Picture of our galaxy

  • Thread starter jobyts
  • Start date
  • #1
201
44

Main Question or Discussion Point

How have we taken the picture of our own galaxy? All the milkyway pictures look like taken from outside the galaxy.
 

Answers and Replies

  • #2
berkeman
Mentor
57,693
7,720
How have we taken the picture of our own galaxy? All the milkyway pictures look like taken from outside the galaxy.
What pictures? Can you provide a link?
 
  • #3
201
44
What pictures? Can you provide a link?
You need a link to see the picture of our galaxy? Never mind.
 
  • #4
381
0
You need a link to see the picture of our galaxy? Never mind.
There are images of our galaxy from the outside? I would love a link too.
 
  • #5
201
44
There are images of our galaxy from the outside? I would love a link too.
I said it looks like. I would also be interested to see our galaxy's picture from outside.
 
  • #6
381
0
I said it looks like. I would also be interested to see our galaxy's picture from outside.
Then what pictures were you talking about in the OP?

When you look on the internet for pictures of the milky way the pictures you see of the galaxy from an outside perspective are all OTHER galaxies. They just appear similar to what our own galaxy would probably look like.
 
  • #7
DaveC426913
Gold Member
18,850
2,329
There are images of our galaxy from the outside? I would love a link too.
Me too!

I'd also like to talk to the person that took them...
 
  • #8
3
0
The pictures he is talking about are not pictures of other galaxies, but the artist conceptions you always see (seriously how do you guys not know what he is talking about)
 
  • #9
turbo
Gold Member
3,077
45
We have barely gotten probes out of our solar system. I sure would like to meet the folks that have imaged the MW from outside the galaxy. They'd be real old, though and might be cranky - best not to tick them off.
 
  • #10
Astronuc
Staff Emeritus
Science Advisor
18,824
2,051
  • #11
chroot
Staff Emeritus
Science Advisor
Gold Member
10,226
34
We have never taken a picture of our own galaxy from the outside. The Milky Way is some 100,000 light-years across, so you'd probably need to be 100,000 light-years away to really get a photograph of it. Since we've only had robotic spacecraft for some fifty years, none of which travel anywhere near the speed of light, it's clear that it would be quite some time before any such photograph could ever be made.

Astronomers spend a lot of time mapping the Milky Way, determining its structure from within. They have determined that the galaxy has structure, and spiral arms, such as the Perseus and Sagittarius arms. That information allows artists to make pretty good conceptual pictures of what it would look like from far away.

- Warren
 
  • #12
SpaceTiger
Staff Emeritus
Science Advisor
Gold Member
2,940
2
This thread cracked me. :rofl:

It would be an interesting project to simulate an image of the Milky Way from the outside using the images and data we've taken from inside. Perhaps not so scientifically interesting... but the press would like it.
 
  • #13
201
44
I see. I never thought the milkyway picture is completely an artist's impression (of course, with scientific evidence given in Austronuc's link http://www.atlasoftheuniverse.com/milkyway.html). I was assuming it was an extrapolation of the pictures of the nearby stars.

I wonder how they pin point our sun's location within the galaxy.
 
  • #14
russ_watters
Mentor
19,705
6,043
The pictures he is talking about are not pictures of other galaxies, but the artist conceptions you always see (seriously how do you guys not know what he is talking about)
They probably do, but the OP was incoherent, so they were getting him to clarify what he meant. Sometimes it helps a person figure out the answer for themselves.
 
  • #15
russ_watters
Mentor
19,705
6,043
It would be an interesting project to simulate an image of the Milky Way from the outside using the images and data we've taken from inside. Perhaps not so scientifically interesting... but the press would like it.
I would think we'd only be able to simulate a small portion of it, though. Anything more than a few thousand light years away (guess) would be obscured by dust/gas.
 
  • #16
SpaceTiger
Staff Emeritus
Science Advisor
Gold Member
2,940
2
I would think we'd only be able to simulate a small portion of it, though. Anything more than a few thousand light years away (guess) would be obscured by dust/gas.
That's certainly true -- it might be more accurate to say, though, that we'd be able to simulate it with decreasing precision the further one gets from the sun. On the level of individual stars, the gas and dust wouldn't even be the limiting factor, since our optical surveys haven't even begun to probe the entire unobscured volume of the galaxy. On much larger distances, we do have crude maps of the galaxy in wavelengths that can penetrate the gas and dust, such as radio and infrared, so we could use that information to make inferences about emission in other wavebands.

Perhaps even more interesting than the image itself would be its development with time. With the recent observations from SDSS and the coming of LSST, it's likely to see a great deal of improvement in the near future.
 
  • #17
DaveC426913
Gold Member
18,850
2,329
EseehC said:
The pictures he is talking about are not pictures of other galaxies, but the artist conceptions you always see (seriously how do you guys not know what he is talking about)
They probably do...
They do. :wink:


EseehC, you have made an assumption in the absence of facts.

Is he referring to artist conceptions? Or is he referring to real photos of other galaxies? We don't know unless he gives us references.

You may very well be giving him misinformation. Which is why we ask questions.
 
