Category: Observatories

Image credit: Caltech

The terrible wild fires in Southern California have destroyed thousands of homes, killed more than 16 people and are still out of control in many areas. The Palomar observatory is in the area, but its operators feel that the 200-inch telescope isn’t at risk. The observatory was built with two layers of concrete and steel, dead trees and underbrush have been removed from a significant area, and it boasts a large water tank and volunteer fire fighting team. Smoke and ash have put a temporary halt to observations, though.

The tragic fires that continue to affect San Diego County remind us all just how fragile life and property can be. Currently fires are slowly approaching the area of Palomar Mountain, home to the California Institute of Technology’s historic Palomar Observatory.

Smoke and ash from the fires have put a temporary end to the Observatory’s nightly observations, but the Observatory itself is not threatened. In fact the dome of the 200-inch telescope is a safe place for and has been selected as an evacuation point for the Palomar Mountain Community .

“The builders of Palomar realized the potential fire danger and designed the 200-inch Hale Telescope to survive a fire. It is constructed with two layers of concrete and steel. Also, in recent months our maintenance staff along with foresters have removed dead and dying trees from the Observatory grounds. We are prepared for the worst,” says Palomar Observatory’s superintendent, Bob Thicksten. It doesn’t hurt that the Observatory has its own million gallon water tank, an array of fire hydrants and staff members who double as volunteer firefighters as well. Thicksten has worked tirelessly to maintain a working relationship with the local fire department, the United States Forest Service and the California Department of Forestry (CDF), which has its own fire station less than half a mile from the Observatory’s main gate.

The Palomar Observatory will issue further press statements as necessary.

Original Source: Palomar Observatory

Image credit: Fermilab

The 100th detector for the Pierre Auger Observatory was recently completed, making the array the world’s largest cosmic ray detector. It consists of surface detectors spread out over 181 square kilometers of land in Argentina. Once it’s working, the detector should be able to capture some of the most energetic cosmic ray particles – they only strike a 2.5 square kilometer area once a year. The mystery with these high-energy particles is that astronomers have no idea what in the Universe could create them. The long term plans for the observatory is to eventually have 1,600 detectors by 2005.

With the completion of its hundredth surface detector, the Pierre Auger Observatory, under construction in Argentina, this week became the largest cosmic-ray air shower array in the world. Managed by scientists at the Department of Energy’s Fermi National Accelerator Laboratory, the Pierre Auger project so far encompasses a 70-square-mile array of detectors that are tracking the most violent-and perhaps most puzzling- processes in the entire universe.

Cosmic rays are extraterrestrial particles-usually protons or heavier ions-that hit the Earth’s atmosphere and create cascades of secondary particles. While cosmic rays approach the earth at a range of energies, scientists long believed that their energy could not exceed 1020 electron volts, some 100 million times the proton energy achievable in Fermilab’s Tevatron, the most powerful particle accelerator in the world. But recent experiments in Japan and Utah have detected a few such ultrahigh energy cosmic rays, raising questions about what extraordinary events in the universe could have produced them.

“How does nature create the conditions to accelerate a tiny particle to such an energy?” asked Alan Watson, physics professor at the University of Leeds, UK, and spokesperson for the Pierre Auger collaboration of 250 scientists from 14 countries. “Tracking these ultrahigh-energy particles back to their sources will answer that question.”

Scientific theory can account for the sources of low- and medium-energy cosmic rays, but the origin of these rare high-energy cosmic rays remains a mystery. To identify the cosmic mechanisms that produce microscopic particles at macroscopic energy, the Pierre Auger collaboration is installing an array that will ultimately comprise 1,600 surface detectors in an area of the Argentine Pampa Amarilla the size of Rhode Island, near the town of Malarg?e, about 600 miles west of Buenos Aires. The first 100 detectors are already surveying the southern sky.

“These highest-energy cosmic rays are messengers from the extreme universe,” said Nobel Prize winner Jim Cronin, of the University of Chicago, who conceived the Auger experiment together with Watson. “They represent a great opportunity for discoveries.”

