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Black Hole Emits a 1,000-Light-Year-Wide Gas Bubble

Posted by Soulskill on from the reminds-me-of-a-buddy-of-mine dept.

PhrostyMcByte writes "12 million light-years away, in the outer spiral of galaxy NGC 7793, a bubble of hot gas approximately 1,000 light-years in diameter can be found shooting out of a black hole — one of the most powerful jets of energy ever seen. (Abstract available at Nature.) The bubble has been growing for approximately 200,000 years, and is expanding at around 1,000,000 kilometers per hour."

3 of 145 comments (clear)

  1. very minor issue by Lazareth · · Score: 5, Informative

    A minor issue with the headline (of both the summary and the article) is that the black hole does not really emit the gas bubble per se. It is emitting jets of extremely fast moving particles which then hits nearby interstella gas. Obviously this causes an increase in temperature, creating a "snowball" effect resulting in the aforementioned 1000-light-year-wide (flaming) gas bubble.

  2. Re:How can a black hole emit anything? by sexconker · · Score: 5, Informative

    They can emit Hawking radiation.

    Basically, pairs of particles appear out of nowhere for extremely brief amounts of time, fly around a bit, then collide together and disappear again.

    (Yes, this happens. Matter appears out of nowhere and then disappears again.)

    If this pair of particles pops into existence just outside the event horizon of a black hole, there's a chance that, in their brief flying about, one will cross the event horizon and the other will not. Since they're no disjoint, they don't disappear like they normally do.

    The particle that is on the outside of the event horizon escapes as Hawking radiation.

  3. Re:How can a black hole emit anything? by DragonWriter · · Score: 5, Informative

    I love how people talk about black holes like they know how they work.

    It always amazes me that both laymen and scientists as well talk about such things as if we KNOW whats going on.

    We don't. We have theories.

    In science, its important to remember that a "theory" is not the same thing as the loose definition of a theory in casual conversation, or some technical but non-scientific contexts (literary criticism, I'm looking at you.)

    In science, a theory is a hypothesis whose predictions which make it falsifiable have withstood testing and which remains viable. The casual-conversation concept of "theory" as an plausible but unverified idea about the world is what in science would be a conjecture or a hypothesis, not a theory.

    So, often, we talk about theories (as opposed to mere conjectures or hypotheses) as if they were known except in very particular contexts where there theoretical nature is particularly important (such as in the case of a conflict between two theories that have both withstood scrutiny but where the predictions each makes in conditions impractical to test conflict.) But there's a good reason for that: if it is a "theory" as the term is used in science, it has demonstrated it power in explaining behavior beyond that which was consulted to formulate it. It may need to be refined, but its known to be a useful model.