Дата: 24 апреля 1998 (1998-04-24)
От: Alexander Bondugin
Тема: Chabrow Report To Be Available On The NASA Home Page
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Michael Braukus
Headquarters, Washington, DC April 23, 1998
(Phone: 202/358-1979)
NOTE TO EDITORS: N98-29
CHABROW REPORT TO BE AVAILABLE ON THE NASA HOME PAGE
The cost assessment and validation task force, an
independent committee chaired by Jay Chabrow, has completed its
report on the International Space Station. The complete report
will be available electronically this afternoon.
In September 1997, NASA Administrator Daniel S. Goldin
asked Jay Chabrow to establish a task force for the independent
review and assessment of costs, budgets and partnership
performance on the International Space Station program and to
provide advice and recommendations to the NASA Advisory Council.
The objective of this activity was to provide advice and
recommendations for cost-effective modifications to the present
business structure and cost management practices of the program,
and to determine the total cost over the life of the program.
Media can review a copy of the report after noon EDT in
the NASA newsrooms at NASA Headquarters, Washington, DC; Johnson
Space Center, Houston, TX; Marshall Space Flight Center,
Huntsville, AL; and Kennedy Space Center, FL. At 2 pm EDT the
report will be available on the NASA Home Page at URL:
http://www.nasa.gov/cavtf/index.html
- end -
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Дата: 24 апреля 1998 (1998-04-24)
От: Alexander Bondugin
Тема: Starry dream in Chile to become high-tech telescope reality [1/2]
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University of North Carolina-Chapel Hill
Contacts: Karen Stinneford, Mike McFarland, Karen Moon
For immediate use: April 15, 1998 -- No. 335
Starry dream in Chile to become high-tech telescope reality
By KAREN STINNEFORD, UNC-CH News Services
CHAPEL HILL -- One small shovel of dirt, one giant leap for astronomers.
When officials in Cerro Pachon, Chile, ceremonially break ground for the
new SOAR telescope Friday (April 17), a 12-year-old dream among research
astronomers at the University of North Carolina at Chapel Hill will become a
reality.
"We are so excited," said Dr. Wayne Christiansen, physics and astronomy
professor and director of the Morehead Observatory. "It's finally going to
happen."
SOAR, the Southern Observatory for Astrophysical Research, is a
state-of-the-art, lightweight, computer-controlled, 4-meter telescope that
will sit atop Cerro Pachon, a 9,000-foot mountain in Chile's northern
Andes. The $28-million research facility is being funded by four partners:
UNC-CH, Michigan State University, the U.S. National Optical Astronomy
Observatories (NOAO) and the country of Brazil. Construction should be
completed by 2001.
UNC-CH representatives who shovel Chilean earth Friday at 11:30 a.m. EDT
will do more than turn over a little dirt. They literally will help usher in
a new era of science.
"The SOAR telescope will allow Carolina researchers and their collaborators
to make significant contributions to the worldwide astronomy community well
into the next century," said Chancellor Michael Hooker. "As a result,
Carolina can better attract the best and brightest investigators and
teachers, and greatly advance the cause of knowledge among scientists,
students and the general public. "Our faculty have dreamed about SOAR for a
long time, and we are deeply grateful for the assistance of Sen. Lauch
Faircloth, Rep. David Price and the Cato and Goodman families in making that
bold vision a reality."
UNC-CH is contributing $8 million toward the project, $6 million of which
came from the U.S. Department of Defense. Faircloth, R-N.C., led efforts by
the N.C. congressional delegation to inform lawmakers about the project,
which led to the first of two $3-million appropriations. Price also has been
a strong supporter of SOAR. The rest of UNC-CH's share is coming from
private donations.
On Friday, representatives from UNC-CH, Michigan State, Brazil and NOAO will
speak and erect flags from their institutions or country. UNC-CH physics and
astronomy faculty attending include Dr. Thomas Clegg, department chair, and
Drs. Bruce Carney, Charles Evans, Robert McMahan and Gerald Cecil. Cecil is
on leave to NOAO in Tucson, Ariz., leading SOAR's scientific design team.
Dr. Walter Bollenbacher from biology also will be part of the Carolina
delegation.
Carney will symbolically lift to the skies the lens from UNC-CH's first
telescope, purchased in England by UNC President Joseph Caldwell in 1824.
Seven years later in Chapel Hill, Caldwell oversaw construction of the first
astronomical observatory at a U.S. university. SOAR will collect 3,400 times
more light than that original telescope, Carney said.
