Astronomers measure distance to star celebrated in ancient literature and legend

PASADENA—The cluster of stars known as the Pleiades is one of the most recognizable objects in the night sky, and for millennia has been celebrated in literature and legend. Now, a group of astronomers has obtained a highly accurate distance to one of the stars of the Pleiades known since antiquity as Atlas. The new results will be useful in the longstanding effort to improve the cosmic distance scale, as well as to research the stellar life-cycle. In the January 22 issue of the journal Nature, astronomers from the California Institute of Technology and the Jet Propulsion Laboratory report the best-ever distance to the double-star Atlas. The star, along with "wife" Pleione and their daughters, the "seven sisters," are the principal stars of the Pleiades that are visual to the unaided eye, although there are actually thousands of stars in the cluster. Atlas, according to the team's decade of careful interferometric measurements, is somewhere between 434 and 446 light-years from Earth.\

The range of distance to the Pleiades cluster may seem somewhat imprecise, but in fact is accurate by astronomical standards. The traditional method of measuring distance is by noting the precise position of a star and then measuring its slight change in position when Earth itself has moved to the other side of the sun. This approach can also be used to find distance on Earth. If you carefully record the position of a tree an unknown distance away, move a specific distance to your side, and measure how far the tree has apparently "moved," it's possible to calculate the actual distance to the tree by using trigonometry.

However, this procedure gives only a rough estimate to the distance of even the nearest stars, due to the gigantic distances involved and the subtle changes in stellar position that must be measured. Further, the team's new measurement settles a controversy that arose when the European satellite Hipparcos provided a distance measurement to the Pleiades so much nearer the distance than assumed that the findings contradicted theoretical models of the life cycles of stars.

This contradiction was due to the physical laws of luminosity and its relationship to distance. A 100-watt light bulb one mile away looks exactly as bright as a 25-watt light bulb half a mile away. So to figure out the wattage of a distant light bulb, we have to know how far away it is. Similarly, to figure out the "wattage" (luminosity) of observed stars, we have to measure how far away they are. Theoretical models of the internal structure and nuclear reactions of stars of known mass also predict their luminosities. So the theory and measurements can be compared.

However, the Hipparcos data provided a distance lower than that assumed from the theoretical models, thereby suggesting either that the Hipparcos distance measurements themselves were off, or else that there was something wrong with the models of the life cycles of stars. The new results show that the Hipparcos data was in error, and that the models of stellar evolution are indeed sound. The new results come from careful observation of the orbit of Atlas and its companion--a binary relationship that wasn't conclusively demonstrated until 1974 and certainly was unknown to ancient watchers of the sky. Using data from the Mt. Wilson stellar interferometer (located next to the historic Mt. Wilson Observatory in the San Gabriel range) and the Palomar Testbed Interferometer at Caltech's Palomar Observatory in San Diego County, the team determined a precise orbit of the binary. Interferometry is an advanced technique that allows, among other things, for the "splitting" of two bodies that are so far away that they normally appear as a single blur, even in the biggest telescopes. Knowing the orbital period and combining it with orbital mechanics allowed the team to infer the distance between the two bodies, and with this information, to calculate the distance of the binary to Earth. "For many months I had a hard time believing our distance estimate was 10 percent larger than that published by the Hipparcos team," said the lead author, Xiao Pei Pan of JPL. "Finally, after intensive rechecking, I became confident of our result."

Coauthor Shrinivas Kulkarni, MacArthur Professor of Astronomy and Planetary Science at Caltech, said, "Our distance estimate shows that all is well in the heavens. Stellar models used by astronomers are vindicated by our value." "Interferometry is a young technique in astronomy and our result paves the way for wonderful returns from the Keck Interferometer and the anticipated Space Interferometry Mission that is expected to be launched in 2009," said coauthor Michael Shao of JPL. Shao is also the principal scientist for the Keck Interferometer and the Space Interferometry Mission. The Palomar Testbed Interferometer was designed and built by a team of researchers from JPL led by Shao and JPL engineer Mark Colavita. Funded by NASA, the interferometer is located at the Palomar Observatory near the historic 200-inch Hale Telescope. The device served as an engineering testbed for the interferometer that now links the 10-meter Keck Telescopes atop Mauna Kea in Hawaii.

 

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Robert Tindol
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The coming global peak in oil productionis a grave concern, according to new book

PASADENA, Calif.—Ancient Persians tipped their fire arrows with it, and Native Americans doctored their ails with it. Any way you look at petroleum, the stuff has been around for a long time. Problem is, it's not going to be around much longer--or at least not in the quantities necessary to keep our Hummers humming.

To address the choices society will soon face in the inevitable peaking of worldwide oil production, California Institute of Technology physics professor David Goodstein has written a new book titled Out of Gas: The End of the Age of Oil. Goodstein argues that global production will peak sooner than most people think, possibly in this decade--a view held by a number of geologists--and that the peak itself will be the beginning of serious and widespread social and economic consequences.

"Some say that the world has enough oil to last for another forty years or more, but that view is almost surely mistaken," writes Goodstein, whose past forays into the world of science communication have included his award-winning PBS series The Mechanical Universe, as well as the best-selling book Feynman's Lost Lecture.

Goodstein writes that the worldwide peak will almost surely be highly disruptive, if not catastrophic, considering the difficult American experience of the early 1970s, when U.S. production met its own peak. Since then, U.S. production has been on a downslope that will continue until the tap runs dry.

But even the 1970s' experience would be nothing compared to a worldwide peak, Goodstein explains. Indeed, the country then experienced serious gas shortages and price increases, exacerbated in no small part by the Arab oil embargo. But frustration and exasperation aside, there was oil to buy on the global market if one could locate a willing seller. By contrast, the global peak will mean that prices will thereafter rise steadily and the resource will become increasingly hard to obtain.

