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MWGs satellite galaxies questions

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#1 CygnuS

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Posted 07 August 2019 - 06:49 PM

I was just flipping through some (not so) old Sky&T magazines and came across this..."the Magellanic Clouds are moving so fast that they can't be gravitationally bound to our Milky Way Galaxy--instead, they are first time visitors".

I don't remember ever knowing that but maybe I did and then forgot.  Since they are not gravitationally bound does that mean the Magellanic Clouds are not considered satellites and are not listed as such after 2012? How many satellites galaxies do we have?

The quote was in the June 2015 issue...page 23 by Govert Schilling and he was referring to an earlier piece in the Oct 2012 Sky&T...page 28


Edited by CygnuS, 07 August 2019 - 06:55 PM.


#2 llanitedave

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Posted 07 August 2019 - 10:10 PM

As far as I'm aware, that's not the scientific consensus.



#3 ILikePluto

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Posted 09 August 2019 - 04:59 PM

The previous post is correct.

 

The Magellanic Clouds are satellite galaxies of the Milky Way:  Knowable Magazine.

 

Hubble observations circa 2006 erroneously found that the two galaxies had such high speeds they might not be gravitationally bound to the Milky Way, but later and better work, also by Hubble, found lower speeds.  Although the two galaxies are making their first pass by the Milky Way, they are also bound to it:  Scientific American.

 

The statement you quote from the 2015 magazine was out-of-date and incorrect even then, and it's still out-of-date and incorrect now.

 

The current number of known satellite galaxies orbiting the Milky Way is 58, including the Magellanic Clouds.

 



#4 CygnuS

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Posted 10 August 2019 - 10:22 AM

58! I didn't think the entire Local Group even had that many. 



#5 rockethead26

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Posted 10 August 2019 - 05:41 PM

58! I didn't think the entire Local Group even had that many. 

Astronomers have found a lot of very dim dim dwarf galaxies in the last few years.




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