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NASA Gravity Probe Set for Launch
The Real Dr John writes "NASA announced
yesterday that its longest running program, Gravity Probe B, was ready and
scheduled for launch on April 17th. The project has taken 44 years to complete,
at a cost of approximately $700 million. The reason for the high cost is that
the probe contains the most sensitive gyroscopic equipment ever created, which
will be used to test Einstein's theory of gravity. Einstein predicted that the
gravity created by a large body warped space-time, but he also predicted that if
the large body was rotating it would create a drag effect on space-time
known as frame dragging. Gravity Probe B will be able to test
Einstein's theory using Earth's relatively small gravitational field because the
instruments are so sensitive."
Seems God plays roulette even if he doesn't play dice.
The slightest bit of interference could deem it unusable data with as much precision the gyroscopes will be operating. I have a feeling that even interference they are not thinking about (who am I kidding, this is nasa) such as solar radiation, and the magnetic north shift (which as of late, has been about 10 miles a year) will alter the results of this test dramaticly.
-- johntracy.com, because everybody else is wrong.
large body was rotating it would create a drag effect on space-time known as frame dragging.
I think we're all familiar with time dialation (if you haven't read "The Elegent Universe", you're missing the best explanation of *why* time dislation occurs that I have ever heard), but what is frame dragging? What kind of effects does it have on the observer?
Javascript + Nintendo DSi = DSiCade
More interestingly enough, what can we use this for? No, this isn't sarcasm, but how can we apply these scientific principals to help our daily lives and to understand the universe better?
Comments anyone?
So what happend to Gravity Probe A?
(sorry had to ask)
i viewed the elegant universe, the other day by brian green, and am currently reading the text, much has changed in theory over the last 44 years, string theory for one, currently holds the possiblility that gravtiy strings are looped and therefore capable of jumping from our current brane/dimension. will this allow and or test for this theory or is the device antiquated before deployment? I guess thats a risk involved with such a long dev cycle. hopefully it will take this into account, or has the CERN project already made this redundant?
Did I mention that my car is a Maybach 62, which costs $380,000? With an expensive car like that, you want to make sure the upholstery doesn't get dirty.
Einstein predicted that the gravity created by a large body warped space-time, but he also predicted that if the large body was rotating it would create a drag effect on space-time known as frame dragging.
AAagh! Mental images of my ex dancing! *SHUDDER!*
NASA announced yesterday that its longest running program, Wooden Block B, was ready and scheduled for dropping off the Empire State Building on April 17th. The project has taken 44 years to complete, at a cost of approximately $700 million. The reason for the high cost is that the probe contains the most expensive wood ever created, which will be used to test Newton's theory of gravity. Newton predicted that an attractive force known as 'gravity' will act between any two bodies. Wooden Block B will be able to test Newton's theory using Earth's gravitational field, and a very tall building.
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That project has been kicking around Stanford for decades. I saw that satellite under construction almost twenty years ago. It's basically a subsidy program for PhD students, not a satellite program. If that job had been outsourced to Hughes or Loral, it would have launched decades ago.
If you look on the web site, you'll see they have already contributed to the technology sector. http://einstein.stanford.edu/content/spinoffs/tech nology.html
I found the following quote especially interesting:
Francis Everitt, the principal investigator of the project, said: "Aren't Einstein's theories all established and confirmed? After all it was 50 years ago that Einstein himself died and it's 100 years next year when he developed his first theory of relativity. Don't we already know it all? The answer is no."
I wonder what other theories that are generally accepted throughout the scientific community have not been completely tested and/or verified. And, quite frankly, I'm surprised that there isn't much more VC and grant money available to go and do research on stuff like this. Afterall, these projects are quite prestigious.
In addition to the sensitivity problem, I wonder if this could be an experiment whose time has passed.
In 1995, the GP-B was described as the "only experiment ever devised to test [the existence of frame-dragging]."
However, in 1997 NASA announced that it had successfully tested frame dragging. See also here.
Only Women Bleed (Sex, Sharia remix)
See article
Professional Wild-Eyed Visionary
They should launch anti-gravity probes. Wouldn't even need rockets and save us taxpayers some bucks.