Goodstein says that best and worst-case scenarios are fairly easy to envision. At worst, after the so-called Hubbert's peak (named after M. King Hubbert, the Texas geophysicist who was nearly laughed out of the industry in the 1950s for even suggesting that a U.S. production peak was possible), all efforts to deal with the problem on an emergency basis will fail. The result will be inflation and depression that will probably result indirectly in a decrease in the global population. Even the lucky survivors will find the climate a bit much to take, because billions of people will undoubtedly rely on coal for warmth, cooking, and basic industry, thereby spewing a far greater quantity of greenhouse gases into the air than that which is currently released.

"The change in the greenhouse effect that results eventually tips Earth's climate into a new state hostile to life. End of story. In this instance, worst case really means worst case."

The best-case scenario, Goodstein believes, is that the first warning that Hubbert's peak has occurred will result in a quick and stone-sober global wake-up call. Given sufficient political will, the transportation system will be transformed to rely at least temporarily on an alternative fuel such as methane. Then, more long-term solutions to the crisis will be put in place--presumably nuclear energy and solar energy for stationary power needs, and hydrogen or advanced batteries for transportation.

The preceding is the case that Goodstein makes in the first section of the book. The next section is devoted to a nontechnical explanation of the facts of energy production. Goodstein, who has taught thermodynamics to a generation of Caltech students, is particularly accomplished in conveying the basic scientific information in an easily understandable way. In fact, he often does so with wit, explaining in a brief footnote on the naming of subatomic particles, for example, that the familiar "-on" ending of particles, such as "electrons," "mesons," and "photons," may also suggest an individual quantum of humanity known as the "person."

The remainder of the book is devoted to suggested technological fixes. None of the replacement technologies are as simple and cheap as our current luxury of going to the corner gas station and filling up the tank for the equivalent of a half-hour's wages, but Goodstein warns that the situation is grave, and that things will change very soon.

"The crisis will occur, and it will be painful," he writes in conclusion. "Civilization as we know it will come to an end sometime in this century unless we can find a way to live without fossil fuels."

Goodstein dedicates the book "to our children and grandchildren, who will not inherit the riches that we inherited."

The book, published by W.W. Norton & Company, is now available.

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Robert Tindol
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Moore Foundation Awards Additional $17.5 Million for Thirty-Meter Telescope Plans

PASADENA—The Gordon and Betty Moore Foundation awarded $17.5 million to the University of California for collaboration with the California Institute of Technology on a project intended to build the world's most powerful telescope. Coupled with an award by the foundation to Caltech for the same amount, a total of $35 million is now available for the two institutions to collaborate on this visionary project to build the Thirty Meter Telescope (TMT). Their next step will be to work together to formulate detailed design plans for the telescope.

A 30-meter-diameter optical and infrared telescope, complete with adaptive optics, would result in images more than 12 times sharper than those of the Hubble Space Telescope. The TMT will have nine times the light-gathering ability of one of the 10-meter Keck Telescopes, which are currently the largest in the world. With such a telescope, astrophysicists will be able to study the earliest galaxies and the details of their formation as well as pinpoint the processes that lead to young planetary systems around nearby stars.

"We are very pleased that the Gordon and Betty Moore Foundation has recognized the strengths of the University of California and Caltech to carry out such an important project," said UC President Robert C. Dynes. "The giant telescope will help our astronomy faculty stay at the very forefront of that dynamic field of science."

"The University of California and Caltech will work in close and constant collaboration to achieve the goals of the design effort," said Joseph Miller, director of UC Observatories/Lick Observatory, headquartered at UC Santa Cruz. "We've also entered into collaborations with the Association of Universities for Research in Astronomy and the Association of Canadian Universities for Research in Astronomy, both of whom are in the process of seeking major funding."

According to Richard Ellis, director of Caltech Optical Observatories and Steele Professor of Astronomy at Caltech, the Gordon and Betty Moore Foundation's award will provide the crucial funding needed to address the major areas of risk in this large project.

"This next phase is of central importance, because in the course of carrying it out, we will establish the fundamental technologies and methods necessary for the building of the telescope," Ellis said.

Miller and Ellis agree that the TMT is a natural project for UC and Caltech to undertake jointly, given their decades of experience as collaborators in constructing, operating, and conducting science with the world's largest telescopes at the Keck Observatory. The TMT design is a natural evolution of the Keck Telescope design, and many of the same UC and Caltech scientists involved in the creation of the Keck Observatory are deeply involved in the TMT project.

Following the Gordon and Betty Moore Foundation-funded design study, the final phase of the project, not yet funded, will be construction of the observatory at an as-yet-undetermined site. The end of this phase would mark the beginning of regular astronomical observations, perhaps by 2012.

The Gordon and Betty Moore Foundation was established in November 2000, by Intel co-founder Gordon Moore and his wife Betty. The foundation funds outcome-based projects that will measurably improve the quality of life by creating positive outcomes for future generations. Grantmaking is concentrated in initiatives that support the foundation's principal areas of concern: environmental conservation, science, higher education, and the San Francisco Bay area. ### MEDIA CONTACTS: Jill Perry, Media Relations Director, Caltech (626) 395-3226, jperry@caltech.edu

Tim Stephens, Science Writer, University Relations/Public Information Office, University of California, Santa Cruz (831) 459-4352, stephens@ucsc.edu

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Caltech, SLAC, and LANL Set New Network Performance Marks

PHOENIX, Ariz.--Teams of physicists, computer scientists, and network engineers from Caltech, SLAC, LANL, CERN, Manchester, and Amsterdam joined forces at the Supercomputing 2003 (SC2003) Bandwidth Challenge and captured the Sustained Bandwidth Award for their demonstration of "Distributed particle physics analysis using ultra-high speed TCP on the Grid," with a record bandwidth mark of 23.2 gigabits per second (or 23.2 billion bits per second).

The demonstration served to preview future Grid systems on a global scale, where communities of hundreds to thousands of scientists around the world would be able to access, process, and analyze terabyte-sized data samples, drawn from data stores thousands of times larger. A new generation of Grid systems is being developed in the United States and Europe to meet these challenges, and to support the next generation of high-energy physics experiments that are now under construction at the CERN laboratory in Geneva.