  • #18
201
44
They probably do, but the OP was incoherent, so they were getting him to clarify what he meant. Sometimes it helps a person figure out the answer for themselves.
I felt the earlier responses were a bit rude and sarcastic.

I thought my question was clear. Seems like I was wrong.
 
  • #19
201
44
They do. :wink:


EseehC, you have made an assumption in the absence of facts.

Is he referring to artist conceptions? Or is he referring to real photos of other galaxies? We don't know unless he gives us references.

You may very well be giving him misinformation. Which is why we ask questions.
"artist conceptions" was the answer to my question. I cannot put that in my question.
I clearly mentioned in my OP that it is about our galaxy.
 
  • #20
berkeman
Mentor
57,693
7,720
I felt the earlier responses were a bit rude and sarcastic.

I thought my question was clear. Seems like I was wrong.
Certainly didn't mean to be rude, but yes, we were being a little bit sarcastic. Your original post (OP) was quite clear about "taking pictures"

How have we taken the picture of our own galaxy? All the milkyway pictures look like taken from outside the galaxy.
which is physically impossible. That's why I asked for a link, so that you would go trying to find one, and see for yourself that none exist.

How does that old saying go?... "Give a person a fish, feed them for that day. Teach a person how to fish, and you feed them for a lifetime." o:)
 
  • #21
DaveC426913
Gold Member
18,850
2,329
I felt the earlier responses were a bit rude and sarcastic.
I think this one set the tone, hmm?:
You need a link to see the picture of our galaxy? Never mind.
 
  • #22
DaveC426913
Gold Member
18,850
2,329
"artist conceptions" was the answer to my question. I cannot put that in my question.
No, what you can do (as was asked) is point us to what you are talking about.
I clearly mentioned in my OP that it is about our galaxy.
That is an assumption. You do not know that what you are looking at is our galaxy. You may be referring to artist's conceptions, or they may well be pictures of other galaxies. We still don't know since you haven't shown us what you're talking about. Further, as berkeman points out:
Your original post (OP) was quite clear about "taking pictures"
How does that old saying go?... "Give a person a fish, feed them for that day. Teach a person how to fish, and you feed them for a lifetime." o:)
Indeed, this is in the spirit of PF.
 
  • #23
201
44
Certainly didn't mean to be rude, but yes, we were being a little bit sarcastic. Your original post (OP) was quite clear about "taking pictures"



which is physically impossible. That's why I asked for a link, so that you would go trying to find one, and see for yourself that none exist.

How does that old saying go?... "Give a person a fish, feed them for that day. Teach a person how to fish, and you feed them for a lifetime." o:)
Thanks for the clarification. That helped to ease out things.
 
  • #24
Astronuc
Staff Emeritus
Science Advisor
18,824
2,051
How does that old saying go?... "Give a person a fish, feed them for that day. Teach a person how to fish, and you feed them for a lifetime." o:)
The way I heard it from Click & Clack - the Tappit Brothers. It goes - "Give a person a fish, feed them for that day. Teach a person how to fish, and he sits in a boat all day and drinks beer." :biggrin:


As far as I know, the 'images' of the Milky Way spiral are based on mapping the arms by looking through the galaxy.

This is what I was looking for earlier:
http://apod.nasa.gov/apod/ap050825.html
Explanation: A recent survey of stars conducted with the Spitzer Space Telescope is convincing astronomers that our Milky Way Galaxy is not just your ordinary spiral galaxy anymore. Looking out from within the Galaxy's disk, the true structure of the Milky Way is difficult to discern. However, the penetrating infrared census of about 30 million stars indicates that the Galaxy is distinguished by a very large central bar some 27,000 light-years long. In fact, from a vantage point that viewed our galaxy face-on, astronomers in distant galaxies would likely see a striking barred spiral galaxy suggested in this artist's illustration. While previous investigations have identified a small central barred structure, the new results indicate that the Milky Way's large bar would make about a 45 degree angle with a line joining the Sun and the Galaxy's center. DON'T PANIC ... astronomers still place the Sun beyond the central bar region, about a third of the way in from the Milky Way's outer edge.
http://ssc.spitzer.caltech.edu/
http://www.spitzer.caltech.edu/Media/mediaimages/sig/sig05-010.shtml [Broken] <-about the image

First GLIMPSE Results on the Stellar Structure of the Galaxy
http://arxiv.org/abs/astro-ph/0508325

http://www.news.wisc.edu/11405
 
Last edited by a moderator:
  • #25
berkeman
Mentor
57,693
7,720
The way I heard it from Click & Clack - the Tappit Brothers. It goes - "Give a person a fish, feed them for that day. Teach a person how to fish, and he sits in a boat all day and drinks beer." :biggrin:
:rofl: Good thing I wasn't drinking anything when I read that. You would have owed me another keyboard! :rofl:
 

Related Threads on Picture of our galaxy

  • Last Post
Replies
9
Views
3K
Replies
4
Views
2K
  • Last Post
Replies
7
Views
3K
  • Last Post
2
Replies
25
Views
4K
  • Last Post
Replies
8
Views
3K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
9
Views
3K
Replies
9
Views
6K
  • Last Post
Replies
3
Views
4K
  • Last Post
Replies
6
Views
2K
Top