Posted on 12/06/2005 11:34:47 PM PST by jb6
Huntsville AL (SPX) Nov 17, 2005 We'll soon know the answer: A NASA/Stanford physics experiment called Gravity Probe B (GP-B) recently finished a year of gathering science data in Earth orbit. The results, which will take another year to analyze, should reveal the shape of space-time around Earth--and, possibly, the vortex. Time and space, according to Einstein's theories of relativity, are woven together, forming a four-dimensional fabric called "space-time." The tremendous mass of Earth dimples this fabric, much like a heavy person sitting in the middle of a trampoline. Gravity, says Einstein, is simply the motion of objects following the curvaceous lines of the dimple.
If Earth were stationary, that would be the end of the story. But Earth is not stationary. Our planet spins, and the spin should twist the dimple, slightly, pulling it around into a 4-dimensional swirl. This is what GP-B went to space to check
The idea behind the experiment is simple:
Put a spinning gyroscope into orbit around the Earth, with the spin axis pointed toward some distant star as a fixed reference point. Free from external forces, the gyroscope's axis should continue pointing at the star--forever. But if space is twisted, the direction of the gyroscope's axis should drift over time. By noting this change in direction relative to the star, the twists of space-time could be measured.
In practice, the experiment is tremendously difficult.
The four gyroscopes in GP-B are the most perfect spheres ever made by humans. These ping pong-sized balls of fused quartz and silicon are 1.5 inches across and never vary from a perfect sphere by more than 40 atomic layers. If the gyroscopes weren't so spherical, their spin axes would wobble even without the effects of relativity.
According to calculations, the twisted space-time around Earth should cause the axes of the gyros to drift merely 0.041 arcseconds over a year. An arcsecond is 1/3600th of a degree. To measure this angle reasonably well, GP-B needed a fantastic precision of 0.0005 arcseconds. It's like measuring the thickness of a sheet of paper held edge-on 100 miles away.
GP-B researchers invented whole new technologies to make this possible. They developed a "drag free" satellite that could brush against the outer layers of Earth's atmosphere without disturbing the gyros. They figured out how to keep Earth's penetrating magnetic field out of the spacecraft. And they concocted a device to measure the spin of a gyro--without touching the gyro.
Pulling off the experiment was an exceptional challenge. A lot of time and money was on the line, but the GP-B scientists appear to have done it.
"There were not any major surprises" in the experiment's performance, says physics professor Francis Everitt, the Principal Investigator for GP-B at Stanford University. Now that data-taking is complete, he says the mood among the GP-B scientists is "a lot of enthusiasm, and a realization also that a lot of grinding hard work is ahead of us."
A careful, thorough analysis of the data is underway. The scientists will do it in three stages, Everitt explains. First, they will look at the data from each day of the year-long experiment, checking for irregularities. Next they'll break the data into roughly month-long chunks, and finally they'll look at the whole year. By doing it this way, the scientists should be able to find any problems that a more simple analysis might miss.
Eventually scientists around the world will scrutinize the data. Says Everitt, "we want our sternest critics to be us."
The stakes are high. If they detect the vortex, precisely as expected, it simply means that Einstein was right, again. But what if they don't? There might be a flaw in Einstein's theory, a tiny discrepancy that heralds a revolution in physics.
First, though, there are a lot of data to analyze. Stay tuned.
The Brits got it right from time to time, too.
Purple pageboy haircuts/silver metallic uniforms. Yummmmmm.
Yes, particularly the dimples... |
All I want to know is: Does this Put us any closer to the development of Warp Drive?
It's great to see our heart is always in the right place.
23 posts before the fawning stops. Thank you. This is a waste of taxpayer dollars. But Republicans don't care. Conservatism is dead among the party faithful
Consider for a momement that ultimately all science of any import is co-opted by the military, regardless of its specific field. It could searching for long-lost butterflies in the jungle, but if a certain chemical compound is detected that has 1000x the strength of existing polymers, it will investigated. A research project of this nature was probably funded from the DoD from the get-go; who knows what type of weapons/targeting refinements are going to be discovered.
Oh yes. Lord knows determining whether or not this planet is in some sort of vortex will have military value. Maybe we better check the space/time around the moon and Mars. Who knows when the Chinese or Russians could use that against us right?
It could searching for long-lost butterflies in the jungle, but if a certain chemical compound is detected that has 1000x the strength of existing polymers, it will investigated. A research project of this nature was probably funded from the DoD from the get-go; who knows what type of weapons/targeting refinements are going to be discovered.
I see. So we should all be glad our taxpayer dollars are being wasted solely on the possibility it will advance the military complex? Why? Because we're at war? Why don't we just nationalize all scientific research eh? Then we can just move on to other industries....Contrary to warped 'conservative' belief systems, the main intent of scientific research and discovery is not to forward the state.
"Seriesly, they need to bring back that whole Sci-Fi genre (complete with omnipresent pseudo-computer-cascading-light-panels in the background):"
They always pointed to a couple of spinning tape drives and said "this is the computer".
Ummm...Butt Dimples...
Man, that was a good show, Martin.
I'd forgotten about her! Got all hung up on Eartha Kitt & Julie Newmar.
Vefification of the "frame-dragging" effect helps in the proof of the Theory of Relativity.
When they originally started this project they had no idea the precision they needed. This project has gone through 2 or 3 major framwork changes.
Scientific study is a good thing for the government to be involved in, cerainly better than the FAA, HUD, Farm Subsidies etx
I'll agree to disagree with you here, I've been waiting for the results of this experiment for a while now
Huh? It already is. Name one aspect of science that is not (a) funded by the gov't, either directly or indirectly, and (b) isn't ultimately used by the military in some capacity.
Ever since WWII, the key to getting ahead in science is to understand its potential military component.
That's strange... I see the dimple and vortex everytime I flush the toilet... So what's the big deal?
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