The highest-energy cosmic rays are extremely rare, hitting the Earth’s atmosphere about once per year per square mile. When complete in 2005, the Pierre Auger observatory will cover approximately 1,200 square miles (3,000 square kilometers), allowing scientists to catch many of these events.

“Our experiment will pick up where the AGASA experiment has left off,” said project manager Paul Mantsch, Fermilab, referring to the Akeno Giant Air Shower Array (AGASA) experiment in Japan. “At highest energies, the astonishing results from the two largest cosmic-ray experiments appear to be in conflict. AGASA sees more events than the HiRes experiment in Utah, but the statistics of both experiments are limited.”

The Pierre Auger project, named after the pioneering French physicist who first observed extended air showers in 1938, combines the detection methods used in the Japanese and Utah experiments. Surface detectors are spaced one mile apart. Each surface unit consists of a 4-foot-high cylindrical tank filled with 3,000 gallons of pure water, a solar panel, and an antenna for wireless transmission of data. Sensors register the invisible particle avalanches, triggered at an altitude of six to twelve miles just microseconds earlier, as they reach the ground. The particle showers strike several tanks almost simultaneously.

In addition to the tanks, the new observatory will feature 24 HiRes-type fluorescence telescopes that can pick up the faint ultraviolet glow emitted by air showers in mid-air. The fluorescence telescopes, which can only be operated during dark, moonless nights, are sensitive enough to pick up the light emitted by a 4-watt lamp traveling six miles away at almost the speed of light.

“It is a really beautiful thing that we have a hybrid system,” said Watson. “We can look at air showers in two modes. We can measure their energy in two independent ways.”

The Pierre Auger collaboration is in the process of preparing a proposal for a second site of its observatory, to be located in the United States. Featuring the same design as the Argentinean site, the second detector array would scan the northern sky for the sources of the most powerful cosmic rays.

Funding for the $55 million Pierre Auger Observatory in Argentina has come from 14 member nations. The U.S. contributes 20 percent of the total cost, with support provided by the Office of Science of the Department of Energy and by the National Science Foundation. A list of all participating institutions is available at http://auger.cnrs.fr/collaboration.html

Fermilab is a national laboratory funded by the Office of Science of the U.S. Department of Energy, operated by Universities Research Association, Inc.

Original Source: Fermilab News Release

Image credit: Caltech

The possibility of a 30-metre telescope moved closer to reality this week when the Gordon and Betty Moore Foundation awarded $17.5 million to fund the detailed design study. Planned for completion in 2012, the Thirty-Metre Telescope will have nine times the light-gathering power of the 10-metre Keck observatory; the largest in the world. With its adaptive optics capacity, it should be able to produce images which are 12 times sharper than the Hubble Space Telescope. The building site hasn?t been chosen yet, but it will probably be in Mexico, Hawaii or Chile.

The dream of a giant optical telescope to improve our understanding of the universe and its origin has moved a step closer to reality today. The Gordon and Betty Moore Foundation awarded $17.5 million to fund a detailed design study of the Thirty-Meter Telescope (TMT). This new grant allows the California Institute of Technology and its partner, the University of California, to proceed with formulating detailed construction plans for the telescope.

An earlier, more modest, study completed in 2002 resulted in a roughed-out concept for a 30-meter-diameter optical and infrared telescope, complete with adaptive optics, which would result in images more than 12 times sharper than those of the Hubble Space Telescope. The TMT– formerly known as the California Extremely Large Telescope–will have nine times the light-gathering ability of one of the 10-meter Keck Telescopes, which are currently the largest in the world.

“Caltech and the University of California will work in close and constant collaboration to achieve the goals of the design effort,” states Richard Ellis, director of optical observatories at Caltech. “We’ve had promising discussions with the Association of Universities for Research in Astronomy and the Association of Canadian Universities for Research in Astronomy, both of whom are considering joining us as major collaborators. Constructing and operating a telescope of this size will be a huge undertaking requiring a large collaborative effort.”

