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Submission + - The Psychology Behind G.W. Bush's Decision-Making

An anonymous reader writes: Psychologists John P. Briggs and John P. Briggs II make a highly detailed, convincing (and interesting) case that George W's decisions as president are driven by a deep sense of inadequacy and a fear of being found out. "The senior Bush had been a star baseball player in high school and college, a highperforming student, a war hero, and a successful oil man. ... The son discovered early that he couldn't conceivably measure up to such accomplishments, and we can only imagine his despair ..."

Submission + - Was Einstein right? Scientists provide first peek

mknewman writes:

14 April 2007
For the past three years a satellite has circled the Earth, collecting data to determine whether two predictions of Albert Einstein's general theory of relativity are correct. Today, at the American Physical Society (APS) meeting in Jacksonville, Fla., Professor Francis Everitt, a Stanford University physicist and principal investigator of the Gravity Probe B (GP-B) Relativity Mission, a collaboration of Stanford, NASA and Lockheed Martin, will provide the first public peek at data that will reveal whether Einstein's theory has been confirmed by the most sophisticated orbiting laboratory ever created.

Podcasts and audio downloads will be available online as soon as we can arrange them.

"Gravity Probe B has been a great scientific adventure for all of us, and we are grateful to NASA for its long history of support," said Everitt. "My colleagues and I will be presenting the first results today and tomorrow. It's fascinating to be able to watch the Einstein warping of spacetime directly in the tilting of these GP-B gyroscopes — more than a million times better than the best inertial navigation gyroscopes."The GP-B satellite was launched in April 2004. It collected over a year's worth of data that the Stanford GP-B science team has been poring over for the past 18 months. The satellite was designed as a pristine, space-borne laboratory, whose sole task was to use four ultra-precise gyroscopes to measure directly two effects predicted by general relativity. One is the geodetic effect-the amount by which the mass of the Earth warps the local space-time in which it resides. The other effect, called frame-dragging, is the amount by which the rotating Earth drags local space-time around with it. According to Einstein's theory, over the course of a year, the geodetic warping of Earth's local space-time causes the spin axes of each gyroscope to shift from its initial alignment by a minuscule angle of 6.606 arc-seconds (0.0018 degrees) in the plane of the spacecraft's orbit. Likewise, the twisting of Earth's local space-time causes the spin axis to shift by an even smaller angle of 0.039 arc-seconds (0.000011 degrees) — about the width of a human hair viewed from a quarter mile away — in the plane of the Earth's equator. GP-B Scientists expect to announce the final results of the experiment in December 2007, following eight months of further data analysis and refinement. Today, Everitt and his team are poised to share what they have found so far-namely that the data from the GP-B gyroscopes clearly confirm Einstein's predicted geodetic effect to a precision of better than 1 percent. However, the frame-dragging effect is 170 times smaller than the geodetic effect, and Stanford scientists are still extracting its signature from the spacecraft data. The GP-B instrument has ample resolution to measure the frame-dragging effect precisely, but the team has discovered small torque and sensor effects that must be accurately modeled and removed from the result.

"We anticipate that it will take about 8 more months of detailed data analysis to realize the full accuracy of the instrument and to reduce the measurement uncertainty from the 0.1 to 0.05 arc-seconds per year that we've achieved to date down to the expected final accuracy of better than 0.005 arc-seconds per year," says William Bencze, GP-B Program Manager. "Understanding the details of this science data is a bit like an archeological dig: a scientist starts with a bulldozer, follows with a shovel, and then he finally uses dental picks and toothbrushes to clear the dust away from the treasure. We are passing out the toothbrushes now."

The two discoveries

Two important discoveries were made while analyzing the gyroscope data from the spacecraft: 1) the "polhode" motion of the gyroscopes damps out over time, and 2) the spin axes of the gyroscopes were affected by small classical torques. Both of these discoveries are symptoms of a single underlying cause: electrostatic patches on the surface of the rotor and housing. Patch effects in metal surfaces are well known in physics, and were carefully studied by the GP-B team during the design of the experiment to limit their effects. Though previously understood to be microscopic surface phenomena that would average to zero, the GP-B rotors show patches of sufficient size to measurably affect the gyroscopes' spins.

The gyroscope's polhode motion is akin to the common "wobble" seen on a poorly thrown (American) football, though it shows up in a much different form for the ultra-spherical GP-B gyroscopes. While it was expected that this wobble would exhibit a constant pattern over the mission, it was found to slowly change due to minute energy dissipation from interactions of the rotor and housing electrostatic patches. The polhode wobble complicates the measurement of the relativity effects by putting a time-varying wobble signal into the data.

The electrostatic patches also cause small torques on the gyroscopes, particularly when the space vehicle axis of symmetry is not aligned with the gyroscope spin axes. Torques cause the spin axis of the gyroscopes to change orientation, and in certain circumstances, this effect can look like the relativity signal GP-B measures. Fortunately, the drifts due to these torques has a precise geometrical relationship to the misalignment of the gyro spin/vehicle symmetry axis and can be removed from the data without directly affecting the relativity measurement.

