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Fraser
2007-Jan-13, 01:51 AM
There's new easy way to put this, our home galaxy is a killer. It's torn up galaxies in the past, and it's going to do it again in the future. Each galaxy we consume makes us larger. ...

Read the full blog entry (http://www.universetoday.com/2007/01/12/the-milky-way-and-the-seven-dwarfs/)

ArgoNavis
2007-Jan-23, 04:17 AM
So in addition to the known 15 satellite dwarfs:

Canis Major (CMa)
Sagittarius (Sgr)
Large Magellanic Cloud (LMC)
Small Magellanic Cloud (SMC)
Bootes (Boo)
Ursa Minor (UMi)
Draco (Dra)
Sextans (Sex)
Sculptor (Scl)
Ursa Major (UMa)
Carina (Car)
Fornax (For)
Leo II
Canes Venatici (CVn)
Leo I

http://www.astro.uu.se/~ns/mwsat.html

we now have:

Canes Venatici II
Canes Venatici III
Bootes II
Leo T
Coma Berenices
Ursa Major II
Hercules.

total inventory of 22.

suitti
2007-Jan-23, 04:10 PM
When i was a kid, everyone knew that the Small and Large Megelanic Clouds were in the process of being eaten up. But lately there was news that at least one of these (which one?) is moving too fast to be eaten this time around. It will take at least another pass for that to happen.

I can hardly wait.

kzb
2007-Jan-23, 06:54 PM
When they model these galaxy interactions, do they have to take account of dark matter mass?

dirty_g
2007-Jan-24, 02:40 PM
So in addition to the known 15 satellite dwarfs:

Canis Major (CMa)
Sagittarius (Sgr)
Large Magellanic Cloud (LMC)
Small Magellanic Cloud (SMC)
Bootes (Boo)
Ursa Minor (UMi)
Draco (Dra)
Sextans (Sex)
Sculptor (Scl)
Ursa Major (UMa)
Carina (Car)
Fornax (For)
Leo II
Canes Venatici (CVn)
Leo I

http://www.astro.uu.se/~ns/mwsat.html

we now have:

Canes Venatici II
Canes Venatici III
Bootes II
Leo T
Coma Berenices
Ursa Major II
Hercules.

total inventory of 22.

I must have the wrong end of the stick. are you telling me the stars in the constellation of Canis Major and Bootes and even ursa major are actually satellite dwarfs?? I must misunderstand.

Amber Robot
2007-Jan-24, 02:46 PM
I must have the wrong end of the stick. are you telling me the stars in the constellation of Canis Major and Bootes and even ursa major are actually satellite dwarfs?? I must misunderstand.

Not the major stars of the constellation. The dwarf galaxies are named after the constellation in the sky in which they reside.

dirty_g
2007-Jan-24, 07:56 PM
Can you see them with a home telescope? Say an 6" Reflector?? :think:

Amber Robot
2007-Jan-24, 08:04 PM
Can you see them with a home telescope? Say an 6" Reflector?? :think:

Probably not. These things are extremely low surface brightness and I think that many, if not most, are actually discovered using color-magnitude diagrams.

crosscountry
2007-Jan-24, 08:17 PM
When i was a kid, everyone knew that the Small and Large Megelanic Clouds were in the process of being eaten up. But lately there was news that at least one of these (which one?) is moving too fast to be eaten this time around. It will take at least another pass for that to happen.

I can hardly wait.

My bet is that you cannot.

So is galaxy capture a cause of stellar formation? new material?

ArgoNavis
2007-Jan-25, 09:54 AM
My bet is that you cannot.

So is galaxy capture a cause of stellar formation? new material?

Galaxy interactions are believed to be a cause of star formation, and galaxies undergoing mergers and collision events are observed to have very high rates of star formation (much higher than the Milky Way's 1 or so solar mass per year) and are called starburst galaxies.

When 2 or more galaxies interact, then clouds of gas and dust will collide and compress to form stars. The collision and compression of interstellar gas clouds occurs inside most spiral galaxies and does lead to star formation, but at a lower rate.

Most elliptical galaxies have no interstellar clouds of gas and dust left to continue the star formation process, except where they merge with a spiral, such as what has happened to Centaurus A.

The other means of compressing the interstellar clouds of gas and dust is through a process of sequential star formation, where massive stars within gas clouds go supernova and their expelled and expanding material compresses other material to cause further star formation.