galactic satellites

[zarnic]

I recently read an article about a "rogue" galaxy that is a satellite of the larger Adromeda galaxy. This instantly created questions in my mind. Can galaxies, like planets, have saltellites? That would mean smaller galaxies would be able to change direction inorder to rotate ... can they? <div class="Discussion_UserSignature"> <p><em>Wisdom doesn't automatically come with old age. Nothing does - except wrinkles.</em> A. Van Buren, 1978<br />* <em>An unbreakable toy is useful for breaking other toys.</em>  -- according to Van Roy</p> </div>

 

[MeteorWayne]

Yes galaxies can have satellites for a time.<br />In most cases, they don't orbit intact for too long before the gravity of the larger galaxy tears the smaller one apart. This is from the gravity being stronger on the close side of the smaller one compared the far side where the pull is weaker due to greater distance from the center of the larger galaxy. The smaller galaxy also often pulls material out from the larger galaxy.<br /><br />But up until disruption, it's just like a satellite orbiting the earth, or a planet around the sun.<br />If the smaller mass traveling around the larger mass at the right speed, it will orbit.<br /><br />From a gravitational point of view, the smaller object isn't changing direction.<br />From a physical point of view, gravity is pulling it down at the same speed asthe ground (or larger galaxy) falls away.<br />That's an orbit. <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>

 

[zarnic]

Thank You, MW. <div class="Discussion_UserSignature"> <p><em>Wisdom doesn't automatically come with old age. Nothing does - except wrinkles.</em> A. Van Buren, 1978<br />* <em>An unbreakable toy is useful for breaking other toys.</em>  -- according to Van Roy</p> </div>

 

[willpittenger]

In fact, the Milky Way has at least two satellites plus the remains of a third. Both of the Magellanic Clouds are satellite galaxies. The Milky Way is in the process of "digesting" them. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[MeteorWayne]

The assrtion that the Magellanic Clouds are satellites of the Milky Way has been placed in dispute with some recent observations. They may be moving too fast to be in orbit.<br /><br />All the other dwarf galaxies are well along the path to disruption (and digestion as you suggest). There are at least half a dozen, IIRC.)<br /><br />MW <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>

 

[willpittenger]

Digestion in progress: Burp. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[vandivx]

"The assrtion that the Magellanic Clouds are satellites of the Milky Way has been placed in dispute with some recent observations. They may be moving too fast to be in orbit."<br />http://space.newscientist.com/article/dn12652-milky-way-keeps-a-light-grip-on-speedy-neighbours.html<br />http://space.newscientist.com/article/dn10916-speeding-dwarfs-upset-galactic-family-picture.html<br />DM at work?<br /><br />on topic http://space.newscientist.com/article/dn11980<br /><br />vanDivX <div class="Discussion_UserSignature"> </div>