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dbackfan
2005-Oct-06, 10:29 PM
Do we ever face the center of our galaxy? Isn't the Milky Way only an arm of the galaxy? As we travel around the sun and spin on our axis, I would think that the sky would be as bright as day when we faced the center of the galaxy where the majority of its stars are located even though they are each light years apart. (I'm thinking of the photos of other spiral galaxies with their fat, bright centers.)

antoniseb
2005-Oct-06, 10:33 PM
The center of our galaxy is in the constellation Sagittarius. It is true that the very center is blocked from our view by dust clouds, but even without those clouds it would not be as bright as day.

dbackfan
2005-Oct-07, 02:37 AM
Thanks, antoniseb. I went out to look for Sagittarius, but there are clouds to the southwest tonight. So, are the stars that make up this constellation part of our galaxy or outside of it?

ngc3314
2005-Oct-07, 03:17 AM
Do we ever face the center of our galaxy? Isn't the Milky Way only an arm of the galaxy? As we travel around the sun and spin on our axis, I would think that the sky would be as bright as day when we faced the center of the galaxy where the majority of its stars are located even though they are each light years apart. (I'm thinking of the photos of other spiral galaxies with their fat, bright centers.)

Those photos have long exposures, and the eye doesn't see them as so bright even through a large telescope. That said, dust extinction of the galactic center is a big deal - a century ago, there were astronomers who argued that spirals could not be like the Milky Way becaue theur central surface brightnesses were so much higher. Once photographs whosing dust couds sunk in, that objection vanished. If we could peek around the dust lanes, the Milky Way would have a central surface brightness like that of, say, Andromeda - only much, much larger.

Disinfo Agent
2005-Oct-07, 01:31 PM
Thanks, antoniseb. I went out to look for Sagittarius, but there are clouds to the southwest tonight. So, are the stars that make up this constellation part of our galaxy or outside of it?Did you use a telescope? Even the Andromeda galaxy is barely noticeable to the naked eye.

JohnW
2005-Oct-07, 03:25 PM
Thanks, antoniseb. I went out to look for Sagittarius, but there are clouds to the southwest tonight. So, are the stars that make up this constellation part of our galaxy or outside of it?
Except for the Andromeda Galaxy (if you're in the Northern Hemisphere) and the Magellanic Clouds (Southern Hemisphere), everything you can see with the naked eye is part of our galaxy.

Titana
2005-Oct-07, 03:36 PM
Do we ever face the center of our galaxy? Isn't the Milky Way only an arm of the galaxy? As we travel around the sun and spin on our axis, I would think that the sky would be as bright as day when we faced the center of the galaxy where the majority of its stars are located even though they are each light years apart. (I'm thinking of the photos of other spiral galaxies with their fat, bright centers.)

Effectivly, we are on one arm of our galaxy,which makes it even more difficult to get a general view of its conjuntion. One of the most difficult regions to study is indeed the center of our galaxy, because between us and the center are gases and dust that complicate a direct observation.

(Imagine the center of our galaxy is aproximately 26,000 light years in distance).
Titana............

dbackfan
2005-Oct-07, 08:22 PM
Did you use a telescope? Even the Andromeda galaxy is barely noticeable to the naked eye.
No telescope. Our northeastern Arizona sky, when cloudless and moonless, is extremely good for viewing stars. However, a telescope is obviously a must. Thanks to everyone for your helpful information. Terri