Space

Is there a pulsar at the center of our galaxy?

No. A black hole is thought to lie at the very center of our galaxy. But there’s an object close by – G359.95-0.04, about a light-year from the center of our galaxy – that appears to be a pulsar.

A pulsar is a rapidly spinning dead star that’s smaller than a large city but more massive than our sun. Astronomers discovered this object only one light-year away from Sagittarius A, thought to be a black hole at the center of our Milky Way galaxy.

The galactic center is thought to be marked by a giant black hole, an object with such powerful gravity that nothing, not even light, can escape. All other objects in the Milky Way – including our sun and Earth -revolve around the center of the galaxy. Closer to the galactic center, millions of stars swirl around the the galaxy’s central black hole, like bees around a honeycomb.

Now astronomers have discovered what looks like a pulsar that’s only about one light-year from this black hole. A pulsar is a rapidly spinning dead star. Like a lighthouse, a pulsar emits radiation in a beam, so that astronomers detect a pulse of radiation with each spin of the pulsar.

Astronomers often say that pulsars serve as accurate clocks. That’s because a typical pulsar keeps spinning at precisely the same rate for a long time. So, astronomers can use pulsars to monitor the flow of time. And that means the newly discovered pulsar might help scientists test Einstein’s general theory of relativity, which manifests itself most in regions of strong gravity.

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Posted 
September 23, 2009
 in 
Space

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