Solar sail test could prove space-time theory

[captdude]

Here is an interesting article on testing frame-dragging. The first two paragraphs have been cut and pasted below the link to the full article.


http://www.msnbc.msn.com/id/38420472/ns/technology_and_science-space

by Stuart Fox

updated 7/26/2010 7:08:23 PM ET
Solar sails that use sunlight pressure instead of fuel to fly through space have long been touted by space exploration advocates, but the novel space travel method could also be tapped to settle an unproven theory by famed scientist Albert Einstein.

A gossamer solar sail would be a prime platform for an experiment that would test the so-called frame-dragging hypothesis in Einstein's General Theory of Relativity, said Roman Kezerashvili, a professor of physics at New York City College of Technology. He presented the experiment concept during the International Symposium on Solar Sailing held here July 21 at the college.

 

[undidly]

http://www.msnbc.msn.com/id/38420472/ns ... ence-space is poorly written.

""Frame dragging is an effect where massive spinning bodies distort the fabric of space time like a whirlpool in water.""

No it is not.
ALL mass distorts the fabric of space time.
A spinning mass DRAGS the fabric of space time.
That is why is is called frame DRAGGING.
The writer misses the point.
Such sloppy writing.
Sack the writer.

 

[Astro_Robert]

The reporter should have read up on Gravity Probe B before stating that Frame Dragging has never been proven.

The effect may have been small, but the team did report some results in that regard.

 

[captdude]

The writers analogy may be flawed but I thought it was an interesting, low tech & low cost way to test an unproven theory.

 

[unclefred]

http://www.msnbc.msn.com/id/38420472/ns/technology_and_science-space is poorly written.

""Frame dragging is an effect where massive spinning bodies distort the fabric of space time like a whirlpool in water.""

No it is not.
ALL mass distorts the fabric of space time.
A spinning mass DRAGS the fabric of space time.
That is why is is called frame DRAGGING.
The writer misses the point.
Such sloppy writing.
Sack the writer.

According to my dictionary, a whirlpool is a rotating mass of water. The example given is the water going down a drain does not flow evenly or straight down, but rotates or spins as it is drawn in. Is not that what frame dragging is? Consider two equal massive bodies, one spinning and one not. They both would provide the same gravitational pull (i.e. the same distortion of the fabric of space time). However, the spinning mass may cause the fabric of space time to also be drug around with the mass. If true, this would cause an object to not fall directly into the mass but would have a spin or rotational component. Exactly like a whirlpool.
My question is: How is the solar sail spacecraft any better at detecting this phenomena than any other spacecraft? Since the sun is constantly pushing on it, it would seem to me that any deviation in its path could be due to variations in the sun's push. One now has to measure and compensate for an changes in the solar sail's geometry or it's absorption/reflection properties. It would seem to me, that it would be better to use a normal spacecraft that does not have these variables to contend with.