According to Ellis, the Gordon and Betty Moore Foundation’s early funding will provide crucial momentum to carry the project to fruition. “The major goals of the design phase will include an extensive review and optimization of the telescope design, addressing areas of risk, for example by early testing of key components, and staffing a project office in Pasadena.”

With such a telescope, astrophysicists will be able to study the earliest galaxies and the details of their formation as well as to pinpoint the processes which lead to young planetary systems around nearby stars.

“The key new capabilities promised by the Thirty Meter Telescope will include unprecedented angular resolution, necessary to resolve detail in early galaxies and forming planetary systems, and of course the huge collecting area for studying the faintest sources, which are often the most important to understand, but are beyond the reach of current facilities.”” adds Chuck Steidel, professor of astronomy, who chaired a science committee charged with making the case for the proposed facility.

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 a yet undetermined site in Hawaii, Chile, or Mexico. The end of this phase would mark the beginning of regular astronomical observations, perhaps by 2012.

Ellis says TMT is a natural project for Caltech to undertake, given its decades of experience in constructing, operating, and conducting science with the world’s largest telescopes. Before Caltech and the University of California’s jointly-operated Keck Observatory went on-line in the 1990s, Caltech’s 200-inch Hale Telescope at Palomar Observatory was among the largest optical instruments in the world. Today, 54 years after its first light, the Hale Telescope is still in continuous use as a major research instrument.

“This project takes Caltech’s success in ground-based astronomy to the next level of ambition,” Ellis says. “The TMT will also build logically on the successful demonstration of the segmented primary mirrors of the Keck telescopes, a major innovation at the time but now recognized as the only route to making a primary mirror of this size.”

Caltech is currently in the process of hiring a project manager to lead the technical effort for the TMT.

The Gordon and Betty Moore Foundation was created in November 2000 with a multibillion-dollar contribution from its founders. The mission of the Foundation is to seek and develop outcome-based projects that will improve the quality of life for future generations. The majority of the Foundation’s grant making concerns large-scale initiatives in four general program areas: the environment, higher education, science, and San Francisco Bay Area projects.

Original Source: Caltech News Release

Image credit:: Keck

The 10-metre Keck II observatory took an important step forward recently when it began observations with its new adaptive optics system. The system uses a laser to create a fake star about 90 kilometres up in the sky – a computer can then use this to calculate how to remove the effect of atmospheric disturbances. Adaptive optics have been used on smaller telescopes, but this is the first time it’s been employed on a telescope as large as the mighty Keck II; it took nine years to adapt the observatory.

A major milestone in astronomical history took place recently at the W.M. Keck Observatory when scientists, for the first time, used a laser to create an artificial guide star on the Keck II 10-meter telescope to correct the blurring of a star with adaptive optics (AO). Laser guide stars have been used on smaller telescopes, but this is their first successful use on the current generation of the world’s largest telescopes. The resulting image (Figure 1), captured by the NIRC2 infrared camera, was the first demonstration of a laser guide star adaptive optics (LGS AO) system on a large telescope. When complete, the LGS AO system will mark a new era of astronomy in which astronomers will be able to see virtually any object in the sky with the clarity of adaptive optics.

“This is one of the most gratifying moments in all my years at Keck,” remarked Dr. Frederic Chaffee, director of the W.M. Keck Observatory the evening the observations were made. “Like any positive first light result, there is much to be done before the system can be considered operational. But also like any positive first light result, it shows that it can be done, and gives us great optimism that our goals are not impossible dreams, but are instead attainable realities.”

Adaptive optics is a technique that has revolutionized ground-based astronomy through its ability to remove the blurring of starlight caused by the earth?s atmosphere. Its requirement of a relatively bright “guide star” in the same field of view as the scientific object of study has generally limited the use of AO to about one percent of the objects in the sky.

To overcome this restriction, in 1994 the W.M. Keck Observatory began working with Lawrence Livermore National Labs (LLNL) to develop an artificial guide star system. By using a laser to create a ?virtual star,? astronomers can study any object in the vicinity of much fainter (up to 19th magnitude) objects with adaptive optics and reduce its dependence on bright, naturally occurring guide stars. Doing so will increase sky coverage for the Keck adaptive optics system from an estimated one percent of all objects in the sky, to more than 80 percent.

