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Our Galaxy's Magnetic Field from Planck

Explanation: What does the magnetic field of our Galaxy look like? It has long been known that a modest magnetic field pervades our Milky Way Galaxy because it is seen to align small dust grains that scatter background light. Only recently, however, has the Sun-orbiting Planck satellite made a high-resolution map of this field. Color coded, the 30-degree wide map confirms, among other things, that the Galaxy's interstellar magnetism is strongest in the central disk. The revolution of charged gas around the Galactic center creates this magnetism, and it is hypothesized that viewed from the top, the Milky Way's magnetic field would appear as a spiral swirling out from the center. What caused many of the details in this and similar Planck maps -- and how magnetism in general affected our Galaxy's evolution -- will likely remain topics of research for years to come.

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Planck is not Earth-Orbiting, it's Sun-Orbiting near L2. Please correct this.

ekkehart wrote:Planck is not Earth-Orbiting, it's Sun-Orbiting near L2. Please correct this.

It's no more a Sun orbit than it is an Earth orbit. I think it would be more appropriate to call it a Sun-Earth L2 orbit. The description is definitely wrong, though.

Small Magellanic cloud seems to be affected by the magnetic field, but Large seems to be way out of it?

When I first saw this image, I was reminded of Jupiter!

It is now known that the interstellar magnetic field also has an effect on planetary nebulae! See here and here.

ekkehart wrote:Planck is not Earth-Orbiting, it's Sun-Orbiting near L2. Please correct this.

Yes thank you. This has now been corrected. - RJN

geckzilla wrote:

ekkehart wrote:Planck is not Earth-Orbiting, it's Sun-Orbiting near L2. Please correct this.

It's no more a Sun orbit than it is an Earth orbit. I think it would be more appropriate to call it a Sun-Earth L2 orbit. The description is definitely wrong, though.

It's actually in a complex orbit around the Sun-Earth L2 point, which itself is reasonably considered Sun-orbiting (although only in a sense).

So... the spirit of Vincent van Gogh is inhabiting the Planck imager...?

Stunning image just visually, and I'm sure that the data about the structure of the galaxy is equally rich.

No wonder I can't find North!!!
I too thought it was a Van Gogh, for a minute...maybe the guy wasn't too far off?

I wonder what effect the Galactic Magnetic Field, GMF, has on US....in our position in the galaxy, if any...does it have an effect on the N/S alignment of planets and the Sun...like with regular magnets? Or is it way too diffuse, and weak to have any effect?

I think we need a Planck image of the Universe...UMF might be interesting, and affect structure???

Science is sooooo amazing!!!

:---[===] ^

Chris Peterson wrote:

geckzilla wrote:

ekkehart wrote:Planck is not Earth-Orbiting, it's Sun-Orbiting near L2. Please correct this.

It's no more a Sun orbit than it is an Earth orbit. I think it would be more appropriate to call it a Sun-Earth L2 orbit. The description is definitely wrong, though.

It's actually in a complex orbit around the Sun-Earth L2 point, which itself is reasonably considered Sun-orbiting (although only in a sense).

Reminds me of Rosetta's early orbit around 67P which was more of a series of trajectories which had to be altered repeatedly to keep it from flying away. People saw the videos and questioned the use of the word "orbit" then but it's less obvious for an L2 orbit. Looks like it's going around the Sun.

FYI, based on an informative and helpful email, I have just now changed the word "rotation" to "revolution". I apologize for the oversight.
- RJN

Chris Peterson wrote:

geckzilla wrote:

ekkehart wrote:Planck is not Earth-Orbiting, it's Sun-Orbiting near L2. Please correct this.

It's no more a Sun orbit than it is an Earth orbit. I think it would be more appropriate to call it a Sun-Earth L2 orbit. The description is definitely wrong, though.

It's actually in a complex orbit around the Sun-Earth L2 point, which itself is reasonably considered Sun-orbiting (although only in a sense).

Thinking loosely and geocentrically, I suppose one could also say that Planck orbits Earth once per year, just like Sol orbits Earth once per year.

Boomer12k wrote:I wonder what effect the Galactic Magnetic Field, GMF, has on US....in our position in the galaxy, if any...does it have an effect on the N/S alignment of planets and the Sun...like with regular magnets? Or is it way too diffuse, and weak to have any effect?