"We will detect objects well over a billion times fainter than the eye can
see, and about 20 million times fainter than did that first telescope,"
Carney said. "So we can see dimmer objects and stars out to vastly greater
distances, and, hence, further back in time than was possible in Caldwell's
day."
UNC-CH alumni connections will place Edgar and Samantha Cato of Charlotte
and Leonard Goodman of New York City at the ceremony. The Cato and Goodman
families contributed early and generously to SOAR. Accompanying Goodman will
be his son, Stanley; daughter-in-law, Nancy; and grandchildren Yale and
Pace. Besides supporting SOAR, the Goodman family is funding a laboratory in
Phillips Hall to be named for Dr. Abraham Goodman. UNC-CH is recruiting an
astronomical instrument builder to work in the lab developing instruments
for SOAR and other telescopes.
SOAR is not just your average telescope. Recent advances in equipment design
and computer technology mean SOAR will allow astronomers to study and learn
in ways they only dreamed possible, Christiansen said.
For starters, SOAR's location is ideal. Based in the foothills of the
20,000-foot Andes mountain range, SOAR sits far away from smog, lights and
other visual distractions generated by city life. The flowing offshore winds
and lack of annual rainfall are just right for optimal viewing, Christiansen
said.
"The seeing is superb," he said. "In Chile, the center of the Milky Way
galaxy passes right over your head. You can observe it for a much longer
period of time, and your images aren't distorted as much by atmospheric
effects."
Chile is the best site in the Southern Hemisphere for viewing the Milky Way,
the galaxy containing Earth and the other planets in our solar system, and
the Magellanic Clouds, the closest neighboring galaxy.
Besides offering an unfettered view of the universe, SOAR will be a
technological marvel compared with today's telescopes, Christiansen said.
SOAR will deliver the highest quality images possible with a large,
ground-based telescope.
A major advance will be SOAR's "quick change" instruments. Currently,
4-meter telescopes -- such as NOAO's Blanco telescope on the neighboring
Chilean mountain, Cerro Tololo -- use equipment weighing tons. Depending on
what type of equipment an astronomer needs to view the universe, such as
infrared or visual cameras or spectographs, it can take a day or more to
change settings and tools.
In 1987, Christiansen flew to Chile to spend five days on the Blanco
telescope, which had been set up, per his grant request submitted months
earlier, for visual observation. Just before he left town, however, a
supernova blew up, making national news.
"Ironically, though, when I got to the observatory, which had the best
equipment in the world to view this supernova, I couldn't even look at it,"
Christiansen said. "If we had pointed the telescope at the supernova, we
would have fried the insides."
The rare supernova was too bright for the Blanco telescope's sensitive
visual equipment. Yet, changing equipment would have taken a day -- a big
part of Christiansen's allotted time on the telescope. So Christiansen stuck
with his original research plan and later viewed the supernova with a small
telescope, like thousands of backyard astronomers.
That scenario won't happen with SOAR. Thanks to improved design, lightweight
equipment and computerized remote controls, SOAR can "quick change,"
allowing researchers to respond immediately to astronomical phenomena when
they happen.
"With SOAR, the minute something like a supernova comes up, we'll be all
over it," Christiansen said. "We'll be able to react to unexpected events
when they happen."
Because it is so cumbersome to change equipment on telescopes like the
Blanco, researchers now sign up for the telescope in several-day intervals.
This isn't always the best use of time, for the researcher or the telescope.
For example, Carney studies pulsating stars. The current system means he
travels to Chile, collects five days worth of data and then returns to
UNC-CH with reams of numbers to crunch.
"It's an enormous amount of work for Bruce," Christiansen said. "Because of
his area of expertise, what he really needs are several 15-minute intervals
on the telescope throughout the evening -- not five days at a time. The
current system won't allow that. SOAR will."
SOAR's advanced computer system will allow UNC-CH researchers to study the
skies from Chapel Hill. Because the university is guaranteed time on SOAR,
researchers will create a list of projects and astronomical conditions, such
as dark of the moon, needed to see them. When the right conditions happen,
researchers will be notified to log onto computers in Chapel Hill to
download data in real time.
"We'll get our first cut at science right away and if things aren't going as
expected, you can switch filters or make other changes on the fly,"
Christiansen said. "Once you've finished, you can get your data over the
Internet or by airmail for further analysis. For the most part, we won't
need to go to Chile."
However, graduate students will be encouraged to visit the SOAR site. Not
only will they gain valuable hands-on experience working with a
state-of-the-art telescope, Christiansen said, but they'll have a chance to
work alongside some of the world's most renowned astronomers.