The currently operating high-energy physics experiments at SLAC (Palo Alto, California), Fermilab (Batavia, Illinois), and BNL (Upton, New York) are facing qualitatively similar challenges.

During the Bandwidth Challenge, the teams used all three of the 10 gigabit/sec wide-area network links provided by Level 3 Communications and Nortel, connecting the SC2003 site to Los Angeles, and from there to the Abilene backbone of Internet2, the TeraGrid, and to Palo Alto using a link provided by CENIC and National LambdaRail. The bandwidth mark achieved was more than 500,000 times faster than an Internet user with a typical modem connection (43 kilobits per second). The amount of TCP data transferred during the 48-minute-long demonstration was over 6.6 terabytes (or 6.6 trillion bytes). Typical single-stream host-to-host TCP data rates achieved were 3.5 to 5 gigabits per second, approaching the single-stream bandwidth records set last month by Caltech and CERN.

The data, generated from servers at the Caltech Center for Advanced Computing Research (CACR), SLAC, and LANL booths on the SC2003 showroom floor at Phoenix, a cluster at the StarLight facility in Chicago as well as the TeraGrid node at Caltech, was sent to sites in four countries (USA, Switzerland, Netherlands, and Japan) on three continents. Participating sites in the winning effort were the Caltech/DataTAG and Amsterdam/SURFnet PoPs at Chicago (hosted by StarLight), the Caltech PoP at Los Angeles (hosted by CENIC), the SLAC PoP at Palo Alto, the CERN and the DataTAG backbone in Geneva, the University of Amsterdam and SURFnet in Amsterdam, the AMPATH PoP at Florida International University in Miami, and the KEK Laboratory in Tokyo. Support was provided by DOE, NSF, PPARC, Cisco Systems, Level 3, Nortel, Hewlett-Packard, Intel, and Foundry Networks.

The team showed the ability to use efficiently both dedicated and shared IP backbones. Peak traffic on the Los Angeles-Phoenix circuit, dedicated to this experiment, reached almost 10 gigabits per second utilizing more than 99 percent of the capacity. On the shared Abilene and TeraGrid circuits the experiment was able to share fairly over 85 percent of the available bandwidth. Snapshots of the maximum link utilizations during the demonstration showed 8.7 gigabits per second on the Abilene link and 9.6 gigabits per second on the TeraGrid link.

This performance would never have been achieved without the use of new TCP implementations because the widely deployed TCP RENO protocol performs poorly at gigabit-per-second speed. The primary TCP algorithm used was new FAST TCP stack developed at the Caltech Netlab. Additional streams were generated using HS-TCP, implemented at Manchester, and scalable TCP.

Harvey Newman, professor of physics at Caltech, said: "This was a milestone in our development of wide-area networks and of global data-intensive systems for science. Within the past year we have learned how to use shared networks up to the 10 gigabit-per-second range effectively. In the next round we will combine these developments with the dynamic building of optical paths across countries and oceans. This paves the way for more flexible, efficient sharing of data by scientists in many countries, and could be a key factor enabling the next round of physics discoveries at the high-energy frontier. There are also profound implications for integrating information sharing and on-demand audiovisual collaboration in our daily lives, with a scale and quality previously unimaginable."

Les Cottrell, assistant director of SLAC's computer services, said: "This demonstrates that commonly available standard commercial hardware and software, from vendors like Cisco, can effectively and fairly use and fill up today's high-speed Internet backbones, and sustain TCP flows of many gigabits per second on both dedicated and shared intracountry and transcontinental networks. As 10 gigabit-per-second Ethernet equipment follows the price reduction curve experienced by earlier lower-speed standards, this will enable the next generation of high-speed networking and will catalyze new data-intensive applications in fields such as high-energy physics, astronomy, global weather, bioinformatics, seismology, medicine, disaster recovery, and media distribution."

Wu-chun (Wu) Feng, team leader of research and development in Advanced Network Technology in the Advanced Computing Laboratory at LANL, noted: "The SC2003 Bandwidth Challenge provided an ideal venue to demonstrate how a multi-institutional and multi-vendor team can quickly come together to achieve a feat that would otherwise be unimaginable today. Through the collaborative efforts of Caltech, SLAC, LANL, CERN, Manchester, and Amsterdam, we have once again pushed the envelope of high-performance networking. Moore's law move over!"

"Cisco was very pleased to help support the SC2003 show infrastructure, SCINET," said Bob Aiken, director of engineering for academic research and technology initiatives at Cisco. "In addition, we also had the opportunity to work directly with the high-energy physics (HEP) research community at SLAC and Caltech in the United States, SURFnet in the Netherlands, CERN in Geneva, and KEK in Japan, to once again establish a new record for advanced network infrastructure performance.

"In addition to supporting network research on the scaling of TCP, Cisco also provided a wide variety of solutions, including Cisco Systems ONS 15540, Cisco ONS 15808, Cisco Catalyst 6500 Series, Cisco 7600 Series, and Cisco 12400 Series at the HEP sites in order for them to attain their goal. The Cisco next-generation 10 GE line cards deployed at SC2003 were part of the interconnect between the HEP sites of Caltech, SLAC, CERN, KEK/Japan, SURFnet, StarLight, and the CENIC network."

"Level 3 was pleased to support the SC2003 conference again this year," said Paul Fernes, director of business development for Level 3. "We've provided network services for this event for the past three years because we view the conference as a leading indicator of the next generation of scientific applications that distinguished researchers from all over the world are working diligently to unleash. Level 3 will continue to serve the advanced networking needs of the research and academic community, as we believe that we have a technologically superior broadband infrastructure that can help enable new scientific applications that are poised to significantly contribute to societies around the globe."

Cees de Laat, associate professor at the University of Amsterdam and organizer of the Global Lambda Integrated Facility (GLIF) Forum, added: "This world-scale experiment combined leading researchers, advanced optical networks, and network research sites to achieve this outstanding result. We were able to glimpse a yet-to-be explored network paradigm, where both shared and dedicated paths are exploited to map the data flows of big science onto a hybrid network infrastructure in the most cost-effective way. We need to develop a new knowledge base to use wavelength-based networks and Grids effectively, and projects such as UltraLight, TransLight, NetherLight, and UKLight, in which the team members are involved, have a central role to play in reaching this goal."

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About Caltech: With an outstanding faculty, including four Nobel laureates, and such off-campus facilities as the Jet Propulsion Laboratory, Palomar Observatory, and the W. M. Keck Observatory, the California Institute of Technology is one of the world's major research centers. The Institute also conducts instruction in science and engineering for a student body of approximately 900 undergraduates and 1,000 graduate students who maintain a high level of scholarship and intellectual achievement. Caltech's 124-acre campus is situated in Pasadena, California, a city of 135,000 at the foot of the San Gabriel Mountains, approximately 30 miles inland from the Pacific Ocean and 10 miles northeast of the Los Angeles Civic Center. Caltech is an independent, privately supported university, and is not affiliated with either the University of California system or the California State Polytechnic universities. http://www.caltech.edu

About SLAC: The Stanford Linear Accelerator Center (SLAC) is one of the world 's leading research laboratories. Its mission is to design, construct, and operate state-of-the-art electron accelerators and related experimental facilities for use in high-energy physics and synchrotron radiation research. In the course of doing so, it has established the largest known database in the world, which grows at 1 terabyte per day. That, and its central role in the world of high-energy physics collaboration, places SLAC at the forefront of the international drive to optimize the worldwide, high-speed transfer of bulk data. http://www.slac.stanford.edu/

About LANL: Los Alamos National Laboratory is operated by the University of California for the National Nuclear Security Administration of the U.S. Department of Energy and works in partnership with NNSA's Sandia and Lawrence Livermore National Laboratories to support NNSA in its mission. Los Alamos enhances global security by ensuring the safety and reliability of the U.S. nuclear weapons stockpile, developing technical solutions to reduce the threat of weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and national security concerns. http://www.lanl.gov/

About Netlab: Netlab is the Networking Laboratory at Caltech led by Professor Steven Low, where FAST TCP has been developed. The group does research in the control and optimization of protocols and networks, and designs, analyzes, implements, and experiments with new algorithms and systems. http://netlab.caltech.edu/FAST/

About CERN: CERN, the European Organization for Nuclear Research, has its headquarters in Geneva. At present, its member states are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland, and the United Kingdom. Israel, Japan, the Russian Federation, the United States of America, Turkey, the European Commission, and UNESCO have observer status. For more information, see http://www.cern.ch.

About DataTAG: The European DataTAG is a project co-funded by the European Union, the U.S. Department of Energy through Caltech, and the National Science Foundation. It is led by CERN together with four other partners. The project brings together the following European leading research agencies: Italy's Istituto Nazionale di Fisica Nucleare (INFN), France's Institut National de Recherche en Informatique et en Automatique (INRIA), the U.K.'s Particle Physics and Astronomy Research Council (PPARC), and the Netherlands' University of Amsterdam (UvA). The DataTAG project is very closely associated with the European Union DataGrid project, the largest Grid project in Europe also led by CERN. For more information, see http://www.datatag.org.

About StarLight: StarLight is an advanced optical infrastructure and proving ground for network services optimized for high-performance applications. Operational since summer 2001, StarLight is a 1 GE and 10 GE switch/router facility for high-performance access to participating networks and also offers true optical switching for wavelengths. StarLight is being developed by the Electronic Visualization Laboratory (EVL) at the University of Illinois at Chicago (UIC), the International Center for Advanced Internet Research (iCAIR) at Northwestern University, and the Mathematics and Computer Science Division at Argonne National Laboratory, in partnership with Canada's CANARIE and the Netherlands' SURFnet. STAR TAP and StarLight are made possible by major funding from the U.S. National Science Foundation to UIC. StarLight is a service mark of the Board of Trustees of the University of Illinois. See www.startap.net/starlight.

About the University of Manchester: The University of Manchester, located in the United Kingdom, was first granted a Royal Charter in April 1880 as the Victoria University and became the first of the U.K.'s great civic universities. As a full-range university it now has more than 70 departments involved in teaching and research, with more than 2,000 academic staff. There are more than 18,000 full-time students, including 2,500 international students, from over 120 countries studying for undergraduate and postgraduate level degrees. The University of Manchester has a proud tradition of innovation and excellence which continues today. Some of the key scientific developments of the century have taken place here. In Manchester, Rutherford conducted the research which led to the splitting of the atom and the world's first stored-program electronic digital computer, built by Freddie Williams and Tom Kilburn, successfully executed its first program in June 1948. The departments of Physics, Computational Science, Computer Science and the Network Group together with the E-Science North West Centre research facility are very active in developing a wide range of e-science projects and Grid technologies. See www.man.ac.uk.

About National LambdaRail: National LambdaRail (NLR) is a major initiative of U.S. research universities and private sector technology companies to provide a national scale infrastructure for research and experimentation in networking technologies and applications. NLR puts the control, the power, and the promise of experimental network infrastructure in the hands of the nation's scientists and researchers. Visit http://www.nationallambdarail.org for more information.

About CENIC: CENIC is a not-for-profit corporation serving California Institute of Technology, California State University, Stanford University, University of California, University of Southern California, California Community Colleges, and the statewide K-12 school system. CENIC's mission is to facilitate and coordinate the development, deployment, and operation of a set of robust multi-tiered advanced network services for this research and education community. http://www.cenic.org

About University of Amsterdam: The Advanced Internet Research group of the University of Amsterdam's Faculty of Science researches new architectures and protocols for the Internet. It actively participates in worldwide standardization organizations Internet Engineering Task Force and the Global Grid Forum. The group conducts experiments with extremely high-speed network infrastructures. The Institute carries out groundbreaking research in the fields of security, authorization, authentication and accounting for grid environments. The Institute is developing a virtual laboratory based on grid technology for e-science applications. For more information see http://www.science.uva.nl/research/air>www.science.uva.nl/research/air.

