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04/30/2010
Big Projects Working Fine
The theme of this month's column is big projects that have either had severe problems or there have been serious questions as to the feasibility of achieving the project goals. Last week marked the 20th anniversary of the launching of one such project - the Hubble Space Telescope. Just a few weeks ago, there was good news about another huge project - the Large Hadron Collider (LHC). In addition to having discussed the LHC and the Hubble in past columns, we've talked about the National Ignition Facility (NIF) and one of its goals -to achieve nuclear fusion. Earlier this year there was also good news leading to optimism on this front. On my own personal level, the definition of a big project is nowhere near as profound, complicated or as costly as these truly monumental projects. Last month I mentioned the severe water problem in our basement when a nor'easter hits us. I noted that an attempt to solve the problem with a sump pump had failed to stem the flooding.
Last week we bit the bullet and (at a cost of some $14K - that's monumental to me!) had our basement subjected to "water management" treatment. The project involved over ten hours of labor by as many as 11 workers simultaneously jackhammering, carrying out chunks of our concrete flooring and dirt, installing two sump pumps and a drainage system and covering it all up with cement . The crew, all Hispanic, worked diligently and left with the admonition that I could not put things back against the walls for at least four days in order to allow the cement to cure. You would not believe the two huge piles of furniture, bookcases, cabinets, golf clubs, books, paintings, etc., etc. that have to be sorted out and pushed back in place. I wanted to cry. Never start such a project until you've thrown out everything possible before the workers arrive! Will our basement be dry, no matter what the deluge? That remains to be seen but I'm optimistic.
OK, let's turn to a truly huge endeavor, one of the most successful scientific projects in the history of mankind - the Hubble Space Telescope. We've all seen the amazing pictures of our universe that Hubble has returned and I won't go into the scientific achievements the Hubble has been a part of. However, you may remember that Hubble, launched on April 24, 1990, as with our sump pump, failed to deliver what was expected. The first images were fuzzy and it was soon determined that the out-of-focus images were due to the fact that the Hubble's primary mirror had not been ground properly and that certain parts of the mirror were too flat. Though the error in grinding was a mere couple of microns (less than the width of a human hair), the result was disastrous and much handwringing and blaming was apportioned between NASA and Perkin Elmer, the company that ground the mirror.
The wonderful pictures that we're accustomed to seeing from Hubble did not start to appear until 1993, when Space Shuttle astronauts installed a new camera and optics designed to compensate for the defective mirror. It was like putting prescription glasses on the telescope. Over the years, there have been other shuttle missions to fix problems and/or maintain the Hubble. Last year our astronauts managed a truly impressive upgrade making the Hubble a hundred times more powerful than it was, according to NASA.
As a battery person, I was intrigued to learn that one of the tasks last year was to replace the two 460-pound nickel-hydrogen battery modules that supply the power to Hubble in the nighttime phases of its orbits. The replaced nickel-hydrogen batteries had lasted 13 years longer than their design orbital life! Makes me proud of the battery community. Credit must be shared with the engineers at Goddard Space Flight Center who carefully monitored and managed the charging currents and temperatures of the batteries on a daily basis, according to NASA. That's a lot of tender loving care over a period of twenty years!
You've almost certainly seen the most famous of the Hubble pictures, "Pillars of Creation", taken in 1995. This picture of a huge gas/dust cloud in which stars are being born was awe-inspiring when it was released. But now you must log on to the nasa.gov Web site and see the latest picture, "Pillars and Jets HH 901/902". After finding the picture, you can blow it up to overfill the screen and get blown away by the detail and colorful image. What impresses me most, aside from its spectacular nature, is that this pillar of gas and dust is three light-years tall; that's roughly 18 trillion miles! It gives one some idea of the immensity of our universe.
Another huge project that deals in trillions is the ten billion dollar/euro Large Hadron Collider near Geneva that, as we discussed back in 2008, suffered a major catastrophe due to a faulty soldering job. It took a long time and I'm sure many millions of dollars, but the LHC just made headlines again; this time the news is great! A few weeks ago, on March 30, the LHC team sent two beams of protons around the collider and the beams collided at energies not achieved in any other particle accelerator, ever.
The protons in each beam achieved energies of 3.5 trillion electron volts (Tev). A collision of two of these 3.5 Tev protons involves a total energy of 7 Tev. The ultimate goal of the LHC is to collide two proton beams of 7 Tev for a total energy of 14 Tev. If you are not comfortable with electron volts, the temperature generated in such a high energy collision, according to an article in the Wall Street Journal by Michio Kaku, has not been seen since the Big Bang itself some 13.7 billion years ago. According to Wikipedia, 1 Tev is equivalent to the kinetic energy of a flying mosquito. This may not sound like a lot of energy but remember that we're talking about single teensy protons, which, at 7 Tev will be moving at 99.9999991 percent of the speed of light! When two protons collide at those speeds, that's a cosmic event!
