by BDanielMayfield » Thu May 22, 2014 3:59 am
Boomer12k wrote:My allusion to a "drain" was purely visual observation. Maybe an Eddy Pool is more likely.
:---[===] *
Comparisons of spiral galaxies to rotating fluidic systems like whirlpools and cyclones is very understandable due to similar looking shapes, but unlike in whirlpools and cyclones, material in galaxies is not always in motion toward the center. Due to the nature of orbits, at any given time just about as much matter (stars, gas and dust, etc.) will be moving away from the center as what is falling toward it. Much material will also be in circular or very nearly circular orbits with no or very slight motion toward or away from the center.
I can imagine though that many people when seeing a photo of a spiral galaxy might think that everything in a spiral's arms might be "flowing" along the arms down toward the core region of the galaxy, like water circling a drain, which would be a misconception.
Bruce,
Don't bring me down the drain Mayfield
![:) :ssmile:](./images/smilies/smile.gif)
[quote="Boomer12k"]My allusion to a "drain" was purely visual observation. Maybe an Eddy Pool is more likely.
:---[===] *[/quote]
Comparisons of spiral galaxies to rotating fluidic systems like whirlpools and cyclones is very understandable due to similar looking shapes, but unlike in whirlpools and cyclones, material in galaxies is not always in motion toward the center. Due to the nature of orbits, at any given time just about as much matter (stars, gas and dust, etc.) will be moving away from the center as what is falling toward it. Much material will also be in circular or very nearly circular orbits with no or very slight motion toward or away from the center.
I can imagine though that many people when seeing a photo of a spiral galaxy might think that everything in a spiral's arms might be "flowing" along the arms down toward the core region of the galaxy, like water circling a drain, which would be a misconception.
Bruce, [i]Don't bring me down the drain[/i] Mayfield :ssmile: