Merging Galaxies

[deapfreeze]

If galaxies merge to make a larger galaxy. What happens to the black holes at the center does the larger galaxies black hole swallow the smaller one up? Or do we get a galaxy with 2 black holes? <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[mytheory]

That's a really interesting question, it's one I have pondered over myself. I'm no astronomer but I would imagine that a galaxy with a bigger black hole would attract another with a smaller black hole. I strongly believe in my theory that black holes alter the shape and form of every galaxy that has one. I still believe that the more massive/ dense these holes are the more extreme the galaxies shape. For example the spiral shaped galaxies which appear to be swirling in one direction mite harbor the bigger black holes and because of this they are swallowing all stars and gas inside of them at a faster rate.&nbsp; <div class="Discussion_UserSignature"> <span style="font-weight:bold" class="Apple-style-span">@LEX</span> </div>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If galaxies merge to make a larger galaxy. What happens to the black holes at the center does the larger galaxies black hole swallow the smaller one up? Or do we get a galaxy with 2 black holes? <br /> Posted by deapfreeze</DIV></p><p>I think, for obvious reason, the larger black hole can't slowly accrete material from the smaller one so that's not an option.&nbsp; The other two options are a violent merger that releases an enormous amount of energy in the form of gravitational waves or that one of the black holes is ejected.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[deapfreeze]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I think, for obvious reason, the larger black hole can't slowly accrete material from the smaller one so that's not an option.&nbsp; The other two options are a violent merger that releases an enormous amount of energy in the form of gravitational waves or that one of the black holes is ejected.&nbsp; <br />Posted by derekmcd</DIV><br /><br />If one of the black holes were ejected would this not start a new galaxy as the ejected black hole starts to pull things towards it? <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If one of the black holes were ejected would this not start a new galaxy as the ejected black hole starts to pull things towards it? <br />Posted by deapfreeze</DIV><br /><br />Long time since we heard from you deapfreeeze!</p><p>&nbsp;</p><p>Probabaly not. Such ejections would take place at VERY high velocities. Manwhile the galaxies left behing not only have the mass of the black hole at the center, but the mass of all the stars in the galaxies to help hang on to everything. </p><p>Once the ejected black hole is in intergalactic space, theres such a low matter density, there's not much to grab on to.</p><p>MW</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[deapfreeze]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Long time since we heard from you deapfreeeze!&nbsp;Probabaly not. Such ejections would take place at VERY high velocities. Manwhile the galaxies left behing not only have the mass of the black hole at the center, but the mass of all the stars in the galaxies to help hang on to everything. Once the ejected black hole is in intergalactic space, theres such a low matter density, there's not much to grab on to.MW <br />Posted by MeteorWayne</DIV><br /><br />Hi MW... If the ejected black hole has a low matter density it should just evapourate? Or am I wrong with my thinking? <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hi MW... If the ejected black hole has a low matter density it should just evapourate? Or am I wrong with my thinking? <br />Posted by deapfreeze</DIV><br /><br />All black holes have the same matter density..."infinite" or more correctly, beyond our physics. Only very small (inches?) black holes can "theoretically" evaporate even in many many times the lifetime of the Universe.</p><p>I should point out that the Hawking radiation that can evaporate Black holes has not yet been observed, IIRC.</p><p>It's a fairly new concept that hasn't really had time to be thoroughly investigated yet.</p><p>Wayne</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[deapfreeze]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>All black holes have the same matter density..."infinite" or more correctly, beyond our physics. Only very small (inches?) black holes can "theoretically" evaporate even in many many times the lifetime of the Universe.I should point out that the Hawking radiation that can evaporate Black holes has not yet been observed, IIRC.It's a fairly new concept that hasn't really had time to be thoroughly investigated yet.Wayne <br />Posted by MeteorWayne</DIV><br /><br />So what we are looking at here would be a black hole without a galaxy just floating around space? I would have thought that after it was ejected it would either start pulling in more objects from the area it is in or just disappear. I just can't picture a black hole with nothing being pulled in or circling the event horizon. It just sounds strange to me... lol </p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>So what we are looking at here would be a black hole without a galaxy just floating around space? I would have thought that after it was ejected it would either start pulling in more objects from the area it is in or just disappear. I just can't picture a black hole with nothing being pulled in or circling the event horizon. It just sounds strange to me... lol &nbsp; <br />Posted by deapfreeze</DIV><br /><br />It may sound strange, but you are basically correct. Most space within a galaxy would qualify as a superb vaccuum here on earth....intergalactic space might only have a few "particles) per cubic cm.</p><p>Out there, there are no objects to pull in, and darn few atoms or molecules as well.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[deapfreeze]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It may sound strange, but you are basically correct. Most space within a galaxy would qualify as a superb vaccuum here on earth....intergalactic space might only have a few "particles) per cubic cm.Out there, there are no objects to pull in, and darn few atoms or molecules as well. <br /> Posted by MeteorWayne</DIV></p><p>Look out for rogue black holes floating throughout the universe. Sounds like a good plot for a space movie... I should start writing now... lol </p> <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Look out for rogue black holes floating throughout the universe. Sounds like a good plot for a space movie... I should start writing now... lol <br /> Posted by deapfreeze</DIV></p><p>It's not science fiction:</p><h2>Superkick: Black hole expelled from its parent galaxy</h2> <h3>Gravitational rocket propelled the monster at a speed of thousands of kilometres per second</h3> <p> <strong> By an enormous burst of gravitational waves that accompanies the merger of two black holes the newly formed black hole was ejected from its galaxy. This extreme ejection event, which had been predicted by theorists, has now been observed in nature for the first time. The team led by Stefanie Komossa from the Max Planck Institute for extraterrestrial Physics (MPE) thereby opened a new window into observational astrophysics. The discovery will have far-reaching consequences for our understanding of galaxy formation and evolution in the early Universe, and also provides observational confirmation of a key prediction from the General Theory of Relativity (Astrophysical Journal Letters, May 10, 2008).</strong> </p><p>Rest of article here:</p><p>http://www.mpe.mpg.de/Highlights/PR20080429/text.html</p><p>Preprint of published paper:</p><p>http://xxx.lanl.gov/abs/0804.4585</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[deapfreeze]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It's not science fiction:</DIV><br /><br />Hey derekmcd&nbsp;thanks for the post.. It clears up some of my thinking and it was a good read.. <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>