APOD: M31: The Andromeda Galaxy (2014 Jul 30)

[APOD Robot]

M31: The Andromeda Galaxy

Explanation: Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two million years for light to reach us from there. Although visible without aid, the above image of M31 was taken with a standard camera through a small telescope. Much about M31 remains unknown, including how it acquired its unusual double-peaked center.

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[Ann]

APOD Robot wrote:
...the above image of M31 was taken with a standard camera through a small telescope.

At first I was a little disappointed at the quality of today's APOD. But in view of how the image was acquired, with simple equipment during a single night of a star party, it is great.

I have previously written that the pictures chosen as APODs often teach us about the universe by staying close to the Earth, so that the pictures are easier to understand. Today's APOD represents another way to reach out to the general public: by showing people how much can be accomplished without super-advanced equipment. This APOD pretty much amounts to an exhortation to the astronomically interested general public: buy yourself a camera and a small telescope, and go outside at night and shoot splendid images of another galaxy!

Ann

[owlice]

This APOD pretty much amounts to an exhortation to the astronomically interested general public: buy yourself a camera and a small telescope, and go outside at night and shoot splendid images of another galaxy!

Not the message I got at all from this APOD, nor am I disappointed in it. It's a lovely clear image of a big beautiful spiral galaxy, and I feel fortunate to see it! Great job, Jason!

[Bersonic]

Thank you guys! This is a huge honor for me!

[CURRAHEE CHRIS]

The name "Andromeda" is such a pretty name and when you see the galaxy, one understands why. I found today's picture very informative for novices like myself.

[Boomer12k]

That is an AWESOME PICTURE!!!
Such good focus and detail....just great!!!

:---[===] *

[Psnarf]

Are there any stars that belong to Andromeda visible in this image? The outer blue ring is all local stars? The galaxies above and below Andromeda, M32 and M110, are definitely too far away to resolve individual stars in this image. The imagination is staggered to think there are billions of individual stars in those two regions of diffuse light, as is the inner region with more and more stars the closer you get to the center. This is what the galaxy looked like 2.5 million years ago. I imagine M32 and M110 are much closer today. Has anyone seen my apparently misplaced Tardis?

[Boomer12k]

I am sorry...but...."through a small telescope"....IS NOT WHAT YOU THINK.....he has a VIXEN APO telescope MADE FOR THIS TYPE OF WORK...and his Nikon D5300...is nothing to Sneeze at....at around 800 bucks. He is also not just "holding" a camera up to an eyepiece....like I once did....

This is a very good, high end professional set up...This is not a 30 dollar, 3 mega pixel camera, and a 100 dollar "small telescope" from Wal-mart....this is fairly high grade stuff. My Jason, and a SiPIX....it is not.....

Still a VERY NICE SHOT....don't get me wrong....but it was not "done on the cheap"....

:---[===] *

[Boomer12k]

Are there any stars that belong to Andromeda visible in this image? The outer blue ring is all local stars? The galaxies above and below Andromeda, M32 and M110, are definitely too far away to resolve individual stars in this image. The imagination is staggered to think there are billions of individual stars in those two regions of diffuse light, as is the inner region with more and more stars the closer you get to the center. This is what the galaxy looked like 2.5 million years ago. I imagine M32 and M110 are much closer today. Has anyone seen my apparently misplaced Tardis?

From what I see.....NO...there are no resolved stars in the Andromeda Galaxy in this image. The "outer blue Ring"...is not local... but apart of the RIM of the Andromeda Galaxy. All of the "SPECKLES" would be stars in OUR galaxy.
The Galaxies maybe CLOSER today...but that light still won't reach us for a very long time.....

It think...THE DOCTOR borrowed your Tardis....

:---[===] *

[tom p]

This is one of the few photos I've seen that shows there's a bright dot in the center of M31 (usually all of the middle is washed out). When I've looked at M31 in telescopes, I've always been struck by the stellar-like bright dot in the center of the galaxy. What is it?

