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[Arata]

I was wondering, What if our galaxy isn't a full spiral, but has a ring of stars orbiting it's center, and we are outside of that ring, which is why we see a lot of dust?
I'm just wondering, since we never have been out of the galaxy to see what it really looks like.
I just want to know. I mean sure, there could be distortion on the edges of our galaxy that makes a ring like formation, but what if the ENTIRE galaxy is a ring?

[Chaotic Cow]

Can you show me what you mean?

[Arata]

Here's an image I made to show you what I mean (yellow dot indicates Sun's position.):

[Dan Dixon]

What if our galaxy isn't a full spiral, but has a ring of stars orbiting it's center...

Nice image. Well done.

It's interesting idea, but scientists are quite certain that our galaxy is a barred spiral galaxy.
http://en.wikipedia.org/wiki/Milky_Way#Spiral_arms

"Observations presented in 2008 by Robert Benjamin of the University of Wisconsin-Whitewater suggest that the Milky Way possesses only two major stellar arms: the Perseus arm and the Scutum-Centaurus arm."

Here is information about the image that is used in Universe Sandbox to depict our galaxy:
http://www.spitzer.caltech.edu/Media/releases/ssc2008-10/ssc2008-10b.shtml

[Chaotic Cow]

So they think we are in a Spiral Bar Center Galaxy with 2 Major Arms and a few minor arms.

[witold]

We have spiral-ringed galaxy

[Arata]

I would like to know how the know our galaxy is a BARRED spiral.

[atomic7732]

Because the way they tell distance of stars (parallax) and where they are placed they can make a virtual image of distances and... Tah dah!

I was gonna say: "How do you tell distance of a virtual sound?"
Edit: Although that ones kind of... more complicated...

[Dan Dixon]

I would like to know how the know our galaxy is a BARRED spiral.

That is a really great question. It's a good strategy to ask how we know something and not just believe it because someone told you that's they way it is.

Similar to what NeutronStar said, scientists are able to determine the distance of the stars in our galaxy using various techniques (including parallax) are able to plot out those distances to see that our galaxy has 2 main arms and a barred center.

The short answer is from observation. If the galaxy was a ring, like how you depicted it, the data would look very different.

These sites answers your question specifically:
http://www.astronomycafe.net/qadir/q2213.html (uses an outdated image of our galaxy showing four main arms)
http://curious.astro.cornell.edu/question.php?number=622

[monmarfori]

Spirals are not ringed. only polar ring galaxies and ring galaxies.