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

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 4522
Joined: Fri Dec 04, 2009 3:27 am

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

Post by APOD Robot » Wed Jul 30, 2014 4:10 am

Image 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.

<< Previous APOD This Day in APOD Next APOD >>
[/b]

User avatar
Ann
4725 Å
Posts: 11705
Joined: Sat May 29, 2010 5:33 am

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

Post by Ann » Wed Jul 30, 2014 6:10 am

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.
Image
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
Color Commentator

User avatar
owlice
Guardian of the Codes
Posts: 8389
Joined: Wed Aug 04, 2004 4:18 pm
Location: Washington, DC

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

Post by owlice » Wed Jul 30, 2014 12:14 pm

Ann wrote: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!
A closed mouth gathers no foot.

Bersonic
Ensign
Posts: 19
Joined: Mon Feb 03, 2014 3:45 am

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

Post by Bersonic » Wed Jul 30, 2014 12:42 pm

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

CURRAHEE CHRIS
Science Officer
Posts: 105
Joined: Mon Sep 30, 2013 4:04 pm
Location: Mechanicsburg Pa.

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

Post by CURRAHEE CHRIS » Wed Jul 30, 2014 12:49 pm

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
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

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

Post by Boomer12k » Wed Jul 30, 2014 3:37 pm

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

:---[===] *

User avatar
Psnarf
Science Officer
Posts: 317
Joined: Fri Feb 26, 2010 6:19 pm

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

Post by Psnarf » Wed Jul 30, 2014 3:49 pm

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
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

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

Post by Boomer12k » Wed Jul 30, 2014 3:55 pm

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
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

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

Post by Boomer12k » Wed Jul 30, 2014 4:01 pm

Psnarf wrote: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

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

Post by tom p » Wed Jul 30, 2014 4:07 pm

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?

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18711
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Arty-factual

Post by neufer » Wed Jul 30, 2014 4:32 pm

tom p wrote:
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?
http://robgendlerastropics.com/M31text.html wrote:
<<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.>>
Art Neuendorffer

User avatar
Chris Peterson
Abominable Snowman
Posts: 16303
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

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

Post by Chris Peterson » Wed Jul 30, 2014 4:56 pm

tom p wrote: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).
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

hlwelborn
Ensign
Posts: 29
Joined: Thu Feb 10, 2011 7:00 pm
Location: Pacific Northwest

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

Post by hlwelborn » Wed Jul 30, 2014 4:59 pm

Outstanding!

User avatar
geckzilla
Ocular Digitator
Posts: 9158
Joined: Wed Sep 12, 2007 12:42 pm
Location: Modesto, CA

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

Post by geckzilla » Thu Jul 31, 2014 4:00 am

Boomer12k wrote:
Psnarf wrote: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
You do not have the required permissions to view the files attached to this post.
Just call me "geck" because "zilla" is like a last name.

Boomer12k
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

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

Post by Boomer12k » Thu Jul 31, 2014 6:29 am

geckzilla wrote:
Boomer12k wrote:
Psnarf wrote: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
Telescope Nerd
Posts: 122
Joined: Thu Sep 23, 2010 5:15 pm

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

Post by NGC3314 » Thu Jul 31, 2014 1:21 pm

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.
You do not have the required permissions to view the files attached to this post.

starsurfer
Stellar Cartographer
Posts: 4610
Joined: Thu Mar 15, 2012 7:25 pm

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

Post by starsurfer » Thu Jul 31, 2014 1:33 pm

Click to play embedded YouTube video.

ta152h0
Schooled
Posts: 1398
Joined: Mon Aug 29, 2005 12:46 am
Location: Auburn, Washington, USA

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

Post by ta152h0 » Thu Jul 31, 2014 7:28 pm

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

User avatar
bystander
Apathetic Retiree
Posts: 20830
Joined: Mon Aug 28, 2006 2:06 pm
Location: Oklahoma

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

Post by bystander » Thu Jul 31, 2014 8:17 pm

ta152h0 wrote:wonder how many girls born today are named " Andromeda " ?
I would guess not many, too hard to misspell.
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

ta152h0
Schooled
Posts: 1398
Joined: Mon Aug 29, 2005 12:46 am
Location: Auburn, Washington, USA

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

Post by ta152h0 » Thu Jul 31, 2014 10:51 pm

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.
Wolf Kotenberg

User avatar
LocalColor
Science Officer
Posts: 266
Joined: Sat Mar 31, 2012 9:11 pm
Location: Central Idaho, USA

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

Post by LocalColor » Fri Aug 01, 2014 1:41 am

Very nice image.

From our back yard with a Canon 7D camera and Canon 400 mm lens f2.8 (right side up) :wink:
m31-20140701-b.jpg
You do not have the required permissions to view the files attached to this post.

starsurfer
Stellar Cartographer
Posts: 4610
Joined: Thu Mar 15, 2012 7:25 pm

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

Post by starsurfer » Sat Aug 02, 2014 6:11 pm

LocalColor wrote:Very nice image.

From our back yard with a Canon 7D camera and Canon 400 mm lens f2.8 (right side up) :wink:
m31-20140701-b.jpg
This is one of the few times I don't prefer north up! :D

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18711
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

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

Post by neufer » Sat Aug 02, 2014 7:16 pm

bystander wrote:
ta152h0 wrote:
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".
Art Neuendorffer

User avatar
Nitpicker
Inverse Square
Posts: 2692
Joined: Fri Sep 20, 2013 2:39 am
Location: S27 E153

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

Post by Nitpicker » Mon Aug 04, 2014 4:58 am

neufer wrote: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.)

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18711
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

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

Post by neufer » Mon Aug 04, 2014 8:34 pm

Nitpicker wrote:
neufer wrote:
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.
Nitpicker wrote:
(Must be a more popular name than Perseus.)
http://www.behindthename.com/name/percy wrote: <<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'.>>
Art Neuendorffer