Galaxy Zoo Talk

No Black Hole

  • tony_cim by tony_cim

    Is it possible to have a object forming without a black hole which can resemble or have similar qualities to a galaxy.

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  • Budgieye by Budgieye moderator

    We need a scientist here, because this question is at the forefront of knowledge. I'll answer in the meantime, but I may be wrong. I think every galaxy starts out with a black hole, though after collision, some small galaxies may have lost theirs.

    Black holes are only a small part of a galaxy, and galaxies can survive without them.

    Some info

    https://en.wikipedia.org/wiki/Galaxy_formation_and_evolution

    Blog; AAS 218: Black Hole Growth and Host Galaxy Morphology June 8, 2011 by Kevin https://blog.galaxyzoo.org/2011/06/08/aas-218-black-hole-growth-and-host-galaxy-morphology/ pdf and quicktime video

    APOD website: Galaxy Evolution Tracking Animation gravity causes clumps of matter to form into galaxies which immediately begin falling toward each other https://apod.nasa.gov/apod/ap160530.html Video Credit: Donna Cox (AVL NCSA/U. Illinois) et al., NASA's GSFC, AVL, NCSA Explanation: How did the universe evolve from such a smooth beginning? To help understand, computational cosmologists and NASA produced the featured time-lapse animated video depicting a computer simulation of part of the universe. The 100-million light-year simulation starts about 20 million years after the Big Bang and runs until the present. After a smooth beginning, gravity causes clumps of matter to form into galaxies which immediately begin falling toward each other. Soon, many of them condense into long filaments while others violently merge into a huge and hot cluster of galaxies. Investigating of potential universe attributes in simulations like this have helped shape the engineering design the James Webb Space Telescope, currently scheduled for launch in late 2018.

    Here is a publication by one of the Zoo scientists

    Galaxy Zoo: bulgeless galaxies with growing black holes http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1207.4190

    Posted

  • vrooje by vrooje admin, scientist

    Yes, we think most galaxies have supermassive black holes, but not all. There are certainly some dwarf galaxies that show no evidence for having a black hole at their center (and others that do).

    However, deciding a galaxy has no black hole takes a lot of work and many follow-up observations. It's impossible to rule out the presence of a black hole just by looking at a GZ image. Black holes, even very massive ones, don't take up much space, so when we observe a galaxy in our surveys even a supermassive black hole in that galaxy takes up much, much less space than a single pixel - and there would be plenty of room in that pixel for stars and other bright things to mask the presence of a black hole in our observations.

    Hope that helps.

    Posted

  • Budgieye by Budgieye moderator

    Thank you for your reply, Dr Simmons.

    Posted