“This new capability of using a laser guide star with a large telescope has invited astronomers to start exploring the night sky in a much more comprehensive manner,” said Adam Contos, optics engineer at the W.M. Keck Observatory. “In the future, I would expect most major observatories to be installing similar systems to take advantage of this incredible enhancement to their AO capabilities.”

In January 2001, after more than seven years in development, the Keck and LLNL teams celebrated the completion of the Keck laser guide star system. The artificial star results when light from a 15-watt dye laser causes a naturally occurring layer of sodium atoms to glow about 90 km (56 miles) above the earth’s surface. It would take another two years of sophisticated research and design before the laser system could be integrated into the Keck II adaptive optics system.

In the early morning hours of September 20th, all subsystems finally came together to reveal the unique capability of the Keck LGS AO system and its potential to resolve extremely faint objects. The system locked on a 15th magnitude star, a member of a well-known T Tauri binary called HK Tau and revealed details of the circumstellar disk of the companion star. It was the first time an adaptive optics system on a very large telescope had ever used an artificial guide star to resolve a faint object.

A key challenge the LGS AO team faced was how successful the efforts would be to integrate and achieve good performance measurements for each required sub-system. Concerns about the power of the laser and its spot quality, operation of the laser traffic control system, the ability of the new sensors to lock on fainter guide stars, and being able to optimize the image quality through an accurate understanding of the aberrations that could not be measured by using the laser guide star, were all factored into the evening’s observing.

“First light was a superb team effort,” said Dr. Peter Wizinowich, team leader for the adaptive optics team at W.M. Keck Observatory. “It was very satisfying to have each of the many subsystems perform so well on our first attempt. To quote Virgil, ‘Audentes Fortuna Juvat,’ fortune favors the bold.”

The quality of the LGS AO first light images was extremely high. While locked on a 14th magnitude star, the Keck LGS AO system recorded “Strehl ratios” of 36 percent (at 2.1 micron wavelength, 30-second exposure time, Figure 3), compared to four percent for uncorrected images. Strehl ratios measure the degree to which an optical system approaches “diffraction-limited” perfection, or the theoretical performance limit, of the telescope.

Another performance metric, the “full width at half maximum” (FWHM), for this 14th magnitude star was 50 milli-arcseconds, compared to 183 milli-arcseconds for the uncorrected image. FWHM measurements help astronomers determine the actual edges of an object, where the detection may be imprecise or difficult to determine. The measurement of 50 milli-arcseconds is about equivalent to being able to distinguish a pair of car headlights in New York while standing in Los Angeles.

Throughout the evening, the laser guide star held steady and bright, shining at an approximate magnitude of 9.5, about 25 times fainter than what the human eye can see, but ideal for the Keck adaptive optics system to measure and correct for atmospheric distortions.

Additional work is underway before the Keck LGS AO system can be considered fully operational. The Keck LGS AO system will be available for limited shared risk science next year, with full deployment to the Keck user community in 2005.

“Even with just this first test, astronomers are already clamoring to use the laser guide star system to study distant galaxies with an unprecedented resolution and power,” said Dr. David Le Mignant, adaptive optics instrument scientist at the W.M. Keck Observatory, California Association for Research in Astronomy. “By next year, adaptive optics will be used to study the rich formation history of early galaxies.”

The importance of this breakthrough to worldwide astronomy was summed up by Dr. Matt Mountain, the director of the Gemini Observatory, which operates twin 8-meter telescopes, one on Mauna Kea and one on Cerro Pachon in Chile: “This is a critical milestone for all ground-based astronomy, not just for our current generation of eight to 10-meter class telescopes, but also for our dreams of 30-meter telescopes.”

Team members responsible for the Keck LGS AO system are Antonin Bouchez, Jason Chin, Adam Contos, Scott Hartman, Erik Johansson, Robert Lafon, David Le Mignant, Chris Neyman, Paul Stomski, Doug Summers, Marcos van Dam, and Peter Wizinowich, all from the W.M. Keck Observatory, California Association for Research in Astronomy. The team gave special thanks to their collaborators at LLNL: Dee Pennington, Curtis Brown and Pam Danforth.

