Tuesday, September 05, 2006

Twisting Space & Time

Credit: Joe Bergeron of Sky & Telescope magazine

An artist's impression of space and time
twisting around a spinning black hole.

Astronomers might have already observed the effects of gravitomagnetism. Some black holes and neutron stars shoot bright jets of matter into space at nearly light speed. These jets come in pairs, oppositely directed, as if they emerge from the poles of a rotating object. Theorists think the jets could be powered and collimated by gravitomagnetism

In addition, black holes are surrounded by disks of infalling matter called "accretion disks," so hot they glow in the x-ray region of the electromagnetic spectrum. There's mounting evidence, gathered by X-ray telescopes such as NASA's Chandra X-ray Observatory, that these disks wobble, much like the gyroscopes on Gravity Probe B are expected to do. Gravitomagnetism again? Perhaps

Here in our solar system gravitomagnetism is, at best, feeble. This raises the question, what do we do with gravitomagnetism once we've found it? The same question was posed, many times, in the 19th century when Maxwell, Faraday and others were exploring electromagnetism. What use could it be?

Today we're surrounded by the benefits of their research. Light bulbs. Computers. Washing machines. The Internet. The list goes on and on. What will gravitomagnetism be good for? Is it just "another milestone on the path of our natural quest to understand nature?" wonders Will. Or something unimaginably practical? Time will tell.

more on gravitomagnetism by Dr Tony Phillips @ first science
For more information visit
A Review of Gravity Probe B - from the National Research Council
Famous Quotes
Any sufficiently advanced technology
is indistinguishable from magic.
Arthur C. Clarke