the galaxy, due the
    compressing of the subspace and expansion of the over space and many more….
    G.Kanev

  3. Never
    forget the definition of black hole according to general relativity and it is
    place in the space where nothing can escape and anything stream in! Sensible
    person immediately ask you..where all these come in like masses, energies and
    soon, and you cannot give him reasonable answer……

    What is the first: the revolving disc, which
    may hasn’t any mass, but which has tangential velocity and therefore bend the
    space around itself, or the spherical mass which has or hasn’t tangential
    velocity but we accuse that this mass bend the space and creates the so called
    space time curvilinear tensor?

    Gravity is
    dynamically characterization (centripetal acceleration) but the bending is
    kinematical characterization, so obviously You are wrong!

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