The laser guide star adaptive optics system was funded by the W.M. Keck Foundation.

The W.M. Keck Observatory is operated by the California Association for Research in Astronomy, a scientific partnership of the California Institute of Technology.

Original Source: Keck News Release

Image credit: PPARC

The Canadian Federation for Innovation announced today that it will be contributing $12.3 million CDN for the development of the SCUBA 2 project – an instrument that will be able to detect objects in the sub-millimetre wavelengths (in between radio and infrared). SCUBA 2 will be faster, imaging objects in hours instead of weeks, and it will be much more sensitive, allowing it to look further into space. Sub-millimetre astronomy is a newer field of research, which allows astronomers to penetrate clouds of obscuring dust to look at comets, the birthplace of stars, and distant galaxies.

Astronomers are poised to take another giant leap into some of the coldest regions of space following the announcement that Canada will join the UK in developing a new generation camera for the James Clerk Maxwell Telescope (JCMT) in Hawaii – the world’s largest telescope for studying astronomy at sub-millimetre wavelengths.

The announcement today (26 September 2003) of a grant of ?5.5 million (12.3 million Canadian Dollars) from the Canadian Foundation for Innovation will contribute to the development of a new instrument, SCUBA 2. The UK, through the Particle Physics and Astronomy Research Council (PPARC) will also contribute some ?4 million to the development of the instrument with a further ?2.3 million coming from the JCMT partner Agencies contributions (UK, Canada and the Netherlands).

The project is lead by the UK Astronomy Technology Centre (UK ATC) at the Royal Observatory, Edinburgh. The new instrument will supersede the original groundbreaking Sub-millimetre Common User Bolometer Array (SCUBA) frequently cited as one of the most important ground-based astronomical instruments ever. SCUBA was also designed and constructed at the Royal Observatory, Edinburgh in collaboration with Queen Mary, University of London.

Professor Ian Halliday, Chief Executive of PPARC commented “SCUBA 2 will enable the JCMT to maintain its position as one of the world’s leading facilities in the exotic field of sub-millimetre astronomy. We are delighted that our Canadian colleagues have joined with us to spearhead its development.”

Dr Wayne Holland, SCUBA 2 Project scientist at the UK ATC said “To work in this challenging field requires special techniques and cutting-edge technology. With a much larger field of view and the capability to limit background ‘noise’, SCUBA 2 will map large areas of sky up to 1000 times faster than the current SCUBA camera. Sub-millimetre detectors must be cooled to a fraction of a degree above absolute zero (-273 decrees C). The UK ATC has considerable experience of producing electrical and optical systems that deliver a high level of performance at these extreme temperatures.”

Dr Adrian Russell, Director of the UK ATC said: “SCUBA 2 will be a second revolution in sub-millimetre astronomy and will build on the ground-breaking science that its predecessor SCUBA (1) has already delivered. The JCMT community will have access to a tremendously powerful tool which will not only carry out world class science, but will put them in an enviable position to exploit the new ALMA telescope when it comes online. ”

Sub-millimetre astronomy is a new and rapidly developing field that allows scientists to probe the composition of comets, the birthplaces of stars and the most distant galaxies. Sub-millimetre wavelengths lie between those of traditional radio astronomy and those of the newer but now fairly well understood infrared astronomy. Astronomers detect light at sub-millimetre wavelengths in order to penetrate clouds of cosmic dust.

The vast majority of light from young galaxies in the distant universe is absorbed by dust, and is only observable by astronomers at sub-millimetre wavelengths. The quantity of dust in young galaxies reveals whether stars formed gradually, or mainly in sudden bursts, in the early history of the Universe.