"It is a great experience when graduate students can work as colleagues with
visiting scientists," he said. "These informal arrangements pay huge
dividends for students, and we think it is a critical learning experience
for them."
SOAR will cost about $800,000 annually to operate, which NOAO has agreed to
fund in exchange for time on the telescope. NOAO also will provide engineers
and technicians on site to operate SOAR as directed by the project's
partners. Brazil will contribute half of the $28 million construction costs;
Michigan State will contribute $6 million.
For its $8 million contribution, UNC-CH astronomers will use SOAR about 60
days each year. "This is time we control, time in which we set the
priorities as a group," Christiansen said.
There's an important public service component to SOAR, as well. Christiansen
and his colleagues are looking at two exciting ways to involve North
Carolina public-school teachers and students in the science of SOAR.
First, Tar Heel teachers and students can view some of the same astronomical
objects UNC-CH researchers see -- such as pulsating stars in the Milky Way
galaxy and beyond, or newly discovered comets or asteroids, Christiansen
said. UNC-CH astronomers will post interesting phenomena on a computer
server in Chapel Hill; these images then can be seen in classrooms via
Internet, he said.
Second, science teachers and students can submit proposals for SOAR
projects. UNC-CH researchers will review them and choose some; requested
information will be downloaded to the school classroom, where it can be
accessed by computer, Christiansen said.
"We are committed to opening the world of science to our public schools in
as many ways possible," Christiansen said. "We know, as educators, that
having an opportunity to learn science hands-on only fuels a student's
interest and desire to learn."
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Дата: 24 апреля 1998 (1998-04-24)
От: Alexander Bondugin
Тема: Columbia University Unveils Supercomputer That Will Simulate Birth Of
Subject: Columbia University Unveils Supercomputer That Will Simulate Birth Of
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Office of Public Affairs
Columbia University
Contact: Bob Nelson
rjn2@columbia.edu
(212) 854-6580
April 21, 1998
Columbia Unveils Supercomputer That Will Simulate Birth Of The Universe
Machine Capable Of 400 Billion Calculations Per Second To Explore
Trillion-Degree Conditions That Existed As Time Began
Physicists at Columbia University have constructed one of the world's
fastest supercomputers, one that can perform 400 billion calculations
per second to simulate the three-trillion-degree conditions that
existed at the birth of the universe, when the components of atomic
nuclei boiled free into a ultra-hot plasma.
The supercomputer, dubbed QCDSP, is the latest in a series of relatively
inexpensive parallel supercomputers now in use at universities around
the world that have been built at Columbia, in what has become a
burgeoning cottage industry for the physics department. Run in tandem
with a sister machine capable of 600 billion operations per second
Columbia is also finishing at Brookhaven National Laboratories on
Long Island, the supercomputer will be capable of peak performance
At trillion-calculation-per-second levels at a cost of less than $4
million, less than a tenth the typical $50 million price tag for a
commercial supercomputer with that speed. Comparable, but far more
expensive, machines are operating at the National Security Agency,
Fort Meade, Md.; Sandia National Laboratories, Sandia, N.M., and at
Tsukuba University in Japan. A billion floating-point operations, or
adds and multiplies, per second is commonly called a gigaflop; a
trillion such operations is a teraflop!
The Columbia machine's vast computing power, which with others of
its generation offers a 30-fold improvement over the previous
generation of supercomputers, is needed to simulate the
interactions between quarks and gluons, the tiny constituents of
neutrons and protons, predicted by quantum chromodynamics (QCD)
theory. Physicists believe that when normal matter is heated to
three trillion degrees Fahrenheit, quarks and gluons -- never
before observed outside an atomic nucleus -- boil free into an
ultra-hot gas, called a quark-gluon plasma. The supercomputer will
simulate this state, which scientists believe existed at the time
of the Big Bang, perhaps 10 billion years ago, and hope to
recreate at a particle accelerator under construction at
Brookhaven.
"These computers should be able to make major contributions to our
understanding of the properties of the known strongly interacting
particles, allowing accurate calculation of particle masses and
decay rates," said Norman Christ, chairman and professor of
physics and one of the project's principal investigators. "By
building them ourselves, we're able to acquire world-class
machines at a price within the level of funding available to U.S.
science."
The Columbia supercomputer will also be used to simulate
interactions within atomic nuclei under other conditions, and
could if necessary be programmed to carry out any of a number of
highly complex calculations in fields such as weather forecasting,
plasma physics and oil exploration. The only requirements in
parallel supercomputing are that the problem be divisible among a
large number of processors and that the data to be exchanged
between these parts of the calculation be routed only between
neighboring processors.