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Robert Tindol
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Gamma-Ray Bursts, X-Ray Flashes, and Supernovae Not As Different As They Appear

PASADENA, Calif.—For the past several decades, astrophysicists have been puzzling over the origin of powerful but seemingly different explosions that light up the cosmos several times a day. A new study this week demonstrates that all three flavors of these cosmic explosions--gamma-ray bursts, X-ray flashes, and certain supernovae of type Ic--are in fact connected by their common explosive energy, suggesting that a single type of phenomenon, the explosion of a massive star, is the culprit. The main difference between them is the "escape route" used by the energy as it flees from the dying star and its newly born black hole.

In the November 13 issue of the journal Nature, Caltech graduate student Edo Berger and an international group of colleagues report that cosmic explosions have pretty much the same total energy, but this energy is divided up differently between fast and slow jets in each explosion. This insight was made possible by radio observations, carried out at the National Radio Astronomy Observatory's Very Large Array (VLA), and Caltech's Owens Valley Radio Observatory, of a gamma-ray burst that was localized by NASA's High Energy Transient Explorer (HETE) satellite on March 29 of this year.

The burst, which at 2.6 billion light-years is the closest classical gamma-ray burst ever detected, allowed Berger and the other team members to obtain unprecedented detail about the jets shooting out from the dying star. The burst was in the constellation Leo.

"By monitoring all the escape routes, we realized that the gamma rays were just a small part of the story for this burst," Berger says, referring to the nested jet of the burst of March 29, which had a thin core of weak gamma rays surrounded by a slow and massive envelope that produced copious radio waves.

"This stumped me," Berger adds, "because gamma-ray bursts are supposed to produce mainly gamma rays, not radio waves!"

Gamma-ray bursts, first detected accidentally decades ago by military satellites watching for nuclear tests on Earth and in space, occur about once a day. Until now it was generally assumed that the explosions are so titanic that the accelerated particles rushing out in antipodal jets always give off prodigious amounts of gamma radiation, sometimes for hundreds of seconds. On the other hand, the more numerous supernovae of type Ic in our local part of the universe seem to be weaker explosions that produce only slow particles. X-ray flashes were thought to occupy the middle ground.

"The insight gained from the burst of March 29 prompted us to examine previously studied cosmic explosions," says Berger. "In all cases we found that the total energy of the explosion is the same. This means that cosmic explosions are beasts with different faces but the same body."

According to Shri Kulkarni, MacArthur Professor of Astronomy and Planetary Science at Caltech and Berger's thesis supervisor, these findings are significant because they suggest that many more explosions may go undetected. "By relying on gamma rays or X rays to tell us when an explosion is taking place, we may be exposing only the tip of the cosmic explosion iceberg."

The mystery we need to confront at this point, Kulkarni adds, is why the energy in some explosions chooses a different escape route than in others.

At any rate, adds Dale Frail, an astronomer at the VLA and coauthor of the Nature manuscript, astrophysicists will almost certainly make progress in the near future. In a few months NASA will launch a gamma-ray detecting satellite known as Swift, which is expected to localize about 100 gamma-ray bursts each year. Even more importantly, the new satellite will relay very accurate positions of the bursts within one or two minutes of initial detection.

The article appearing in Nature is titled "A Common Origin for Cosmic Explosions Inferred from Calorimetry of GRB 030329." In addition to Berger, the lead author, and Kulkarni and Frail, the other authors are Guy Pooley, of Cambridge University's Mullard Radio Astronomy Observatory; Vince McIntyre and Robin Wark, both of the Australia Telescope National Facility; Re'em Sari, associate professor of astrophysics and planetary science at Caltech; Derek Fox, a postdoctoral scholar in astronomy at Caltech; Alicia Soderberg, a graduate student in astrophysics at Caltech; Sarah Yost, a postdoctoral scholar in physics at Caltech; and Paul Price, a postdoctoral scholar at the University of Hawaii's Institute for Astronomy.

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Robert Tindol
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Aeronautical Lab Celebrates Its 75th

PASADENA, Calif. – It might seem a bit of a stretch to see what the flight control of a 747 and the way a boxfish maneuvers in very turbulent water have in common. But such thinking is all in a day's work within the walls of the California Institute of Technology's Graduate Aeronautical Laboratories (GALCIT), which this week celebrates its 75th anniversary.

It's fitting that GALCIT celebrates its 75th in the same year the world celebrates the 100th anniversary of flight. GALCIT's celebration will span two days, Friday and Saturday, November 14 and 15. On Friday there is an all-day symposium on solid mechanics and laboratory tours in the afternoon. On Saturday there will be presentations and a panel discussion on different aspects of aeronautical and astronautical research by various alumni and guests, followed by a banquet in the evening.

GALCIT was formally established in 1928 as the Guggenheim Aeronautical Laboratory by a donation from the Daniel Guggenheim Fund for the Promotion of Aeronautics. It was one of seven such donations made in the 1920s to advance the then-dismal state of aeronautical science in the United States. Its first director was Theodore von Kármán, one of the early scientific pioneers in aeronautics. Under his leadership, GALCIT became the birthplace of aeronautical research in Southern California. This led to the rapid development of the area's aeronautics industry in the 1930s, and ultimately to the modern aerospace industry. The original investment of the Guggenheim Foundation was the beginning of U.S. supremacy in aeronautics research, particularly for commercial and military aviation.

