Black Hole Bullies Neighboring Stars NASA observatories have discovered a fight brewing in a galaxy far, far away. It seems a black hole is pummeling a small, nearby star cluster with a jet of highly charged radiation.
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Black Hole Bullies Neighboring Stars

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Black Hole Bullies Neighboring Stars

Black Hole Bullies Neighboring Stars

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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You have to admit, when you see the headline, NASA announces discovery of assault by a black hole, it gets your attention. It got ours. The assault in question is taking place between two galaxies far, far away. How far?

Mr. DANIEL EVANS (Harvard-Smithsonian Center for Astrophysics): 1.4 billion light years.

BLOCK: A bigger galaxy is bombarding a smaller galaxy. They're collectively named…

Mr. EVANS: 3C 321.

BLOCK: Okay. The bigger galaxy is bombarding the smaller one with a powerful jet of radiation. It is, astronomers say, an act of never-before-witnessed galactic violence.

And here to tell us more about this space abuse is astrophysicist Daniel Evans of the Harvard-Smithsonian Center for Astrophysics. Thanks for being with us.

Mr. EVANS: Well, you're very welcome. Thank you.

BLOCK: I have to say, based on the images I've seen on the Web, an act of violence it may be, but it is a beautiful thing.

Mr. EVANS: It really is. One of the main reasons I got involved with astronomy and astrophysics research is just by the staggering beauty of the images that we see. My particular research places a very strong emphasis on combining images across the electromagnetic spectrum. So the image you've seen on the Web really ties together images from the radio wavelengths, from the optical wavelengths, all the way up to the very powerful X-rays, and then it produces a really striking image.

BLOCK: Why don't you describe that image?

Mr. EVANS: What we're looking at, as you said, is a really extraordinary act of violence by a black hole. We can see that a very powerful jet of particles is being ejected from a supermassive black hole in the center of a distant galaxy. And there's an unfortunate neighboring galaxy, as you say, has moved directly into its line of fire. And so, not only does this cause the jet to be significantly disruptive, but it may actually have disastrous consequences for any Earthlike planets that happen to lie in its path.

BLOCK: Mm-hmm. So pretty bad news for that smaller galaxy, but I gather there could be an upside to this destructive power of the bigger galaxy?

Mr. EVANS: That's absolutely right. So although we calculated that currently, this jet is probably destroying anything in its path, the ultimate legacy of this interaction can actually be that the jet is compressing clouds of gas. And it's that compression of these gas clouds that leads to the formation of stars and the formations of new planets. So the long-shot legacy could be that it's actually a provider and a generator of life as well as a destroyer.

BLOCK: How long has this been going on?

Mr. EVANS: So in astronomical terms, this is only a very recent interaction. Although this thing lies at a distance of 1.4 billion light years from us, we're witnessing an interaction that has only being taking place for one million plus that 1.4 billion light years.


Mr. EVANS: Does that make sense?

BLOCK: And, well, I think so. But in space terms, that's pretty recent, in other words.

Mr. EVANS: One million light years, with respect to the age of the overall galaxy which is probably in the excess of, I don't know, a hundred million to a billion years, this really is peanuts. So by witnessing this interaction, we're probably looking at it at a pretty special time. And therefore, it's a unique opportunity for us to study the way these jets interact and inject energy into their environments. And therefore, we can understand some things about the universe when we witness this.

BLOCK: For purely selfish reasons for those of us in our nice little galaxy, would there be anything in what you're learning that would indicate that we could be headed toward a similar fate with some black hole in a neighboring galaxy deciding to beat up on us?

Mr. EVANS: Well, no. Or should I say not yet? I think the idea is that the majority of galaxies that lie around our Milky Way in our local group, including our Milky Way itself, have pretty dormant black holes. They're not doing very much and they're certainly not ejecting these powerful jets. So I wouldn't worry about it too much yet.

BLOCK: Well, that's very reassuring; that's the best news I've heard all day.

Mr. EVANS: Well, I'm glad to hear it.

(Soundbite of laughter)

BLOCK: Well, Daniel Evans, it's good to talk to you. Thanks so much.

Mr. EVANS: Thank you very much.

BLOCK: Daniel Evans of the Harvard-Smithsonian Center for Astrophysics. He is the leader of the study whose real title, when it's published in the astrophysical journal in March will, I'm sure, be far less interesting than "Death Star Galaxy Beats Up Its Neighbor."

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