Einstein was right, space and time bend.

Almost a century after Einstein made his famous remarks about the relationship between space, time and the speed of light, an expensive (US$700million) NASA probe seeminly proved that the universe worked the way Einstein predicted it would. (Although the rest sill hasn't been proven).
From: The Observer

The early results from Gravity Probe B, one of Nasa's most complicated satellites, confirmed yesterday (Saturday 14th of April) 'to a precision of better than 1 per cent' that any object with a mass will disturb space and time.

But this - what is referred to as the 'geodetic' effect - is only half of the theory. The other, 'frame-dragging', stated that as the world spins it drags the fabric of the universe behind it.

Francis Everitt, the Stanford University professor who has devoted his life to investigating Einstein's theory of relativity, told scientists at the American Physical Society it would be another eight months before he could measure the 'frame-dragging' effect precisely.

'Understanding the details is a bit like an archeological dig,' said William Bencze, programme manager for the mission. 'A scientist starts with a bulldozer, follows with a shovel, then finally uses dental picks and toothbrushes to clear the dust away. We're passing out the toothbrushes now.'

The Gravity Probe B project was conceived in the late 1950s but suffered decades of delays while other scientists ran tests corroborating Einstein's theory. It was Everitt's determination that stopped it being cancelled. The joint mission between Nasa and Stanford University uses four of the most perfect spheres - ultra precise gyroscopes - to detect minute distortions in the fabric of the universe. Everitt's aim was to prove to the highest precision yet if Einstein was correct in the way he described gravity.

According to Einstein, in the same way that a large ball placed on a elasticated cloth stretches the fabric and causes it to sag, so planets and stars warp space-time. A marble moving along the sagging cloth will be drawn towards the ball, as the Earth is to the Sun, but not fall into it as long as it keeps moving at speed. Gravity, argued Einstein, was not an attractive force between bodies as had been previously thought.

The theory explained

When Einstein wrote his general theory of relativity in 1915, he found a new way to describe gravity. It was not a force, as Sir Isaac Newton had supposed, but a consequence of the distortion of space and time, conceived together in his theory as 'space-time'. Any object distorts the fabric of space-time and the bigger it is, the greater the effect.

Just as a bowling ball placed on a trampoline stretches the fabric and causes it to sag, so planets and stars warp space-time - a phenomenon known as the 'geodetic effect'. A marble moving along the trampoline will be drawn inexorably towards the ball.

Thus the planets orbiting the Sun are not being pulled by the Sun; they are following the curved space-time deformation caused by the Sun. The reason the planets never fall into the Sun is because of the speed at which they are travelling.

According to the theory, matter and energy distort space-time, curving it around themselves. 'Frame dragging' theoretically occurs when the rotation of a large body 'twists' nearby space and time. It is this second part of Einstein's theory that the Nasa mission has yet to corroborate.

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Useful links
Nasa homepage
Nasa Watch (not a Nasa site)
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Space.com
The Planetary Society
Houston Space Chronicle
Encyclopedia Astronautica
Nasa Human Spaceflight (shuttle homepage)
Kennedy Space Center
European Space Agency
United Nations Office for Outer Space Affairs
British National Space Centre
Search for Extraterrestrial Intelligence (SETI)