[neufer]

This is one of the few photos I've seen that shows there's a bright dot in the center of M31 (usually all of the middle is washed out). When I've looked at M31 in telescopes, I've always been struck by the stellar-like bright dot in the center of the galaxy. What is it?

<<The brighter [central M31] light source P1 is artifactual and has its basis in the eccentricity of the rotating circumnuclear stellar disk. It seems that the appearance of the two extremes of the ellipsoidal orbit creates an illusion of a second bright region towards our line of site. Several other galaxies are known which possess a true double nucleus however in these cases the second nucleus was most likely acquired in a previous merger event.>>

[Chris Peterson]

This is one of the few photos I've seen that shows there's a bright dot in the center of M31 (usually all of the middle is washed out). When I've looked at M31 in telescopes, I've always been struck by the stellar-like bright dot in the center of the galaxy. What is it?

It's just the core, where the stars are densest. All astroimages are substantially contrast compressed, so they don't do a good job of representing the visual appearance of the galaxy. There is a huge brightness range from inside to out. Our eyes only see clearly the very bright core, which telescopically looks nearly stellar because it is so small (and because M31 is usually viewed at fairly low magnification because of its great size).

[hlwelborn]

Outstanding!

[geckzilla]

Are there any stars that belong to Andromeda visible in this image? The outer blue ring is all local stars? The galaxies above and below Andromeda, M32 and M110, are definitely too far away to resolve individual stars in this image. The imagination is staggered to think there are billions of individual stars in those two regions of diffuse light, as is the inner region with more and more stars the closer you get to the center. This is what the galaxy looked like 2.5 million years ago. I imagine M32 and M110 are much closer today. Has anyone seen my apparently misplaced Tardis?

From what I see.....NO...there are no resolved stars in the Andromeda Galaxy in this image. The "outer blue Ring"...is not local... but apart of the RIM of the Andromeda Galaxy. All of the "SPECKLES" would be stars in OUR galaxy.
The Galaxies maybe CLOSER today...but that light still won't reach us for a very long time.....

It think...THE DOCTOR borrowed your Tardis....

:---[===] *

This is not totally true. There are a lot of foreground stars from our Milky Way, but not all of them that look like foreground stars are. When the picture is adjusted to be brighter it becomes nearly impossible to tell the difference between a globular cluster and an individual Milky Way star, but Andromeda hosts hundreds of globular clusters and these are easily seen in this image. Are you going to be able to tell which is which just from looking at them? Probably not. They're mostly fainter but that's not much to go on. Here is a screenshot from Aladin of some of the globular clusters of Andromeda. Note that there are plenty more far away from the galaxy which I didn't even load. You could easily take these data and overlay them on Bersonic's image to figure out which ones he managed to capture. He probably already did it himself.

[Boomer12k]

Are there any stars that belong to Andromeda visible in this image? The outer blue ring is all local stars? The galaxies above and below Andromeda, M32 and M110, are definitely too far away to resolve individual stars in this image. The imagination is staggered to think there are billions of individual stars in those two regions of diffuse light, as is the inner region with more and more stars the closer you get to the center. This is what the galaxy looked like 2.5 million years ago. I imagine M32 and M110 are much closer today. Has anyone seen my apparently misplaced Tardis?

From what I see.....NO...there are no resolved stars in the Andromeda Galaxy in this image. The "outer blue Ring"...is not local... but apart of the RIM of the Andromeda Galaxy. All of the "SPECKLES" would be stars in OUR galaxy.
The Galaxies maybe CLOSER today...but that light still won't reach us for a very long time.....

It think...THE DOCTOR borrowed your Tardis....