The most famous project of GALCIT was the establishment of the Jet Propulsion Laboratory (JPL), which today is the lead NASA institute for planetary exploration. It grew out of a combination of scholarly and popular interest in rocket propulsion. Beginning in 1935, GALCIT students and staff, including Frank Malina, A. M. O. Smith, H. S. Tsien, and W. Arnold, joined with two young explosives entrepreneurs, Jack Parsons and Ed Forman, to build and test rockets. The first long-duration solid propellant rocket motors and spontaneously ignitable liquid propellants were developed by the group. The solid propellants enabled the development of jet-assisted take-off rockets used in World War II and the founding of Aerojet Engineering Corporation, the first U.S. manufacturer of rocket engines. Ultimately, the liquid propellants were used in the Apollo program and the Titan missile. JPL was established as a separate organization in 1943 and now plays a key role in robotic activities in deep space and planetary exploration. The original concept of von Kármán was that GALCIT should be an institute in the European style that developed " . . . a tradition of research and teaching which stresses an appreciation for real applications in a very broad and deep base of fundamentals." Originally the application was strictly aeronautics, the development and operation of aircraft, and many contributions were made to aircraft structures, aerodynamics, and propulsion. But over the years the subject of aeronautics has been broadly interpreted to be "a wide discipline encompassing a broad spectrum of basic as well as applied problems in fluid dynamics and mechanics of materials." These days that's led to research into the study of fluid and solid mechanics, and the use of specialized large facilities like the Lucas Adaptive Wall Wind Tunnel, the supersonic shear layer facility, the free surface shear flow tunnel, the T5 hypervelocity shock tunnel, and the Ludwieg tube.

In addition, there are smaller laboratories to study cardiovascular fluid dynamics, combustion, and detonation. They also conduct numerical studies of vortex dynamics, turbulent mixing, fracture, the mechanics of materials, and shock waves.

All of which leads to the boxfish and the 747. It is just one specific example of the kind of work that goes on at GALCIT, and is part of the work of Morteza Gharib, the Hans W. Liepmann Professor of Aeronautics and Bioengineering at Caltech. Gharib believes the next wave of smart propulsion devices will be based on the biomechanics of flying and swimming. The goal, then, is to learn how nature engineers these things, with the hope of gleaning insight into the design of such aircraft as the 747. So one of the animals he studies is the humble boxfish, which is capable of staying within one millimeter of a sharp coral reef in highly turbulent water. It does this, Gharib notes, using "seven fins that are flapping and creating vortices here and there, keeping the fish right there, dead accurate."

Seventy-five years, and GALCIT is still learning.

For more information on the celebration and to register for events, please see http://www.galcit.caltech.edu/galcit75/.

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Caltech, JPL researchers unveil details on new type of light detector based on superconductivity

PASADENA, Calif.—A new and improved way to measure light has been unveiled by physicists at the California Institute of Technology and the Jet Propulsion Laboratory. The technology exploits the strange but predictable characteristics of superconductivity, and has a number of properties that should lead to uses in a variety of fields, from medicine to astrophysics.

Reporting in the October 23 issue of Nature, Caltech physicist Jonas Zmuidzinas and his JPL colleagues outline the specifications of their superconducting detector. The device is cleverly designed to sidestep certain limitations imposed by nature to allow for very subtle and precise measurements of electromagnetic radiation, which includes visible light, radio signals, X-rays, and gamma rays, as well as infrared and ultraviolet frequencies.

At the heart of the detector is a strip of material that is cooled to such a low temperature that electrical current flows unimpeded—in other words, a superconductor. Scientists have known for some time that superconductors function as they do because of electrons in the material being linked together as "Cooper pairs" with a binding energy just right to allow current to flow with no resistance. If the material is heated above a certain temperature, the Cooper pairs are torn apart by thermal fluctuations, and the result is electrical resistance.

Zmuidzinas and his colleagues have designed their device to register the slight changes that occur when an incoming photon—the basic unit of electromagnetic radiation—interacts with the material and affects the Cooper pairs. The device can be made sensitive enough to detect individual photons, as well as their wavelengths (or color).

However, a steady current run through the superconducting material is not useful for measuring light, so the researchers have also figured out a way to measure the slight changes in the superconductor's properties caused by the breaking of Cooper pairs. By applying a high-frequency microwave field of about 10 gigahertz, a slight lag in the response due to the Cooper pairs can be measured. In fact, the individual frequencies of the photons can be measured very accurately with this method, which should provide a significant benefit to astrophysicists, as well as researchers in a number of other fields, Zmuidzinas says.

"In astrophysics, this will give you lots more information from every photon you detect," he explains. "There are single-pixel detectors in existence that have similar sensitivity, but our new detector allows for much bigger arrays, potentially with thousands of pixels."

Such detectors could provide a very accurate means of measuring the fine details of the cosmic microwave background radiation (CMB). The CMB is the relic of the intense light that filled the early universe, detectable today as an almost uniform glow of microwave radiation coming from all directions.

Measurements of the CMB are of tremendous interest in cosmology today because of extremely faint variations in the intensity of the radiation that form an intricate pattern over the entire sky. These patterns provide a unique image of the universe as it existed just 300 thousand years after the Big Bang, long before the first galaxies or stars formed. The intensity variations are so faint, however, that it has required decades of effort to develop detectors capable of mapping them.

It was not until 1992 that the first hints of the patterns imprinted in the CMB by structure in the early universe were detected by the COBE satellite. In 2000, using new detectors developed at Caltech and JPL, the BOOMERANG experiment led by Caltech physicist Andrew Lange produced the first resolved images of the these patterns. Other experiments, most notably the Cosmic Background Imager of Caltech astronomer Tony Readhead, have confirmed and extended these results to even higher resolution. The images obtained by these experiments have largely convinced the cosmology research community that the universe is geometrically flat and that the theory of rapid inflation proposed by MIT physicist Alan Guth is a reality.

Further progress will help provide even more detailed images of the CMB—ideally, so detailed that individual fluctuations could be matched to primordial galaxies—as well as other information, including empirical evidence to determine whether the CMB is polarized. The new detector invented by Zmuidzinas and Henry G. LeDuc, a co-author of the paper, could be the breakthrough needed for the new generation of technology to study the CMB.

In addition, the new superconducting detector could be used to scan the universe for dark matter, and in X-ray astronomy for better analysis of black holes and other highly energetic phenomena, in medical scanning, in environmental science, and even in archaeology.

Other Caltech faculty are beginning to investigate these additional applications for the new detector. Assistant professor of physics Sunil Golwala is targeting dark-matter detection, while associate professor of physics and astronomy Fiona Harrison is pursuing X-ray astronomy applications.