Both of these discoveries first had to be investigated, be precisely modeled and then be carefully checked against the experimental data before they are removed as sources of error. These additional investigations have added more than a year to the data analysis, and this work is still in process. To date, the team has made very good progress in this regard, according to its independent Science Advisory Committee, chaired by relativistic physicist Clifford Will of Washington University in St. Louis, Mo., that has been monitoring every aspect of GP-B for the past decade.

In addition to providing a first peek at the experimental results at the APS meeting, the GP-B team has released an archive of the raw experimental data. The data will be available through the National Space Sciences Data Center at the NASA Goddard Space Flight Center beginning in June 2007.

Conceived by Stanford Professors Leonard Schiff, William Fairbank and Robert Cannon in 1959 and funded by NASA in 1964, GP-B is the longest running, continuous physics research program at both Stanford and NASA. While the experiment is simple in concept — it utilizes a star, a telescope and a spinning sphere — it took more than four decades and $760 million to design and produce all the cutting-edge technologies necessary to bring the GP-B satellite to the launch pad, carry out this "simple" experiment and analyze the data. On April 20, 2004, GP-B made history with a perfect launch from Vandenberg Air Force Base in California. After a four-month initialization and on-orbit check-out period, during which the four gyroscopes were spun up to an average of 4,000 rpm and the spacecraft and gyro spin axes were aligned with the guide star, IM Pegasi, the experiment commenced. For 50 weeks, from August 2004 to August 2005, the spacecraft transmitted more than a terabyte of experimental data to the GP-B Mission Operations Center at Stanford. One of the most sophisticated satellites ever launched, the GP-B spacecraft performed magnificently throughout this period, as did the GP-B Mission Operations team, comprised of scientists and engineers from Stanford, NASA and Lockheed Martin, said Stanford Professor Emeritus Bradford Parkinson, a co-principal investigator with John Turneaure and Daniel DeBra, also emeritus professors at Stanford. The data collection ended on Sept. 29, 2005, when the helium in spacecraft's dewar was finally exhausted. At that time, the GP-B team transitioned from mission operations to data analysis.

Over its 47-year lifetime, GP-B has advanced the frontiers of knowledge, provided a training ground for 79 doctoral students at Stanford (and 13 at other universities), 15 masters degrees, hundreds of undergraduates and dozens of high school students who worked on the project. In addition, GP-B spawned over a dozen new technologies, including the record-setting gyroscopes and gyro suspension system, the SQUID (for Superconducting QUantum Interference Device) gyro readout system, the ultra-precise star-pointing telescope, the cryogenic dewar and porous plug, the micro-thrusters and drag-free technology and the Global Positioning System-based orbit determination system. All of these technologies were essential for carrying out the experiment, but none existed in 1959 when the experiment was conceived. Furthermore, some technologies which were designed at Stanford for use in GP-B, such as the porous plug that controlled the escape of helium gas from the dewar, enabled and were used in other NASA experiments such as COBE (the COsmic Background Explorer, which won this year's Nobel prize) WMAP (for Wilkinson Microwave Anisotropy Probe) and the Spitzer Space Telescope.

The experiment's final result is expected on completion of the data analysis in December of this year. Asked for his final comment, Francis Everitt said: "Always be suspicious of the news you want to hear."

NASA's Marshall Space Flight Center manages the GP-B program and contributed significantly to its technical development. NASA's prime contractor for the mission, Stanford University, conceived the experiment and is responsible for the design and integration of the science instrument, as well as for mission operations and data analysis. Lockheed Martin, Stanford's major subcontractor, designed, integrated and tested the spacecraft and built some of its major payload components, including the dewar and probe that houses the science instrument. NASA's Kennedy Space Center, Fla., and Boeing Expendable Launch Systems, Huntington Beach, Calif., was responsible for the launch of the Delta II.

Bob Kahn, author of this press release, is the public affairs coordinator for Gravity Probe B at Stanford.

Submission + - Cell Phones May Be Destroying the Bee Populations

GenKreton writes: Bee populations went from steadily declining in some countries last year to dramatic mass-deaths this year. The west coast US has lost up to 60%, and the east coast has lost up to 70%; Germany, France, Britain and other countries are also sustaining massive bee population losses. So what's causing it? Some scientists say it's the cell phones.
United States

Submission + - Gary Kasparov is the Russian Martin Luther King?

reporter writes: "Like Martin Luther King of an older generation, gutsy Gary Kasparov has again defied authorities and lead a peace demonstration demanding basic civil rights and fair elections. Quoting Vladimir Ryzhkov, Bloomberg reports that the Russian police broke up the demonstration by "beating grandmothers and pensioners with billy clubs, hitting them in the back". Kasparov, a former chess champion, runs the risk of being permanently checkmated by President Vladimir Putin. Will Kasparov share the same untimely end that concluded King's life?"
Data Storage

Open Source Highly Available Storage Solutions? 46

Gunfighter asks: "I run a small data center for one of my customers, but they're constantly filling up different hard drives on different servers and then shuffling the data back and forth. At their current level of business, they can't afford to invest in a Storage Area Network of any sort, so they want to spread the load of their data storage needs across their existing servers, like Google does. The only software packages I've found that do this seamlessly are Lustre and NFS. The problem with Lustre is that it has a single metadata server unless you configure fail-over, and NFS isn't redundant at all and can be a nightmare to manage. The only thing I've found that even comes close is Starfish. While it looks promising, I'm wondering if anyone else has found a reliable solution that is as easy to set up and manage? Eventually, they would like to be able to scale from their current storage usage levels (~2TB) to several hundred terabytes once the operation goes into full production."