:---[===] *

This is not totally true. There are a lot of foreground stars from our Milky Way, but not all of them that look like foreground stars are. When the picture is adjusted to be brighter it becomes nearly impossible to tell the difference between a globular cluster and an individual Milky Way star, but Andromeda hosts hundreds of globular clusters and these are easily seen in this image. Are you going to be able to tell which is which just from looking at them? Probably not. They're mostly fainter but that's not much to go on. Here is a screenshot from Aladin of some of the globular clusters of Andromeda. Note that there are plenty more far away from the galaxy which I didn't even load. You could easily take these data and overlay them on Bersonic's image to figure out which ones he managed to capture. He probably already did it himself.

m31_globularclusters.png

Thanks Geckzilla. I think you are right. Clicking on the image and going to the magnified shot, I can make out some globulars....I think. One is to the left of M32...and another on above....that I think I can make out....ALSO....I think I am wrong about some resolved stars....on the left side of M31 in the magnified image...there are places that are more resolved. But I don't know if those are INDIVIDUAL STARS...or not...

Sorry for my Misperception....

:---[===] *

[NGC3314]

I'm pretty sure individual stars show up in a few places, although you'd need independent data to be sure which ones are single stars and which are clusters. I have an image of NGC 206 (the bright star cloud almost due left of M31's core in the APOD), the area where Hubble found Cepheids in the famous pictures from Mt. Wilson. Ignoring for now which ones of the bright blue stars in it are binaries rather than single, comparison shows that many of the bright specks in the APOD image in this area are individual stars.

[starsurfer]

Click to play embedded YouTube video.

[ta152h0]

wonder how many girls born today are named " Andromeda " ?

[bystander]

wonder how many girls born today are named " Andromeda " ?

I would guess not many, too hard to misspell.

[ta152h0]

one more. Is 2 million light years away too far away for any gravitational forces from the Milky Way to affect Andromeda ? I see a wobble.

[LocalColor]

Very nice image.

From our back yard with a Canon 7D camera and Canon 400 mm lens f2.8 (right side up)

[starsurfer]

Very nice image.

From our back yard with a Canon 7D camera and Canon 400 mm lens f2.8 (right side up)

m31-20140701-b.jpg

This is one of the few times I don't prefer north up!

[neufer]

wonder how many girls born today are named " Andromeda" ?

I would guess not many, too hard to misspell.

Andromeda is not among the top 4,275 U.S. female names.

ANDROMEDA: "to think of a man" from the Greek element ανδρος (andros) "of a man"

• combined with μηδομαι (medomai) "to think, to be mindful of".

[Nitpicker]

Andromeda is not among the top 4,275 U.S. female names.

ANDROMEDA: "to think of a man" from the Greek element ανδρος (andros) "of a man"

• combined with μηδομαι (medomai) "to think, to be mindful of".

http://en.wikipedia.org/wiki/Andromeda_(mythology) says this:

Her name is the Latinized form of the Greek Ἀνδρομέδα (Androméda) or Ἀνδρομέδη (Andromédē): "ruler of men", from ἀνήρ, ἀνδρός (anēr, andrós) "man", and medon, "ruler".

(Must be a more popular name than Perseus.)

[neufer]

ANDROMEDA: "to think of a man" from the Greek element ανδρος (andros) "of a man"

• combined with μηδομαι (medomai) "to think, to be mindful of".

http://en.wikipedia.org/wiki/Andromeda_(mythology) says this:

Her name is the Latinized form of the Greek Ἀνδρομέδα (Androméda) or Ἀνδρομέδη (Andromédē): "ruler of men", from ἀνήρ, ἀνδρός (anēr, andrós) "man", and medon, "ruler".

Neither seems quite appropriate, somehow.

Either: 1) You have Cetus Strait

• 2) or "ANDROMEDA" is still up for de bait.

(Must be a more popular name than Perseus.)

[b][color=#0000FF]Popularity for PERCY in the United States[/color][/b]

---

<<PERCY: From an English surname which was derived from the name of a Norman town Perci, which was itself perhaps derived from a Gaulish given name which was Latinized as Persius. The surname was borne by a noble English family, and it first used as a given name in their honour. A famous bearer was Percy Bysshe Shelley (1792-1822), an English romantic poet whose works include 'Adonais' and 'Ozymandias'.>>