The lead author of the paper is Peter Day, who earned his doctorate at Caltech under the direction of condensed-matter physicist David Goodstein and is now a researcher at JPL. In addition to LeDuc, also a researcher at JPL and leader of the JPL superconducting device group, the other authors are Ben Mazin and Anastasios Vayonakis, both Caltech graduate students working in Zmuidzinas's lab.

The work has been supported in part by NASA's Aerospace Technology Enterprise, the JPL Director's Research and Development Fund, the Caltech President's Fund, and Caltech trustee Alex Lidow.

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Caltech Boasts Silver Medal Winners at the 34th International Physics Olympiad

PASADENA, Calif.—The California Institute of Technology adds two silver medals to its list of distinguished honors, won by freshmen Emily Russell and Yernur Rysmagambetov, at the 34th International Physics Olympiad in Taiwan.

In addition to her silver medal, Russell was named "Best Female Participant" in the physics competition.

Russell, who is from Yorktown Heights, New York, is majoring in physics at Caltech. She is the recent recipient of both a Lingle and an Axline scholarship.

Caltech freshman Rysmagambetov, who also earned a silver medal in the competition, is originally from Kazakhstan and plans to major in computer science while at Caltech.

Day one of the rigorous two-day competition was devoted to solving complex theoretical physics problems including "A Swing of a Falling Weight," "A Piezoelectric Crystal Resonator under an Alternating Voltage," and "Neutrino Mass and Neutron Decay." After a day of rest, the next competition day consisted of solving five-hour experimental problems utilizing laser beams or diodes, photodetectors, multimeters, and nematic liquid crystal.

At this year's International Physics Olympiad, 238 students from 54 countries participated. Originating in 1967 in Warsaw, this is the major international physics competition for secondary school students. Every year the competition is held in a different country around the world. Next year's 2004 competition will be held in July in Pohang, South Korea.

Contact: Deborah Williams-Hedges (626) 395-3227 debwms@caltech.edu

Visit the Caltech Media Relations Web site at: http://pr.caltech.edu/media

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A Detailed Map of Dark Matter in a Galactic Cluster Reveals How Giant Cosmic Structures Formed

Astrophysicists have had an exceedingly difficult time charting the mysterious stuff called dark matter that permeates the universe because it's--well--dark. Now, a unique "mass map" of a cluster of galaxies shows in unprecedented detail how dark matter is distributed with respect to the shining galaxies. The new comparison gives a convincing indication of how dark matter figures into the grand scheme of the cosmos.

Using a technique based on Einstein's theory of general relativity, an international group of astronomers led by Jean-Paul Kneib, Richard Ellis, and Tommaso Treu of the California Institute of Technology mapped the mass distribution of a gigantic cluster of galaxies about 4.5 billion light-years from Earth. They did this by studying the way the cluster bends the light from other galaxies behind it. This technique, known as gravitational lensing, allowed the researchers to infer the mass contribution of the dark matter, even though it is otherwise invisible.

Clusters of galaxies are the largest stable systems in the universe and ideal "laboratories" for studying the relationship between the distributions of dark and visible matter. Caltech's Fritz Zwicky realized in 1937 from studies of the motions of galaxies in the nearby Coma cluster that the visible component of a cluster--the stars in galaxies--represents only a tiny fraction of the total mass. About 80 to 85 percent of the matter is invisible.

In a campaign of over 120 hours of observations using the Hubble Space Telescope, the researchers surveyed a patch of sky almost as large as the full moon, which contained the cluster and thousands of more distant galaxies behind it. The distorted shapes of these distant systems were used to map the dark matter in the foreground cluster. The study achieved a new level of precision, not only for the center of the cluster, as has been done before for many systems, but also for the previously uncharted outlying regions.

The result is the most comprehensive study to date of the distribution of dark matter and its relationship to the shining galaxies. Signals were traced as far out as 15 million light-years from the cluster center, a much larger range than in previous investigations.

Many researchers have tried to perform these types of measurements with ground-based telescopes, but the technique relies heavily on measuring the exact shapes of distant galaxies behind the cluster, and for this the "surgeon's eye" of the Hubble Space Telescope is far superior.

The study, to be published soon in the Astrophysical Journal, reveals that the density of dark matter falls fairly sharply with distance from the cluster center, defining a limit to its distribution and hence the total mass of the cluster. The falloff in density with radius confirms a picture that has emerged from detailed computer simulations over the past years.

Team member Richard Ellis said, "Although theorists have predicted the distribution of dark matter in clusters from numerical simulations based on the effects of gravity, this is the first time we have convincing observations on large scales to back them up.

"Some astronomers had speculated clusters might contain large reservoirs of dark matter in their outermost regions," Ellis added. "Assuming our cluster is representative, this is not the case."

In finer detail, the team noticed that some structure emerged from their map of the dark matter. For example they found localized concentrations of dark matter associated with galaxies known to be slowly falling into the system. Overall there is a striking correspondence between features in the dark matter map and that delineated by the cluster galaxies, which is an important result in the new study.

"The close association of dark matter with structure in the galaxy distribution is convincing evidence that clusters like the one studied built up from the merging of smaller groups of galaxies, which were prevented from flying away by the gravitational pull of their dark matter," says Jean-Paul Kneib, who is the lead author in the publication.

Future investigations will extend this work using Hubble's new camera, the Advanced Camera for Surveys (ACS), which will be trained on a second cluster later this year. ACS is 10 times more efficient than the Wide Field and Planetary Camera 2, which was used for this investigation. With the new instrument, it will be possible to study clumps of finer mass in galaxy clusters in order to investigate how the clusters originally were assembled.

By tracing the distribution of dark matter in the most massive structure in the universe using the powerful trick of gravitational lensing, astronomers are making great progress towards a better understanding of how such systems were assembled, as well as toward defining the key role of dark matter.

In addition to Kneib, Ellis, and Treu, the other team members are Patrick Hudelot of the Observatoire Midi-Pyrénées in France, Graham P. Smith of Caltech, Phil Marshall of the Mullard Radio Observatory in England, Oliver Czoske of the Institut für Astrophysik und Extraterrestrische Forschung in Germany, Ian Smail of the University of Durham in England, and Priya Natarajan of Yale University.

