Coal sack nebula

[PB666]

http://www.eso.org/public/news/eso1539/

How is this dust going to ignite?

[Dkmdlb]

Gravity will pull it all together and it will go nuclear.

[The_Rocketeer]

God has a special set of cosmic firelighters for when the bbq won't take.

[PB666]

Gravity will pull it all together and it will go nuclear.

i was responding to this 'nugget'

and the coal “nuggets†in the Coalsack will "combust", almost as if touched by a flame.

Ok but they are talking about the cause of the light scattering as being large amount of ice, carbon, and frozen nitrogen. These elements are not the favored materials of stars. Stars that start out burning lots of carbon tend to go poof.

[p1t1o]

The choice of name for that particular object probably puts an image in most peoples heads that over-exaggerates the proportion of carbon in the nebula, its likely that there is a significant amount of more standard star-stuff in amongst it all. You'll probably find most nebulae contain a lot of "dust", the dust in this one is just particularly dark.

Fun fact:

What is the blackest object in the solar system?

The Sun. No joke, the suns colour, if it was not washed out by its blackbody radiation, is deepest black.

[PB666]

If the sun did not produce blackbody radiation everything in the solar system would be black. Lets think about that, imagine if the sun had all its energy zapped out of it, the layers would separate, the would be a ocean of hydrogen, followed by helium, oxygen and carbon, the core would collapse, and it would nova, becoming the brightest object in this part of the galaxy.

It not just a little taint of carbon, it has so much carbon that it absorbs or scatters most of the 'transmitted' light.

[p1t1o]

If the sun did not produce blackbody radiation everything in the solar system would be black. Lets think about that, imagine if the sun had all its energy zapped out of it, the layers would separate, the would be a ocean of hydrogen, followed by helium, oxygen and carbon, the core would collapse, and it would nova, becoming the brightest object in this part of the galaxy.

It not just a little taint of carbon, it has so much carbon that it absorbs or scatters most of the 'transmitted' light.

Well no, green stuff is still green even if you dont shine light on it. The point is the sun reflect almost no [visible] light whatsoever, it is blacker than soot.

As far as I know, the coalsack nebula does not necessarily have more carbon than the next nebula, the article implies that it is the coatings on the particles consisting of frozen water, nitrogen and some simple organics that are responsible for its higher than usual light absorption, the particle density also contributes, along with the fact that it is not being irradiated by any nearby UV sources or similar. I don't see anything to suggest that it is any closer to a cloud of soot than any other nebula.

[PB666]

Well no, green stuff is still green even if you dont shine light on it. The point is the sun reflect almost no [visible] light whatsoever, it is blacker than soot.

As far as I know, the coalsack nebula does not necessarily have more carbon than the next nebula, the article implies that it is the coatings on the particles consisting of frozen water, nitrogen and some simple organics that are responsible for its higher than usual light absorption, the particle density also contributes, along with the fact that it is not being irradiated by any nearby UV sources or similar. I don't see anything to suggest that it is any closer to a cloud of soot than any other nebula.

Its only a few 1000 ly away lets test this, need a warp drive a probe with ability to warp space, several, a subspace communicator...........a few space aliens for drama......and of course a global warning because making a supernova may not be a good thing, and those space aliens may hate us for thrashing their area of space.

[p1t1o]

Just let slip to the US that you could mine it for oil and we'll be there by 2016. LULZARAMA!

[cantab]

Well no, green stuff is still green even if you dont shine light on it. The point is the sun reflect almost no [visible] light whatsoever, it is blacker than soot.

This is being silly. If I have an LED that emits red light but is black when not emitting light, I am still going to say it's red when it's lit.

[PB666]

This is being silly. If I have an LED that emits red light but is black when not emitting light, I am still going to say it's red when it's lit.

No, its the sun when its lit.

[p1t1o]

This is being silly. If I have an LED that emits red light but is black when not emitting light, I am still going to say it's red when it's lit.

Well of course. In this context "blackness" is being used as a physical property, I presented it as a "fun fact" because the layperson wouldn't expect that the suns natural colour is so dark.

[YNM]

@p1t1o : (Off Topic) The actual "color" of Sun-material would be just a few lines in the red and blue end of visible spectrum. The Sun itself actually contains a mechanism (process) that produces gamma rays - just that collisions with other parricle on the way out causes the surface to glow yellow.

Your joke is just the same with the fact that, while you can see with your eye+brain, your brain is in eternal darkness until someone rip it open.

--------

On Topic : Well, the author of the article didn't want to explain/mention that each gas particle are gravitationally bounded to each other in the "nebula", and they'll be moving closer to each other out of differences in potential energy, gaining kinetic energy, slamming whatever there is at the "center", and when the slamming is hard enough (or they have vibrated enough after the slamming), fusion happens in the core. And you got a star. Young stars are dangerous - they can spit back on you !

[problemecium]

The article is just using unscientific language. As we all should know, in the absence of anything but tiny traces of oxygen, nothing can burn in the conventional sense.

What I think they meant was that as the stars become luminous (and begin a process many casually describe as "burning"), their light will make the nebula look as if the Coal in its Sack has caught fire.

Also, the Sun doesn't really have any light to be reflecting. Earth would be black, too, if it were in interstellar space. Stars should, theoretically, reflect light from more luminous companions, so if you stuck a class B, for example, right next to the Sun, the Sun would be seen (through an appropriately strong dimming filter) to reflect the blue light on one side.

Edited October 16, 2015 by parameciumkid