Table-ized A.I.
Someone setup an experiment about 10 years ago with 2 highly percise clocks one was set up on the top of a tall build and the other was set at the bottom...they ticked and stoped at the same exact and the clock on top of the building was very slightly behind the clock on the bottom...so I guess that should say something about his theory of relativaty.
This comment is offtopic and stolen from here. Bloody trolls!
//Blessed are they that run around in circles, for they shall be known as wheels.
The impact on science is quite straightforward. as this is science. Science is about testing theories. Without that, science is just a religion.
GR predicted that Newtonian mechanics are too simplistic. This is one of the tests that verifies this. Anyway, any applications of this test are another 50 or 500 years away. Just like the applications of discovery of electrons (typing away on my electron machine).
Many theories of gravity, even those disagreeing wildly with GR, have frame dragging. If there are no decent alternative hypotheses that make different predictions, is it really worth spending hundreds of millions of dollars on conducting this experiment?
From the article :
Since the project was conceived by three scientists after a naked midday swim at Stanford University's pool, more than 1,000 people have worked on the satellite. Two of its founders are dead. More than 90 people have earned their doctorates working on the project.
Naked physicists... wow... with the current administration in charge, this project would have never been approved.
Very cool experiment (well worth the cash) however I think the LATOR relativity experiment would be much more interesting and scientifically useful.
And probably not much more expensive.
LATOR is capable of testing string theory, an exciting but so far merely theoretical development in high energy physics. LATOR also seems to be much more accurate, and less likely to receive interference.
I do hope that this experiment works out, however as other posters have mentioned, there only has to be one unexpected source of error to totally screw this up.
Cheers,
Justin Wick
This guys post is taken from another discussion and another Slashdot user. Verbatim.
He's a troll relegated to 0 karma land, and desperate for anyway out.
See UID's comment on his post: here
Don't let this guy walk off with 5 mod points for such a stupid trick.
-Malakai
A Dragon Lives in my Garage
Finally we're the ones doing the probing!
What is the difference if NASA sells the rights to companies to produce products WE, the taxpayer, funded the research for? I would rather keep the taxes I paid because the cost of these products is not reduced anyway. These companies get free R/D and then charge us top dollar anyway...Let them fund the R/D and let the demand for these products determine what gets made and for how much. If it is the products that justify the taxpayer expense, shouldn't WE, the taxpayer, have the rights to profits from the products? How did NASA become a technology pimp?
... the project that ate Stanford.
:)
When I was a grad student there, we had a running joke that nobody could get an astrophysics degree without selling at least a piece of their soul to Francis Everett, the chief booster for this project.
I was there when a rogue group suggested that, in the intervening four decades, technology had advanced enough to do the frame-dragging experiment with a laser-coordinated satellite net for half the cost.
We also circulated the "fact" that the GP-B launch date slipped by about 1.05 days per day. A friend defined it as a new universal constant for project overruns...
The Mongrel Dogs Who Teach
Hmmm. When World War II broke out, the US had discovered that, while its tactics with torpedos were more or less sound, they came to naught -- because the actual torpedos had this nasty habit of breaking apart on impact, rather than (say) exploding. It took two years (and who knows how many lives) to get that problem fixed.
The general rule seems, to my reading of history, to be that the military tends to be effective but not necessarily cost-efficient. Or put another way: Throw enough money at any technological problem and it will be solved. People tend to be freer with the gobs of money if they think it's related to national security.
The Mongrel Dogs Who Teach
Duke Nukem Forever was originally first described in a Bell Labs whitepaper personally written by Ken Thompson and Dennis Ritchie in early 1970, just over 34 years ago. The whitepaper said that Duke Nukem Forever would run on Bell Labs' new UNIX system, and would be available "sometime before the end of the year". Bell started taking orders the next week, and the historic first order for DNF, by the U.S. patent office, was placed on that day. Eight months later, despite not yet being finished, Duke Nukem Forever was proclaimed "Game of the Year" by the October issue of the Association for Computing Machinery quarterly journal.