For more information, please contact:

Jean-Paul Kneib Caltech/Observatoire Midi-Pyrénées (currently in Hawaii) Phone: (808) 881-3865 E-mail: jean-paul.kneib@ast.obs-mip.fr

Richard Ellis Caltech Phone: (626) 395-4970 (secretary) (Australia: Cellular: 011-44-7768-923277) E-mail: rse@astro.caltech.edu

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International Teams Set New Long-range Speed Record with Next-generation Internet Protocol

Scientists at the California Institute of Technology (Caltech) and the European Organization for Nuclear Research (CERN) have set a new Internet2 land speed record using the next-generation Internet protocol IPv6. The team sustained a single stream TCP rate of 983 megabits per second for more than one hour between the CERN facility in Geneva and Chicago, a distance of more than 7,000 kilometers. This is equivalent to transferring a full CD in 5.6 seconds.

The performance is remarkable because it overcomes two important challenges:

· IPv6 forwarding at Gigabit-per-second speeds · High-speed TCP performance across high bandwidth/latency networks.

This major step towards demonstrating how effectively IPv6 can be used should encourage scientists and engineers in many sectors of society to deploy the next-generation Internet protocol, the Caltech researchers say.

This latest record by Caltech and CERN is a further step in an ongoing research-and-development program to develop high-speed global networks as the foundation of next generation data-intensive grids. Caltech and CERN also hold the current Internet2 land speed record in the IPv4 class, where IPv4 is the traditional Internet protocol that carries 90 percent of the world's network traffic today. In collaboration with the Stanford Linear Accelerator Center (SLAC), Los Alamos National Laboratory, and the companies Cisco Systems, Level 3, and Intel, the team transferred one terabyte of data across 10,037 kilometers in less than one hour, from Sunnyvale, California, to Geneva, Switzerland. This corresponds to a sustained TCP rate of 2.38 gigabits per second for more than one hour.

Multi-gigabit-per-second IPv4 and IPv6 end-to-end network performance will lead to new research and business models. People will be able to form "virtual organizations" of planetary scale, sharing in a flexible way their collective computing and data resources. In particular, this is vital for projects on the frontiers of science and engineering, projects such as particle physics, astronomy, bioinformatics, global climate modeling, and seismology.

Harvey Newman, professor of physics at Caltech, said, "This is a major milestone towards our dynamic vision of globally distributed analysis in data-intensive, next-generation high-energy physics (HEP) experiments. Terabyte-scale data transfers on demand, by hundreds of small groups and thousands of scientists and students spread around the world, is a basic element of this vision; one that our recent records show is realistic. IPv6, with its increased address space and security features is vital for the future of global networks, and especially for organizations such as ours, where scientists from all world regions are building computing clusters on an increasing scale, and where we use computers including wireless laptop and mobile devices in all aspects of our daily work.

"In the future, the use of IPv6 will allow us to avoid network address translations (NAT) that tend to impede the use of video-advanced technologies for real-time collaboration," Newman added. "These developments also will empower the broader research community to use peer-to-peer and other advanced grid architectures in support of their computationally intensive scientific goals."

Olivier Martin, head of external networking at CERN and manager of the DataTAG project said, "These new records clearly demonstrate the maturity of IPv6 protocols and the availability of suitable off-the-shelf commercial products. They also establish the feasibility of transferring very large amounts of data using a single TCP/IP stream rather than multiple streams as has been customarily done until now by most researchers as a quick fix to TCP/IP's congestion avoidance algorithms. I am optimistic that the various research groups working on this issue will now quickly release new TCP/IP stacks having much better resilience to packet losses on long-distance multi-gigabit-per-second paths, thus allowing similar or even better records to be established across shared Internet backbones."

The team used the optical networking capabilities of the LHCnet, DataTAG, and StarLight and gratefully acknowledges support from the DataTAG project sponsored by the European Commission (EU Grant IST-2001-32459), the DOE Office of Science, High Energy and Nuclear Physics Division (DOE Grants DE-FG03-92-ER40701 and DE-FC02-01ER25459), and the National Science Foundation (Grants ANI 9730202, ANI-0230967, and PHY-0122557).

About the California Institute of Technology (Caltech):

With an outstanding faculty, including four Nobel laureates, and such off-campus facilities as Palomar Observatory, and the W. M. Keck Observatory, the California Institute of Technology is one of the world's major research centers. The Institute also conducts instruction in science and engineering for a student body of approximately 900 undergraduates and 1,000 graduate students who maintain a high level of scholarship and intellectual achievement. Caltech's 124-acre campus is situated in Pasadena, California, a city of 135,000 at the foot of the San Gabriel Mountains, approximately 30 miles inland from the Pacific Ocean and 10 miles northeast of the Los Angeles Civic Center. Caltech is an independent, privately supported university, and is not affiliated with either the University of California system or the California State Polytechnic universities. More information is available at http://www.caltech.edu.

About CERN:

CERN, the European Organization for Nuclear Research, has its headquarters in Geneva, Switzerland. At present, its member states are Austria, Belgium, Bulgaria, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland, and the United Kingdom. Israel, Japan, the Russian Federation, the United States of America, Turkey, the European Commission, and UNESCO have observer status. For more information, see http://www.cern.ch.

About the European Union DataTAG project:

The DataTAG is a project co-funded by the European Union, the U.S. Department of Energy, and the National Science Foundation. It is led by CERN together with four other partners. The project brings together the following European leading research agencies: Italy's Istituto Nazionale di Fisica Nucleare (INFN), France's Institut National de Recherche en Informatique et en Automatique (INRIA), the UK's Particle Physics and Astronomy Research Council (PPARC), and Holland's University of Amsterdam (UvA). The DataTAG project is very closely associated with the European Union DataGrid project, the largest grid project in Europe also led by CERN. For more information, see http://www.datatag.org.

 

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