How bright could the Galactic Centre be (visible light)?
How bright could the Galactic Centre be (visible light)?
Relative to our sun, how bright could the Galactic Centre be (visible light) if there was no dust? Given the number of stars, would there be a solid line of light across the sky?
- JohnD
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Today's APOD purports to be the Milky Way, but is it? Or another galaxy (far, far away?) that happens to be of the same sort and seen edge on from here?
JOhn
(click here or scroll below - added by makc)
JOhn
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umm
if that was the case..
it'd be far far away....but reeeeeally close ,comparitivly (sp?)
yeah?
weird thought though![Smile :)](./images/smilies/icon_smile.gif)
it'd be far far away....but reeeeeally close ,comparitivly (sp?)
yeah?
weird thought though
![Smile :)](./images/smilies/icon_smile.gif)
The milky way is visible from all around the globe (ie. we're in the disk) - if it was another galaxy you would only see it in one direction.JohnD wrote:Today's APOD purports to be the Milky Way, but is it? Or another galaxy (far, far away?) that happens to be of the same sort and seen edge on from here?
Like the idea though - imagine everyone's response if they suddenly found out that we weren't in it!
![Surprised :o](./images/smilies/icon_surprised.gif)
I'm an Astrophysics Graduate from Keele University, England - doesn't mean I know anything but I might be able to help!
- JohnD
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Sorry to be pedantic, but no one has answered my question.
Which is, what is the galaxy shown in that APOD? It looks to be taken from outside the galaxy shown, so it can't be the Milky Way, as we're in it!
It could easily be a view of a distant galaxy seen edge on.
Or, as I think Empeda implies, this is a composite, like photos taken of the wals of a room from the centre and assembled into a 360 degree strip, or the panoramic pics from the Mars Rovers.
But which is it.
The caption is unclear.
I'll ask Serge Brunier
John
Which is, what is the galaxy shown in that APOD? It looks to be taken from outside the galaxy shown, so it can't be the Milky Way, as we're in it!
It could easily be a view of a distant galaxy seen edge on.
Or, as I think Empeda implies, this is a composite, like photos taken of the wals of a room from the centre and assembled into a 360 degree strip, or the panoramic pics from the Mars Rovers.
But which is it.
The caption is unclear.
I'll ask Serge Brunier
John
If it were it would have to be seriously close to us - we'd have noticed it I think!JohnD wrote: It could easily be a view of a distant galaxy seen edge on.
The image is a series of wide-angle exposures taken in Chile, so to answer your question - yes, it's a composite (but not a 360 degree one).
I'm an Astrophysics Graduate from Keele University, England - doesn't mean I know anything but I might be able to help!
- JohnD
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Confirmation from the source
All,
Serge Brunier has kindly replied to my query, as follows;
__________________________________________
:-(((((((((((
Dear John,
I'm frustrated by your mail : I think to this picture nearly one year before
to go to Chile to take it...
My intention was to SHOW OUR MILKY WAY AS IT WAS SEEN FROM OUTSIDE, as a Galaxy.............
Unfortunately, the bosses of APOD seems to not understood !!!!!!!!!
Anyway, of course, I m very happy to have been published in APOD !!
The picture was taken in last June, in Atacama desert, were the galactic
center is just overhead at midnight, with a fisheye lens...
Thanks to you to understand the picture !!!!!!!
:-))))))
Serge
_______________________________________
Thank you, Serge - You're a star!
Serge Brunier has kindly replied to my query, as follows;
__________________________________________
:-(((((((((((
Dear John,
I'm frustrated by your mail : I think to this picture nearly one year before
to go to Chile to take it...
My intention was to SHOW OUR MILKY WAY AS IT WAS SEEN FROM OUTSIDE, as a Galaxy.............
Unfortunately, the bosses of APOD seems to not understood !!!!!!!!!
Anyway, of course, I m very happy to have been published in APOD !!
The picture was taken in last June, in Atacama desert, were the galactic
center is just overhead at midnight, with a fisheye lens...
Thanks to you to understand the picture !!!!!!!
:-))))))
Serge
_______________________________________
Thank you, Serge - You're a star!
It is of a portion of a galaxy that is some 70,000 LY across and seen at a distance of approx ?25000 LY? our relative distance to the center.
http://antwrp.gsfc.nasa.gov/apod/ap051004.html
http://antwrp.gsfc.nasa.gov/apod/ap051004.html
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It is always a great satisfaction when a mystery is solved.
Our galaxy, the Milky Way, is beautiful in all it's wonders.
Imagine if you would, standing on a planet similar to earth, near the center of our galaxy.
What would the heavens look like at night?
Breath takingly beautiful, but bring your night shades.![Wink :wink:](./images/smilies/icon_wink.gif)
Our galaxy, the Milky Way, is beautiful in all it's wonders.
Imagine if you would, standing on a planet similar to earth, near the center of our galaxy.
What would the heavens look like at night?
Breath takingly beautiful, but bring your night shades.
![Wink :wink:](./images/smilies/icon_wink.gif)
"It's not what you know, or don't know, but what you know that isn't so that will hurt you." Will Rodgers 1938
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I think you would need to bring your high energy, gamma ray deflection pajamas also, near the center of the galaxy is a much more hostile environment. In another 5 to 10 years the Voyagers should be able to tell us what the sun's heliosphere is protecting our solar system from, (high-energy nebula winds), just a milder version of the stuff that increases exponentially as the galactic center is approached.
http://voyager.jpl.nasa.gov/
http://www.cnn.com/2005/TECH/space/10/1 ... index.html
http://voyager.jpl.nasa.gov/
http://www.cnn.com/2005/TECH/space/10/1 ... index.html
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Seems I should bring my Sun Block 2000 for night time strolls then.
Could an atmosphere be thick enough and yet clear enough to provide a view I wonder?
Brave little craft those Voyagers.
"He dwells in unapproachable light."
Just a side thought.
Norval
![Wink :wink:](./images/smilies/icon_wink.gif)
Could an atmosphere be thick enough and yet clear enough to provide a view I wonder?
Brave little craft those Voyagers.
"He dwells in unapproachable light."
Just a side thought.
Norval
"It's not what you know, or don't know, but what you know that isn't so that will hurt you." Will Rodgers 1938
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