What is the purpose of LHC? One goal is to find the Higgs boson, a particle that is postulated to be responsible for the fact we have mass, or at least that the fundamental particles of which we are composed have mass. At least that's the way I understand it. Other objectives are to shed light on such things as dark matter, new forces, new dimensions (as in string theory), new particles and possible unification of forces (could quantum mechanics and Einstein finally be united?). To a physicist, a smoothly operating LHC must be a thing of real beauty. It's appropriate that one of the groups involved in the LHC is the Large Hadron Collider beauty experiment (LHCb) group.
I visited the LHCb Web site and found that already they have reconstructed their first Beauty Particle ( called B+) from the maze of particles generated by the collisions of the 3.5 Tev protons. If you're not a nuclear physicist, this beauty particle is composed of an anti-quark b and a quark u. I will not begin to try to describe these various particles but just want to note that often they have extremely short lives as free particles. For example, the anti-quark b has a lifetime of only about a trillionth of a second, while the B+ Beauty Particle only gets to travel a couple of millimeters in the LHC before it decays into two other particles that also don't last long before they decay, etc. etc.
Think of the complexity of trying to keep track of all these decaying particles while there are, who knows?, thousands or millions of other collisions going on at the same time. Last week I visited the Web site of another LHC group called ATLAS, and I gather that they had seen over 60 million proton-proton collisions at that time. The ATLAS group is rather impressive - about 3000 physicists from all over the world, including a thousand students! The ATLAS section of the LHC is about half as big in size as the Notre Dame Cathedral and weighs as much as the Eiffel Tower, to quote some of the statistics on the ATLAS site. If all the data from the LHC were recorded while operating, it would fill a hundred thousand CDs per second! Fortunately, they only record those events promising interesting physics, the equivalent of about 27 CDs per minute. The ATLAS Web site likens running LHC to the creation of the conditions of the Big Bang at a rate of 30 million times a second. The complexity of the computer software to separate out all this huge amount of data must be overwhelming.
With all those physicists and all that data, I expect a torrent of papers to be forthcoming with, hopefully, the answers to some of science's most fundamental questions. The last huge project we'll discuss, Lawrence Livermore National Lab's National Ignition Facility has somewhat more practical missions. The most interesting one to me is the one in which 192 powerful laser beams, converted into X-rays along the line, will be fired simultaneously into a small spherical target filled with deuterium and tritium, two hydrogen isotopes. The hope is that the X-rays will compress the tiny sphere and the hydrogen at temperatures high enough to induce nuclear fusion, generating more energy than the energy put into the process. This, of course, has been the Holy Grail of energy researchers ever since the explosion of the first hydrogen bomb, if not before. NIF is also concerned with the guaranteeing of the readiness of our nuclear arsenal to perform as expected without the need for nuclear testing in the form of exploding nuclear weapons.
In a January 28 press release and an article published on the online Web site of Science, NIF announced that it had taken an important step toward achieving the fusion objective. There had been skepticism about NIF's ability to focus those 192 laser beams/X-rays into such a small space. One concern was an adverse reaction between the laser beams and the hot plasma generated in the targets, with the plasma interaction destroying the symmetry needed to uniformly compress the target contents. It turns out that NIF has in reality been able to actually use the feared interaction to control the symmetry of the tiny volume where the hoped-for fusion will take place. In other words, the goal of achieving a symmetrical compression of the target hydrogen isotopes in the experiment now seems much more feasible.
All in all, three of the world's biggest scientific projects either have been or promise to be running smoothly. We can look forward with more confidence to the answers to some of the most profound questions in science and technology.
As for my basement, I notice that one of the new sump pumps is pumping out water onto our driveway even though it hasn't rained for a few days. I'm taking this as a good sign? And this week two young fellows, again Hispanic, showed up to move back into place the larger items from the central pile of stuff. One of the fellows was reasonably husky but the other was a slight young man who seemed to me barely five feet tall. I was shocked to see how these fellows handled fully loaded full-size file cabinets and bookcases loaded with books. Perhaps just as shocking was the fact that, as they were leaving, I reached in my pocket for my wallet to give them a tip and they refused, saying it was their job! I have no idea as to whether all those workers were legal, illegal or whatever, but they certainly were hardworking and conscientious and I can understand both sides of the Arizona controversy.
Next column, hopefully, will be posted on May 31 or before.
Allen F. Bortrum
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