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Comment by ardy42 | Hacker News Reader

Can someone give a quick explanation of the objects the picture? Are all the nebulas in the LMC or in the foreground? Is the LMC the reddish haze in the backround?

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The nebula are regions where stars are forming in the LMC. In fact, the brightest and largest on the middle left, is the Tarantula Nebula, with the young forming star cluster 30 Doradus. 30 Dor is notable for being the biggest, baddest star forming region in the Milky Way or its satellites--it hosts a few hundred stars more massive than sixty times the mass of the sun in it's core, and hosts the candidates for the highest mass stars observed, above around 150 solar masses. If placed 100 times closer to be where the Orion Nebula is, its illumination would cast visible shadows, taking up a quarter of the night sky with a surface brightness on average that of Venus.

How long will 150-solar-mass stars last?

As far as my knowledge goes, it's unknown, we have nothing to compare this star against (and it might go as high as 380 solar masses, we don't know).

It'll likely spend a few million years burning hydrogen before going to helium and heavier elements for a few thousand years.

A black hole is almost inevitable.

It's not quite your question, but here's a cool site that put its location in space in context for me: http://www.atlasoftheuniverse.com/sattelit.html

The LMC is effectively a galaxy that we captured and started tearing stars from. The white disk is the core.

Are the cloudy puffs remnants of exploded stars?

Some of them, yes.

We?

Your mass, and mine, are parties to the gravitational conspiracy, yes. One can even trivially prove that the Freemasons and the Roman Catholic Church are in on it. "We" is an appropriate pronoun in this instance, just as it would be for a nation of which you are a citizen.

The LMC is 160k light years away; 100 years ago 'we' didn't exist, the constituent matter that form us was there, but 'we'. Perhaps the twinkle in the eye, but no 'we' yet.

Since information and gravity movement is limited by the speed of light the effect of 'we' is by our age, so to a 100 light years for all but a very few people.

Also by that count all matter in the universe interacts with all other matter in the universe (OK out to the limit of the CMB).

So I am hedging my bets by saying it's wrong, or that it's so obvious its redundant.

In this case, the "we" was a stand-in pronoun for the Milky Way galaxy, of which we are part. It would have been linguistically tortuous to have phrased it in any other way; "we" was the appropriate pronoun, no matter how much it may embarrass you to be implicated in the action. Natural languages are not instances or implementations of propositional calculus.

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