Such huge computing power can be obtained at such a low cost
because of a series of design decisions made by Professor Christ's
research group, which pioneered the construction of highly
parallel supercomputers dedicated to QCD calculations in 1982. The
supercomputer alone incorporates 8,192 individual nodes that are
linked together to undertake computations in parallel rather than
sequentially. Each node includes a communications controller,
designed by Columbia physicists and built to their specifications,
and a digital signal processor (DSP) manufactured by Texas
Instruments, both mounted on a circuit board with 2 megabytes of
memory. A combination of the physics topic and the type of
processor used led to the supercomputer's name: QCDSP.
The Texas Instruments DSP is a unique choice of fast, inexpensive
processor; no parallel computer with even a tenth as many of the
processors has ever been constructed. Every node, or daughter
board -- processor plus controller -- is a computer in its own
right, with the computational performance of a Pentium PC but
simplified to cost $80 and fit on a circuit board that measures
1-3/4 by 2-1/2 inches.
A mother board holds 64 of the daughter boards, and a portable
crate holds 8 mother boards. Crates can be cabled together using a
four-dimensional mesh of communications wires to create even
larger computers. Adding a host workstation to talk to the machine
completes the computer, since all other required circuits are
supplied in each crate.
Smaller machines built by the physics department's staff are at
work at other universities: a 50-gigaflop computer at Florida
State University, a 6-gigaflop machine at Ohio State University
and a 3-gigaflop machine at the University of Wuppertal in
Germany, all built within the last year. Professor Christ said he
would prefer to license the technology to a computer company that
would build the machines, rather than tie up the department's
staff with such projects.
The other principal investigators in Professor Christ's research
group are Robert Mawhinney, associate professor of physics, who
has developed a UNIX-like operating system, called QOS, for the
supercomputers, and Alan Gara, associate research scientist, who
has played a leading role in designing the supercomputers. Pavlos
Vranas, a postdoctoral fellow, has been instrumental in creating
the code that carries out the actual physics calculations on the
machines. One former undergraduate and a number present or former
physics Ph.D. students have made major contributions to the
project, in addition to collaborators at the Columbia University's
Nevis Labs, Fermilab, Florida State University, Trinity College
Dublin and Ohio State University.
Quarks and gluons, also known as strongly interacting particles,
are the least understood elements of the Standard Model, the
prevailing physics theory that relates all known or predicted
forces and particles. Quarks and gluons are so tightly bound that
they have never been observed outside atomic nuclei. Physicists
have thus turned to numerical simulations to study them, an
approach that has demonstrated properties -- such as the
impossibility of producing isolated quarks or gluons -- that could
only be guessed from experiment.
Creating a quark-gluon plasma is one of the principal goals of the
Relativistic Heavy Ion Collider being constructed at Brookhaven
and due for completion next year. Until experimental efforts to
create this quark-gluon plasma are successful, large-scale
numerical simulations are the only source of information about the
new form of matter, Professor Christ said. The numerical approach
to the study of nuclear forces was invented nearly 25 years ago
and is now an active segment of theoretical particle physics.
With the new Columbia and Tsukuba machines and a similar project
in Rome, physicists expect dramatic progress in quantum
chromodynamics theory. The increased capacity allows more complete
and realistic QCD calculations and thus more precise tests of the
theory and more accurate predictions of as-yet unobserved
phenomena, such as the quark-gluon plasma. But even more exciting,
Professor Christ said, is that this level of computer resources
will allow computer experiments that explore new schemes for
combining Einstein's relativity and quantum mechanics to create a
unified physics theory, what some physicists call a "theory of
everything."
"Such new quantum field theories may show further unexpected
behavior that could provide clues to the origin of the Standard
Model and examples of what may lie beyond it," Professor Mawhinney
said.
Funding for the computers, and the Relativistic Heavy Ion
Collider, has been provided by the Department of Energy. The
Japanese Institute of Physical and Chemical Research, known by its
Japanese acronym, RIKEN, has agreed to contribute $20 million to
equip the Brookhaven collider to study high-energy protons, a key
element in QCD theory. A description of the QCDSP can be found at
http://phys.columbia.edu/~cqft.