Submission + - Li-Ion Batteries Coming To A Car Near You?

mrneutron2004 writes: Current generation electric and hybrid vehicles use NiMH (Nickel Metal Hydride) batteries, owing to their greater durability and safety relative to Li-Ion (Lithium Ion) batteries, which are commonly found in consumer class mobile devices (that hopefully don't burst into flames). eries-coming-to-a-car-near-you.html?Itemid=60

Submission + - New Laws of Robotics proposed for US kill-bots

jakosc writes: The Register has a short commentry about a proposed new set of laws of robotics for war robots by John S Canning of the Naval Surface Warfare Centre. Unlike Azimov's three laws of robotics Canning proposes (pdf) that we should "Let machines target other machines and let men target men." although this sounds OK in principle, "a robot could decide under Mr Canning's rules, to target a weapon system such as an AK47 for destruction on its own initiative, requiring no permission from a human. If the person holding it was thereby killed, that would be collateral damage and the killer droid would be in the clear.."
It's funny.  Laugh.

Submission + - Who/what should a hero fight?

An anonymous reader writes: Due to a weird radioactive accident in my lab a few months ago, I have acquired some superpowers that people usually only dream of. I always thought that what I saw in comics were just fiction, but now I know better. Being a nerd and a nice guy, I followed the lesson from the heroes in comics, and started to fight crime in my region. Everything is going nicely, but the more I fight crime, more it seems that the world is getting worse and worse. Poor people are poorer, people keep dying of hunger and people keep on killing each other. So, I decided to ask Slashdot: since I have power enough to change the world and fight injustices, what should I do to make this world better? Also, heroes cannot work alone, since the world is so big and there is a lot to fight, so who should I unite with? I think you can understand why I'm not signing this summary.

Submission + - Major Record Labels Withdraw from RIAA

s3pHiRoTh writes: "Music industry executives announced this morning that they were withdrawing support for the trade group the Recording Industry Association of America (RIAA) and launching a new representative body called Respect the Artist, Respect the Audience (RARA)."

Submission + - Google Introduces TiSP (beta)

ceresur writes: Google has launched a free consumer broadband wifi internet service. From the PR:

"Google Inc. today announced the launch of Google TiSP (BETA)(TM), a free in-home wireless broadband service that delivers online connectivity via users' plumbing systems. The Toilet Internet Service Provider (TiSP) project is a self-installed, ad-supported online service that will be offered entirely free to any consumer with a WiFi-capable PC and a toilet connected to a local municipal sewage system."

There is a page describing how to install TiSP and an FAQ.

Submission + - Holy cow! Alien abductions on the rise

An anonymous reader writes: It's a growing problem. Countless bovines have disappeared from dairy farms everywhere. And the numbers of missing cows are on the rise. See for yourself (Flash required).

Submission + - What should I ask Slashdot?

TodMinuit writes: "Dearest Slashdot: Recently, I've wanted to ask Slashdot something. Unable to come up with a question myself, I thought who better to ask what I should ask Slashdot than Slashdot itself? Surely the very people answering the question are quite capable of coming up with one. So, Slashdot, what should I ask Slashdot?"

Submission + - Grow-your-own Viagra craze hits garden centers...

colfer writes: From today's Independent

The plant is winter-flowering heather, and botanists at the Royal Botanic Gardens, Edinburgh, many of them heather experts who have recognised the source of its active ingredient, now expect it to be the next must-have plant in British gardens. Demand is already high. Nurseries and garden centres in some areas are having trouble finding sufficient supplies as word spreads of the plant's unexpected properties.
But not everyone is happy about this new discovery. One woman shopping at a Wyvales in Dorking yesterday said: "It's amazing. My husband has never shown any interest in gardening before, but now he's out there night and day fussing over his heathers. Frankly, I preferred it when he left the garden to me and wasn't so frisky."
United States

Submission + - Continental Captain Saves Plane From Coughing Girl

MuValas writes: "Thanks to quick thinking, a Captain of a Continental flight saved his passengers by kicking a 16-year old girl off the plane. Her offense? Having a coughing fit. I believe the captain suspected the coughing to be some sort of lung-based nuke-uler weapon, or perhaps he just got dumped too many times by 16-year old girls and saw an opportunity for revenge."

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