I’d really appreciate it if someone could identify the other bright objects in this picture of Andromeda. If we imagine the centre of Andromeda as the centre of a clock, I’m most interested in:
the bright blue object at at about 2 o’clock, and, oh, half a galatic length from the centre
yellowish object at 7 o’clock, and about a galactic width from the centre
the yellowish object at 11 o’clock that just clears the galaxy
And of course, my favourite part of GQ is hearing about other interesting things that I didn’t ask about, so feel free to pass those on as well.
Perhaps someone knows precisely what the names of those objects are, but they’re probably just foreground stars that are between us and Andromeda. They look so big/bright relative to Andromeda because they’re much closer - in our own galaxy.
One of the more interesting objects in orbit around the Andromeda Galaxy is Mayall II, the largest globular cluster in the Local Group.
Despite being such a large object, it isn’t actually visible in that image as far as I can tell, so that suggests that every single object in that picture is a star in our galaxy (except the three galaxies already mentioned, (M110, M32 and M31 the Andromeda Galaxy itself).
Ooh, I think I can see one or two really distant galaxies in the background too (directly under M110, for instance) but I can’t currently find their catalog numbers.
Note the red circle in the star map for this Wiki article is misplaced. (The star in the OP’s photo is indeed Nu And, but the circle in that map is closer to Mu And. The rest of the Wiki article accurately describes Nu And.)
Thank you everyone - I’ve enjoyed looking up all the objects you mentioned!
Now, just so I have it straight, the consensus is that all (or almost all) of the littler lights that just look like stars are actually in front of Andromeda (from our perspective) not behind it? This blows my mind for a couple of reasons:
it certainly looks like those stars are shining through Andromeda, but in fact the stars are obscuring the galaxy
Andromeda is not in the same position of the sky as the Milky Way (here in the Northern Hemisphere, it is to the left of it, from the perspective of the viewer, yes?) So there are that many stars in our galaxy, but outside the Milky Way? Whoa.
Simster, glad you liked the image. Here’s another one I love that shows the actual size of Andromeda compared to the moon. Andromeda is huge! (Well, I know it’s a galaxy and all, but I mean even at the distance it is from Earth, it still is huge from our vantage point.) Can you imagine how awesome it would be if it was bright enough to actually see it in the sky? Anyway, I learned about that image from another thread on the Dope, but don’t have time to search to figure out who to give credit to.
You seem to be using “Milky Way” to mean “the arm of our galaxy – the Milky Way – which appears as a blurry river to the naked eye.”
Yes, ALL the stars we see with the naked eye (as individual stars) are part of our galaxy, the Milky Way. Most are rather close to us. Others are a it further, including the ones in that fuzzy “river” known also as “The Milky Way.” The only objects we can see with the naked eye outside our galaxy are the Andromeda Galaxy and the Magellanic Clouds.
It’s true the “blurry river” was named first, by ancient Greeks, long before we knew what it really was. So, we’re stuck with using “Milky Way” for two different things, only one of which has to do with milk.
It gets worse! The Greek word for “milk” gives us the word “galaxy” (notice the “lax,” as in “lactose,” etc.?). So the milk imagery was (perhaps inappropriately) extended twice: first when we realized we are in a big spiral thing called the Milky Way; and then again, when we realized there are many of these “galaxies.”
Yes! You’re right - I was speaking of the blurry river when I used the term Milky Way.
But what I find mind boggling is that there would be a virtual carpet of stars from within our own galaxy, even when viewing the region of the galaxy where the distribution is skimpiest. I knew from the Hubble Deep Field that there is a barrage of galaxies wherever we look way, way out there, but I hadn’t realized how densely populated the least-dense region of our own galaxy would be.
This is a small version of the same picture with a few annotations that appear when you mouse-over. So, correct about M32 and M110. The blue blob at about 10 o’clock is NGC 206, a star cluster within Andromeda.
Bummer about the forthcoming collision between Andromeda and the Milky Way. That should be an earth-shattering kaboom!*
not really. And the earth will no longer exist then anyway. Sigh!
Another factoid of interest – both M32 and M110 are dwarf elliptical galaxies that are believed to be satellite galaxies of Andromeda. They may once have been spiral galaxies that lost their spiral arms due to the tidal effects from Andromeda.