Since then the game has changed publishers and target platform numerous times, and changed intended game engines a stunning 57 times. Of the original five-man development team, two are still on the project, one currently holds a senior managerial position at Intel, and two are since dead. In 1995 when the original UNIX intellectual property block was licensed from Novell to SCO, the Duke Nukem Forever project was split off and separately sold to a company called 3D Realms, who still oversees it and currently publically states that DNF will be available "when it's done".
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
Can I buy one of these satellites on ThinkGeek?
"Simple words such as 'better' or 'faster' are best used by simpletons. Life [...] is more complicated." - TMC
Hubble has had a pretty good look at the spectra of supermassive black holes at the ceters of local galaxies. With a nice close look at those centers, there is turbulences, physical discontinuities in the acretion disks around the supermassive black holes, and the only good candidate for the phenomena is frame dragging...
I mean it'll be cool to see if the numbers and the phenomena match, but it's not like there's going to be wild surprise.
Genda
Only cosmology and black hole physics can really test GR.
Humm, methinks you may well have the black hole physics part of it backwards. One thing we get damned little out of a black hole is information about its characteristics. We can get a general, plus or minus 20% guess on its mass by measuring the orbital velocities and distances to all the other stars in the locality.
The only other tidbit of info we can eek out of the observations is the miss-match between expected velocities of the really nearby stars, and the predicted velocity at that distance based on the above SWAG on its mass from averageing the orbits of the more distant stars.
From that we can deduce the direction and speed of the hole rotation as directly evidenced by the orbital errors of these nearby stars caused by what may well be frame dragging from the rotation of the black hole.
However, the closest such black hole isn't easily observable (IIRC it's Saggitarious B) due to all the dirt and dust from previous supernova's surrounding the center of our own galaxy, the thing you know as the Milky Way. Our far infrared capabilities that can see better thru all that junk will come online with the James Webb telescope and hopefully give us a better view.
In the meantime we have to look to other, much more distant galaxies, where the sheer distances preclude making truely accurate measurements on any one object. I think we do more by doppler effects causeing line spreading, and statistical analysis of that spreading, than by any direct observations of any individual stars in those distant galaxies. Statistics tend to be fuzzy as we all know.
This device, by giving us a very good signal to noise ratio calibration point, will let us analyse those distant objects with considerably more precision than we currently can do. It has the potential of tightening up our "guesses" by at least 2 orders of magnitude, maybe more. Thats worthwhile science, and will narrow the field of candidates for the TOE considerably.
Cheers, Gene
Yep. At the start of World War II for the US, in December 1941, it was amongst the weakest military-wise in the world. By August, 1945, less than four years later, it had nuked Japan. Nuked. In 1945. Look at the cars in 1945. Some military dude said "Let's make a bomb" and they built it.
But it cost a few billion bucks. GDP-wise, it was probably the largest project in US history. But such a pretty cloud!
A NYC lawyer blogs. http://www.chuangblog.com/
From the ESA website
LISA
LISA is an ESA-NASA mission involving three spacecraft flying approximately 5 million kilometres apart in an equilateral triangle formation. Together, they act as a Michelson interferometer to measure the distortion of space caused by passing gravitational waves. Lasers in each spacecraft will be used to measure minute changes in the separation distances of free-floating masses within each spacecraft.
The LISA mission is designed to search for and detect gravitational radiation from astronomical sources. In the process, LISA can test some of the fundamental tenets of the theory of gravitation.
The most predictable sources
The most predictable sources of gravitational waves are binary star systems in our galaxy. LISA's observations of these systems would be of interest both for fundamental physics and for astrophysics. The LISA design is such that both the amplitude and also the polarization of gravitational waves can be measured. If gravitational radiation from known binary systems is not detected, or is detected with amplitudes or polarizations not predicted by general relativity, then general relativity must be wrong. If the sources are detected then the polarization measurement reveals the angle of inclination of the orbit of the binary system. This is a crucial missing factor from many optical observations of these systems, and is necessary in order to infer the mass of the stars in the binary pair.
Why so much emphasis on Einstein's Theory all of a sudden??
SBD