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Hubble’s Magnetic Monster

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The Power of Magnetic Fields in Space

Yesterday this amazing picture came rumbling through the Intarwebs from the folks at Hubble Space Telescope. It’s from the Advanced Camera for Surveys and shows the galaxy NGC 1275 seemingly surrounded by what looks like a spiderweb of stuff.

Now, there’s a lot going on here, so let’s break it down. First, the galaxy is in the center of the Perseus Cluster of galaxies, and the whole region is permeated with hot gas — REALLY hot — around 100 million degrees. The red stringy things are filaments of cooler hydrogen gas and they’re threaded on magnetic field lines that extend throughout the region.

Magnetic field lines?  Yes, this is indeed true. The actions of a supermassive black hole and its associated jet at the core of the galaxy are the source of very strong magnetic fields that extend quite far out from the core. Gas near the center of the galaxy gets superheated by all the hoopla surrounding the black hole and jet, and that blows bubbles of material out into surrounding space. Those expanding bubbles plow into cooler regions of hydrogen gas, and the expansion carries some of that gas out along with it. The red filaments are the hydrogen gas that looks like it’s draped on the magnetic field lines. Those filaments are actually a very important clue to astronomers. They are the biggest visible-light evidence for some “invisible” (i.e. not visible to our eyes) interactions between NGC 1275’s central black hole and the hot gas that permeates the surrounding interstellar and intergalactic spaces.

Now, the filaments look really delicate, and you’d think that the huffing and puffing of material blasting out from the center of the galaxy via the jet would destroy the hydrogen gas threads. What’s saving them are the magnetic fields. Those lines of force hold the gas in place and help it resist the outward blasts from the core of the galaxy. They also keep the gas from clumping up to form newborn stars, making them a disruptive as well as a unifying force.

For anybody who thought that intergalactic space might be empty and boring, this image and another one taken with multiple instruments (left), reveals just how frenetic the environment in galaxy clusters can be.

While we may not be able to see those magnetic fields, images like these show us the effects that such fields have on the ordinary matter they thread through.

For more information, surf on over to the Space Telescope Science Institute’s HubbleSite page.

black holes

Black Holes Get No Respect

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They’re SO Misunderstood

How many of you have seen ANY movie or read a bad science fiction story that featured a black hole that had people somehow flying into a black hole and managing to get out again? I remember this really awful movie from Disney called (imaginatively enough) “The Black Hole” that pretty much ignored most physical laws and violated more than a few storytelling rules. It seems like black holes suck more than gas and dust and stars into their maws. They also have the strange ability to remove a writer’s common sense when it comes to a) tellling a credible story, and b) respecting that black holes have rules they must follow and that you can’t bend those rules just so that the hero can get the girl in the end.

Let’s face it. If you’re in a spacecraft anywhere NEAR a black hole, you’re going to feel its effects. Its gravitational pull will tug at you. The radiation environment will kill you, unless your spacecraft is really well-shielded. And even then, there’s a good chance that you’re never going to father (or mother) children after the encounter (provided you survive it). If you happen to stray too close to the black hole, you’re toast. You’re going in and you’re going to be swirling down the celestial tidy bowl for a LONG time (from the perspective of an outside observer). From YOUR perspective, it’s going to be a short, nasty, brutish trip into the universe’s ultimate trash compactor. And, no matter how much a producer or writer or art director or second assistant key grip wants to see your spacecraft escape the black hole, it ain’t gonna happen. You won’t have a droid up there in the control booth trying to turn off the compactor at the last second. You. Are. Toast.

So, you might ask me if you’re one of those writers who just HAS to have a black hole in your show to keep the sponsors happy, what CAN be written about? IS there a viable, exciting story about these things that could hold an audience’s interest?

Of course I have an answer to that, mostly because I DID write such a story some years ago for a planetarium show. I had the spacecraft go not quite close enough to the singularity’s event horizon and the pilot pulled out just in time… but not before a few hair-raising, nail-biting moments when both the crew and the audience weren’t sure if they’d get out in time. I had twenty minutes to get them out TO the black hole’s vicinity (all the while explaining how we can detect these dudes), and then about five minutes to put them in danger and get them out again. By standards of a movie or network TV, that’s pretty short, but it kept me intellectually honest, and I told a good story with accurate science and emotional affect (as they like to say in the business).

So, it can be done. And black holes, if you respect them and what they’re about, can give you fodder for a LOT of good stories.