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Дата: 24 апреля 1998 (1998-04-24)
От: Alexander Bondugin
Тема: Astronomers Will Monitor A 'Diamond In The Sky'
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News Service
Iowa State University
Contact:
Steve Kawaler, Physics and Astronomy, (515) 294-9728
Skip Derra, News Service, (515) 294-4917
April 20, 1998
ASTRONOMERS WILL MONITOR A 'DIAMOND IN THE SKY'
AMES, Iowa -- A team of about 50 astronomers will train their
telescopes on a relatively close pulsating white dwarf star for
the next three weeks with the goal of possibly finding a true gem
in the sky. The astronomers, led by Steve Kawaler, an Iowa State
University professor of physics and astronomy, will be monitoring
a vibrating white dwarf star designated BPM37093, which is 17
light years from Earth. (A light year is the distance light
travels in a year, about 6 trillion miles).
The astronomers will make their observations using the Whole Earth
Telescope and the Hubble Space Telescope from April 17 to May 4.
Their findings could have an impact on the age of our galaxy and
of the universe, and become the delight of gemologists worldwide.
"We think BPM37093 is primarily made up of carbon and oxygen in a
crystallized state," Kawaler says. "That would make it a diamond
with a blue-green tint. It's estimated carat weight is 1034, or 10
billion trillion trillion. This truly could be a diamond in the
sky."
BPM37093 is a slowly cooling remnant of a star that once was a
little more massive than our Sun. It resides in the constellation
of Centaurus and is clearly viewable only from the Southern
Hemisphere. Understanding the properties of white dwarf stars is
important because nearly all stars will become eternally cooling
white dwarf stars. Only the most massive stars will become fiery
exploding supernovas.
Being a white dwarf star, Kawaler said, BPM37093 has burned its
nuclear fuel and all that remains is ash of carbon and oxygen. The
only other known partially solid stars are neutron stars.
By measuring the vibration frequency of BPM37093, astronomers can
sneak a peak into its interior. Through stellar seismological
techniques, Kawaler and the team of astronomers will attempt to
ascertain the makeup of BPM37093.
"The pulsations will tell us what's going on inside a star the
same way earthquakes tell us about the inside of Earth," Kawaler
said. "Each of the white dwarf's various brightness changes tells
us something unique about the star's interior. It is very much
like being able to hear and identify a violin and a bassoon in an
orchestra concert."
Crystallized white dwarf stars have been theorized to exist for 30
years, but because these stars are rare and exist under very
extreme conditions, proving their existence has been a challenge.
"Here on Earth, we will never be able to experience the types of
pressures on the interiors of these stars," Kawaler said. "It's
been a theory for 30 years, but it never has been tested. A white
dwarf is a very, very dense star. One teaspoon of matter from
these stars weigh as much as the New York Yankee infield -- about
500,000 grams."
To make the critical measurements of the star, Kawaler's group
will use a modern-day armada of Earth-based telescopes, which are
part of the Whole Earth Telescope (WET). WET telescopes in South
Africa, Brazil, Chile, New Zealand and Australia will be used in
the observations. These measurements will be coupled with highly
sensitive measurements from the orbiting Hubble Space Telescope.
Kawaler is director of WET, which has partners at 22 observatories
around Earth and allows 24-hour monitoring of stars. WET is
headquartered at Iowa State University and is a program of the
International Institute of Theoretical and Applied Physics.
The core observation run will be April 20-29. During this time,
the Hubble Space Telescope will turn its attention to BPM37093 and
provide the astronomers with highly sensitive measurements in
ultraviolet and optical wavelengths. Kawaler says the Hubble will
allow astronomers to determine the precise pattern of vibrations
on BPM37093, while the WET observations will provide the precise
timing of the vibrations.
The astronomers plan to continue to monitor the white dwarf star
periodically for several years. They also hope to pin down how the
crystallization happens and determine if BPM37093 is a "solid
diamond or a diamond shell with oxygen snow," Kawaler said.
"The material that is crystallizing is a mixture of different
elements," Kawaler explained. "Different elements crystallize at
different temperatures. Heavier elements like oxygen crystallize
first, then the carbon will crystallize. If oxygen crystallizes in
a gas of carbon, then those crystalline nuggets may sink to the
center of the star -- as if it were snowing."
The snowing effect would create additional energy not accounted
for in some current white dwarf star models, Kawaler said. "But if
the oxygen crystallizes and stays suspended, then you're getting
crystallization without an additional energy source. If it snows,
you'll have an oxygen crystalline core and a carbon crystal
mantle. Sort of a diamond shell."
And if the astronomers detect a shell with snow, then cool white
dwarf stars (the oldest stars in this part of the galaxy) are
older than previously thought.
A pulsating white dwarf star that is snowing inside will be
roughly 11 to 12 billion years old, rather than the currently
estimated 9 billion years, Kawaler said. This finding will extend
the lower limit of the age of the Milky Way galaxy and, in turn,
extend the estimated age of the universe.
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