At the Solar System’s present point in its 300,000,000-year orbit through the Galaxy, our view of the galactic core is obscured by dust clouds. I’m wondering if there are any good speculations as to what the Core would look like to us (normal naked-eye vision) if those clouds were not present or if we were at some point in the galactic orbit where they didn’t obscure it.
I think our view will always be obscured - the problem is that the plane where most of the stuff hangs out in our galaxy is chock-full of dusty goodness. If we took a space ship up out of that plane and got a better view, I think we’d look pretty much like the Andromeda Galaxy, which is another large spiral galaxy like ours, and has the advantage that it’s pretty close by (as galaxies go, anyway).
Problem is, the Andromeda Galaxy (alias M31) is an ordinary, garden-variety spiral galaxy. Infrared and radio observations, at frequencies not blocked by dust, have shown that our own Milky Way galaxy is most likely a barred spiral. The central bulge of a barred spiral looks pretty different from that of the non-barred variety.
[channelling = Dave Bowman]It’s full of stars![/channelling]
Another thing to keep in mind that the pictures of galaxies like Andromeda are time lapse. The bulk of a galaxy is really quite faint. We are inside a galaxy and I can’t ever see the Milky Way in my area due to light pollution.
When it comes to an “distance view” of galaxy, the shape pretty much doesn’t matter. It’ll be a bright smear of a core and a very faint haze around it. (So SF film scenes like the ending of “Empire” are not realistic)
Without the dust around the core, my WAG is that a galactic core would be amazingly bright. After all, the Andomeda core is visible to the naked eye from a looong way off, dust and all.
[Inigo Montoya]You keep using that word. I do not think it means what you think it means. [/IM]
Time lapse is a cinematography where distinct frames are shot at a slower than normal rate to show motion of extremely slow objects. Long exposures are typically used for astrophotography. It may be noted that Andromeda as it is bright enough to be seen with the naked eye in a dark sky and is the most distant such object.
Much like GHW Bush’s “Thousand Points of Light” program. Except it actually would be.
I thought there was some kind of imprisoned “god” figure at the center of the galaxy.
True – there’s a rather big dust feature through the centre of our Galaxy’s bulge for starters. This is NGC1300, a very nearby barred spiral. Compared to the core of Andromeda, our galaxy probably has a lot more dust in it, rather like NGC1300.
Do you mean seeing other galaxies in the distance? Because if you do, we can tell the difference between different galaxies, and can make out the shapes of them, even with shortish exposure times, and a spiral galaxy looks very different to an elliptical.
I think he means that if you were out in intergalactic space, and looked at a “nearby” galaxy, that it would look to your eyes like a whitish smear near the core and a faint mist around that, even if your eyes were adjusted for the darkness, becuase our eyes aren’t sensitive enough to show up colors and details like you see in those beautiful photographs.
That’s what I thought he was saying. However, if you look at Andromeda, with an amateur telescope, i.e. one that you simply look through, where all the optics do is magnify rather than anything really fancy, then you should be able to see structure such as the spiral arms of Andromeda. So, I think that if you were close enough to a galaxy, you could see structure with the naked eye.
Although, if Andromeda were close enough to us so that we could see structure such as the spiral arms with the naked eye, I think we’d probably have bigger things to worry about, such as our Galaxy and Andromeda about to (relatively) go kaboom.
What would cause them to kaboom? They could collide, of course, but that’s nothing to worry about.
Note that the spiral structure of the (then) Andromeda Nebula wasn’t discovered until 1887 and then using photography. For the longest time it was thought to be a close nebula. Hubble was the first to actually photograph individual stars (1923) and then prove it was a galaxy (1929). This required state-of-the art telescopes as well as photography.
Some links:
Andromeda Galaxy info Note the links to amateur photos, very long exposures with the exceptions of those using CCDs. (But even 90 second exposures are not comparable to what the naked eye sees.)
M33 Galaxy info. Two things to note especially: M33 is said here to be the farthest object visible to the naked eye. It also has an apparent diameter 4 times the size of the moon.
Does anyone here think we’ve somehow all missed seeing the spirals of a galaxy 4 times the size of the moon with our naked eyes???
(And yeah, time lapse->brain lapse->brain fart.)
I was being metaphorical, and referring to the collision, which really shouldn’t affect us at all. 
Of course, there is the argument that any major merger event (such as us colliding with Andromeda) will set the central black hole into active mode, in which case, I think the core would become very bright, very quickly, especially in the optical, and maybe also in the radio wavebands. I wonder how that’d affect us.
Bear in mind they’re also rather far away. But then, maybe my colleagues who do optical astronomy lied to me when they said that you can see the arms through a good telescope. The stuff I look at, our eyes definitely aren’t designed to see.
I’ve personally seen the arms (and even dust lanes) of M31 through an amateur, eyeball-on-the-eyepiece, telescope. But it was a 20 inch telescope, at an excellent dark site, on a very clear night. The features were quite clear under those circumstances, so you could presumably get away with something less if you only wanted to just barely see them, but I’ven’t experimented too much with lesser scopes or worse conditions to say exactly what the threshhold would be.
Like the Gum Nebula, it’s large (in terms of area of the visual sky occupied) but so dim that long-exposure photography is required to make it visible. It makes one wonder if you could just set up a camera on a motorized telescope mount (so it will track the image across the sky) without a telescope and set for long exposure, and get a picture of M-33 “as it would appear to the naked eye” if we could perceive that dim an image.
The other point is that the core is visible with the naked eye as a dim speck only to people with exceptionally good eyesight. That’s why the apparently contradictory “M-31/M-33 is the farthest visible object” factoids – for most people, it’s M-31; for those with outstanding eyesight, M-33.
I don’t know if this is what you’re after Polycarp, but this page (scroll down a couple times) shows the Milky Way as it appears in various wavelengths, from our position inside it.
The “Near Infrared” image might be helpful for imagining what the Milky Way would look like in the optical band, were it not for the dust clouds. (I’m sure it wouldn’t be as bright in our sky as it seems on the web page though.)
Oh, no! We’d better get ready!
Wait a minute–three **billion ** years?
What a relief–I thought it said three *million * years.
