Dwarf Galaxies Discovered

d'alz writes "Two new satellite galaxies have been discovered in the Milky Way. These dim dwarf galaxies bring the total number of galaxies in the Milky Way's cosmic neighborhood to a total of 14. Of course, theorists believe there could be a hundred more. The two dwarfs were found in the direction of the constellations Canes Venatici (the hunting dogs) and Bootes (the herdsman), scientists studying the Sloan Digital Sky Survey said in a statement. However, even though these galaxies are presumably quite close, they are difficult to spot, as they are very dim, which is a defining characteristic of dwarf galaxies."

Comments

Re:I've heard this before

[porkchop_d_clown]

These are new.

Through various techniques we're building up a more detailed understanding of the shape of our own galaxy - this is easy to do when looking at other galaxies, but quite hard to do for our own - imagine trying to get a detailed map of the human body from inside the stomach.

Since it's hard to tell how far away stars are, what they've been doing is gathering motion and spectrographic maps of them - figuring out which stars are obviously affecting each other, which stars are chemically similar and so on, and building 3d models from these.

It was just a year or two ago we figured out the Milky Way is in the middle digesting another smaller galaxy in the direction of Saggitarius.

Re:Basic question on naming...

[Anonymous Coward]

I can't answer your question, but I can share my suspicion that the distinction is made based upon such criteria as the trajectory of the little galaxy. If you had a galactic disk with a pretty uniform orbital speed and plane, you'd pretty much conclude that stars in that plane and orbit were original to the formation of the galaxy. But if you find a group of stars that are just way different, going faster and out of the plane, or whose trajectory could be traced to originating outside the galaxy, then you could make the conclusion that this group of stars, though it be smaller than many galactic clusters, originated seperately from the galaxy and are in fact, either their own galaxy, or the remaining remnant of one.

Re:PC

[thewiz]

Um, my wife is a dwarf and often corrects people who are PC.
She's been called:
Altitudenly-challenged
Vertically-challenged
Height-challenged
Diminutive
Little lady
Little mom (by kids)
etc.

and she's always quick to say, "I'm short/small! Get over it!"

I'm sure these galaxies feel the same way.