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Movie - Schwarze Löcher / Text Englisch

NARRATOR: The Chandra X-ray Observatory orbits high above the Earth, peering into the blackest reaches of space.

Exploring the most menacing and magnificent features of the cosmos, this remarkable telescope is revealing what our eyes can't, taking us beyond visible light.

The bad boys of astronomy, black holes inspire well-deserved wariness and strange fascination.

But what exactly are they?

Scientists harnessing the incredible power of Chandra have discovered that black holes play a critical role in both the development and demise of stars and galaxies.

While astronomers have long known that black holes existed, it wasn't until Chandra was launched in 1999 that some of their elusive secrets were revealed.

With its insightful perspective, Chandra has shed a revealing light on the dark mysteries of black holes.

Focusing on the deepest depths of space, Chandra has witnessed the gluttonous eating habits of some black holes.

DR. HARVEY TANANBAUM: And in those regions where the X-rays are deficient, where the gas voids exist, is the same regions where you see the radio lobes, these jets and lobes that are formed from the radios.

So you know that energetic particles are being shot away from the black hole by some kind of mysterious process, and they're clearing the gas away.

They're pushing the gas aside.

Because the gas has a density and a temperature, properties that we measure in the X-rays, it's very easy to calculate the amount of work that's needed to clear these voids.

So you can actually measure the energy that's carried out by these jets of particles.

NARRATOR: However, not all black holes mean certain doom for their neighbors.

Consider for example, one known as Sagittarius A Star, a black hole churning at the center of our own Milky Way galaxy.

Unlike its more malicious siblings, this black hole appears to be protecting a flock of young stars instead of eating them.

TANANBAUM: With Chandra, we're able to measure the density and temperature of the gas just outside the black hole at the center of the Milky Way galaxy, and there's plenty of gas there and it's hot!

And we should see, even with conservative theories, instead of 100 billion times the amount of radiation that we see, we should see a billion times or some 100 million times; it doesn't matter, it's a large factor greater than what we see.

NARRATOR: Equal parts stellar destroyers and cosmic creators, Chandra's black holes exhibit dual nature.

While some black holes voraciously devour gases and galaxies, others coddle them, proving yet again that bad boys usually have a good side.

Quelle:
http://www.nasa.gov/multimedia

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