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If you think the Milky Way has only two satellite galaxies . . .

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#1 ILikePluto

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Posted 31 May 2019 - 11:16 AM

. . . you really should get out more!  The latest count is close to 60!

 

This link includes a very cool video showing the many satellite galaxies popping into view as they are discovered:  Knowable Magazine


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#2 llanitedave

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Posted 31 May 2019 - 09:09 PM

. . . you really should get out more!  The latest count is close to 60!

 

This link includes a very cool video showing the many satellite galaxies popping into view as they are discovered:  Knowable Magazine

I've seen Leo 1, but the rest of them, even the Magellanic Clouds, are beyond me!



#3 Keith Rivich

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Posted 02 June 2019 - 01:28 PM

. . . you really should get out more!  The latest count is close to 60!

 

This link includes a very cool video showing the many satellite galaxies popping into view as they are discovered:  Knowable Magazine

And most of them are tough to observe!

 

I'm at around 10 or so positive observations. Interestingly enough a fair number of these satellites have bright globular clusters that are easier to see then the host galaxies themselves.

 

These are always on my observing list when visiting really dark skies.



#4 sg6

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Posted 02 June 2019 - 01:46 PM

Isn't every globular cluster a satellite of the milky way?

They are minor globular galaxies so yes there are loads of them, and still many we cannot see = they are hiding on the other side of the milky way.



#5 Keith Rivich

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Posted 02 June 2019 - 05:54 PM

Isn't every globular cluster a satellite of the milky way?

They are minor globular galaxies so yes there are loads of them, and still many we cannot see = they are hiding on the other side of the milky way.

Not every globular originated in the Milky Way. Some, such as m54, formed within a galaxy of its own. When that host galaxy was captured by the Milky Way it became part of our system. We can tell that they are captured by the orbit it is in. Normal milky way globulars, for the most part, orbit in the same direction and on nearly the same plane as all of the other milky way denizens. Captured globulars have very distorted orbits.

 

http://sci.esa.int/g...-the-milky-way/



#6 ILikePluto

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Posted 10 June 2019 - 09:50 AM

The Knowable story is now on the radio:

 

John Batchelor Show:  The Milky Way is a Top-of-the-Line Galaxy Surrounded by Untold Satellite Galaxies

 



#7 ILikePluto

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Posted 25 July 2019 - 12:32 PM

A new galaxy orbiting the Milky Way has been discovered in Boötes:  Boötes IV: A New Milky Way Satellite Discovered in the Subaru Hyper Suprime-Cam Survey and Implications for the Missing Satellite Problem

 

This brings the total number of known satellite galaxies orbiting the Milky Way to 58.

 

The total number of known galaxies in the Local Group exceeds 100.  Most are satellite galaxies of either the Milky Way or the Andromeda Galaxy.



#8 CygnuS

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Posted 12 August 2019 - 10:09 AM

Is there a minimum size they have to be in order to be labeled a "galaxy"? 




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