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Fraser
2006-Nov-25, 01:51 AM
This is an image of galaxy NGC 1313, taken with the FORS instrument at the ESO's Very Large Telescope. It's classified as a starburst galaxy, because of the dense regions of furious star formation. NGC 1313 is relatively close to the Milky Way, located only 15 million light-years away. To say it's forming many new stars is an understatement; NGC 1313 has a rate of star formation 1000x faster than the Milky Way. Galaxies like this usually went through a recent collision with another galaxy, but astronomers can't find the culprit anywhere near.

Read the full blog entry (http://www.universetoday.com/2006/11/24/starburst-galaxy-ngc-1313/)

antoniseb
2006-Nov-25, 11:18 AM
This IS an interesting galaxy. I am interested in learning more about it as time moves forward. 1313 is an easy number to remember.

RUF
2006-Nov-25, 08:16 PM
Perhaps the "interacting galaxy" that caused the boom of star-formation is "behind" 1313, from our point-of-view. I also find is suspicious that the "centre" of he galaxy is "off-kilter". Maybe 1313 swallowed a halo globular cluster. The evidence sure seems to point to a collision of some type.

antoniseb
2006-Nov-25, 08:36 PM
It certainly seems possible that we are seeing a superposition of two interacting galaxies. I agree about the center of the galaxy being not in the bar seems *very* odd.

RussT
2006-Nov-25, 11:10 PM
It certainly seems possible that we are seeing a superposition of two interacting galaxies.

I agree that there is little to no doubt there is a collision happening here.

I wish they would have shown where the Xray sources actually were!

This may be a smallish beginning spiral galaxy, where the Bar (If it is a Bar) and the arms were just starting to form their normal star formation, and then a largish (Magellenic Cloud type) dwarf galaxy is colliding with it, obviously causing a huge starburst.

I say..."if it is a Bar" because Bars are usually much more "filled in", "Brighter", and the question is...is the Bright spot in the middle of the 'Bar' a MBH??? or a IMBH??? Because if that Bright spot is just a globular cluster with BH that 'fits' a GC, then that is probably not a Bar, and this could be 2 largish dwarf galaxies colliding.

Also, we would need to see a detailed HI data survey to determine more. For example, the upper arm (if it is an arm) at about 11 O'clock appears to be 'pulled' up as if there is some unseen gravitational entity.

I noticed something else very interesting. If you look to the right side iof the 'Bar' at 3 O'clock, just outside the bluish stars, just into the black, there is a distinct 'round' dark green object, with what appears to be a 'light source' shining on its 3 O'clock position???

antoniseb
2006-Nov-25, 11:34 PM
If you look to the right side iof the 'Bar' at 3 O'clock, just outside the bluish stars, just into the black, there is a distinct 'round' dark green object, with what appears to be a 'light source' shining on its 3 O'clock position???

There's another one at the ten oclock position, and a dimmer one to the right of the bright object at the six oclock position. The story says:

This image, obtained with ESOís Very Large Telescope, demonstrates once again how the imager FORS is ideally suited to capturing the beauty and stunning complexity of galaxies by observing them in different wavelength filters, combined here to form a stunning colour image.
which I take to mean these are not natural colors. It is likely that these 'green' blobs are Hydrogen Balmer red, because red in this image has been reserved for the near infrared.

joedoe
2006-Nov-26, 01:45 AM
Probing ever deeper into the heart of the galaxy, astronomers have revealed many enigmas that continue to defy our understanding.

:whistle:

As it will, to we modify our understanding :mad:


An explanation based on the presence of the central bar also does not hold for NGC 1313: the majority of its star formation is actually taking place not in its bar but in dense gassy regions scattered around the arms.
By what mechanism the gas is compressed for stars to form at this staggering rate, astronomers simply arenít sure.

Some are :doh: And why does the "dense gassy regions" (plasma/s) have to compress (under gravity??) to form a star?


In the midst of the cosmic violence of the starburst regions lie two objects that emit large amounts of highly energetic X-rays - so-called ultra-luminous X-ray sources (ULX).

Could be a clue, highly energetic X-rays. What process could, in nature, produce highly energetic X-rays? :eh:

So until we take into account "other" possibilities we will continue to be surprised :p

Time varying magnetic fields anyone? ;)

John Mendenhall
2006-Nov-27, 05:54 PM
:whistle:me are :doh:
So until we take into account "other" possibilities we will continue to be surprised :p

Time varying magnetic fields anyone? ;)

References? Links? I don't like dark matter / dark energy, but what I'm familiar with in electromagnetic solutions to cosmological problems has not impressed me.

(O.K., dm / de guys, you win a debating point on this one. In this case, I like your gravitational solutions better.)

Jerry
2006-Nov-30, 04:33 PM
Perhaps the "interacting galaxy" that caused the boom of star-formation is "behind" 1313, from our point-of-view. I also find is suspicious that the "centre" of he galaxy is "off-kilter". Maybe 1313 swallowed a halo globular cluster. The evidence sure seems to point to a collision of some type.Collision or not, what is compressing the gas the star forming regions? How can the apparent center of mass be so far removed from the rotational center? Very odd.