No evidence of any effect at all. It's just too small compared with other forces we experience.

Small Object. just above center left seems to hugely alter the field contours, while other larger objects to the right seem invisible to the field. Odd?

http://www.slate.com/blogs/bad_astronom ... _2004.html
Would a magnetar's magnetic field be detectable in this type of a map? Their powerful magnetic field is pretty intense but I don't know how far it would emanate from the neutron star to potentially be noticeable in a view of this size.
http://en.wikipedia.org/wiki/Magnetar

Ron-Astro Pharmacist wrote:http://www.slate.com/blogs/bad_astronom ... _2004.html
Would a magnetar's magnetic field be detectable in this type of a map? Their powerful magnetic field is pretty intense but I don't know how far it would emanate from the neutron star to potentially be noticeable in a view of this size.
http://en.wikipedia.org/wiki/Magnetar

I don't think so. Keep in mind that Planck didn't detect magnetic fields, but rather, very far-IR and microwave photons. Today's image shows blackbody emission from galactic dust, thus tracing the location of that dust. The observed structure is reasonably assumed to be caused by interaction with the galactic magnetic field. We're talking about instruments with resolutions from about 5-50 arcminutes. I'd assume this to be insufficient to detect any subtle effect of a single magnetar on surrounding interstellar dust. The inverse-square law means that any point magnetic body will necessarily have a field that is very local in nature.

Chris Peterson wrote:

Ron-Astro Pharmacist wrote:http://www.slate.com/blogs/bad_astronom ... _2004.html
Would a magnetar's magnetic field be detectable in this type of a map? Their powerful magnetic field is pretty intense but I don't know how far it would emanate from the neutron star to potentially be noticeable in a view of this size.
http://en.wikipedia.org/wiki/Magnetar

I don't think so. Keep in mind that Planck didn't detect magnetic fields, but rather, very far-IR and microwave photons. Today's image shows blackbody emission from galactic dust, thus tracing the location of that dust. The observed structure is reasonably assumed to be caused by interaction with the galactic magnetic field. We're talking about instruments with resolutions from about 5-50 arcminutes. I'd assume this to be insufficient to detect any subtle effect of a single magnetar on surrounding interstellar dust. The inverse-square law means that any point magnetic body will necessarily have a field that is very local in nature.

Thanks Chris. That got me thinking about interacting magnetars. A (+) pole to ( -) pole interaction would be quite the strong linkage and the opposite would be quite a repulsion. I don't think I've ever seen that described – not that it would be likely. I does seem likely that any charged particle in the area would be under the influence.

Ron-Astro Pharmacist wrote:Thanks Chris. That got me thinking about interacting magnetars. A (+) pole to ( -) pole interaction would be quite the strong linkage and the opposite would be quite a repulsion. I don't think I've ever seen that described – not that it would be likely. I does seem likely that any charged particle in the area would be under the influence. :?:

You'd need a pair of magnetars in the same stellar system. That does seem improbable.

Chris Peterson wrote:You'd need a pair of magnetars in the same stellar system. That does seem improbable.

If about 1 in 10 supernovae of the right size would produce a magnetar, then if there were a star-cluster with a lot of large stars formed around the same time, that burned out near the same time, it seems like that might be a place for more than one to occur. But if a magnetar is only active for about 10,000 years, it does seem very hard to get two to pop up near each other.

MarkBour wrote:

Chris Peterson wrote:You'd need a pair of magnetars in the same stellar system. That does seem improbable.

If about 1 in 10 supernovae of the right size would produce a magnetar, then if there were a star-cluster with a lot of large stars formed around the same time, that burned out near the same time, it seems like that might be a place for more than one to occur. But if a magnetar is only active for about 10,000 years, it does seem very hard to get two to pop up near each other.

Not just near. Literally in the same system. Even a light year apart would be too far for their magnetic interaction to be significant.

I think I've seen this image before. Maybe Van Gogh?

Remo wrote:I think I've seen this image before. Maybe Van Gogh?
http://upload.wikimedia.org/wikipedia/c ... lance1.jpg

Yep. Just look at the filename. That painting is exactly what came to mind when I saw this image. From the Wikipedia article, there's an eerily relevant quote: Van Gogh threw himself into the painting of the stars, producing, they write, "a night sky unlike any other the world had ever seen with ordinary eyes."