SCUBA 2 will actually have two cameras – each operating simultaneously at a different wavelength in the sub-millimetre band. The 6400 pixels in each camera will cover an 8 x 8 arc-minute patch of sky (about a third of the full moon) or some 16 times the area of the existing SCUBA instrument. The improved sensitivity and imaging power will mean that observations that now take weeks of telescope time with SCUBA will be made in only a few tens of minutes.

Original Source: PPARC News Release

Image credit: NASA

The last of the Great Observatories, NASA’s Space Infrared Telescope Facility, gathered first light from two of its instruments: the infrared array camera and the multi-band imaging photometer. These tests are part of the observatory’s two-month in-orbit checkout, which will be followed by a one-month verification phase. Operators will continue to fine-tune SIRTF’s focus and test out another instrument later this month. Once it’s finally ready for scientific duty, SIRTF will study galaxies and stars in the infrared spectrum and search for signs of planetary disks forming around young stars to help us understand how our own solar system formed.

NASA’s Space Infrared Telescope Facility has switched on two of its onboard instruments and captured some preliminary star-studded images. The space observatory was launched from Cape Canaveral, Fla., on August 25.

The images were taken as part of an operational test of the infrared array camera. It will take about a month to fully focus and fine-tune the telescope and cool it to optimal operating temperature, so these early images will not be as sharp or polished as future pictures.

“We’re extremely pleased, because these first images have exceeded our expectations,” said Dr. Michael Werner, the Space Infrared Telescope Facility project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “We can’t wait to see the images and spectra we’ll get once the telescope is cooled down and instruments are working at full capacity.”

The most striking image is available on the Internet at the following websites:

http://sirtf.caltech.edu/news/releases/ssc2003-03/

The telescope’s dust cover was ejected on Aug. 29, and its aperture door opened on Aug. 30. The spacecraft is operating in normal mode, and all systems are operating nominally. The team is very pleased with the rapid progress of the observatory and all of its onboard systems, said Project Manager David Gallagher of JPL.

In addition to the infrared array camera, the multi-band imaging photometer instrument was also switched on for the first time in a successful engineering test. The spacecraft’s pointing calibration and reference sensor detected light from a star cluster. The third instrument, the infrared spectrograph, will be turned on later this month.

These operations are part of the mission’s two-month in-orbit checkout, which will be followed by a one-month science verification phase. After that, the science mission will begin a quest to study galaxies, stars and other celestial objects, and to look for possible planetary construction zones in dusty discs around other stars.

JPL, a division of the California Institute of Technology in Pasadena, manages the Space Infrared Telescope Facility for NASA’s Office of Space Science, Washington, D.C. More information about the Space Infrared Telescope Facility is available at http://sirtf.caltech.edu/. For more information about NASA on the Internet, visit http://www.nasa.gov.

Source: NASA Press Release

Image credit: PPARC

On August 14, a new detector designed to determine the mass of neutrinos began operations in an old mine in Minnesota, USA. The Main Injector Neutrino Oscillation Search (MINOS) detector is 30-metres long and consists of 486 massive octagonal plates, each of which is 8-metres across. MINOS will initially measure neutrinos coming from Sun, but in August 2004 it will measure man-made neutrinos created in a laboratory more than 700 km away. If the experiment is successful it will help solve the mystery of dark matter, which some astronomers believe comes from the mass of neutrinos.

Today, (August 14th), sees the start of data collection on the Main Injector Neutrino Oscillation Search (MINOS) detector, situated in the Soudan iron mine, Minnesota, USA. UK particle physicists, working within an international collaboration, will use the MINOS detector to investigate the phenomenon of neutrino mass – a puzzle that goes to the heart of our understanding of the Universe.

Neutrinos are pointlike, abundant particles with very little mass. They exist in three types or ‘flavours’ and recent experiments (including those at SNO – the Sudbury Neutrino Observatory) have demonstrated that neutrinos are capable of oscillating between these flavours (electron, tau and muon). This can only happen if one or more of the neutrino flavours does have mass, in contradiction to the Standard Model of particle physics.

The MINOS detector will start measurements of cosmic ray showers penetrating the Earth. It is situated in the Soudan Mine, Minnesota. The 30-metre-long detector consists of 486 massive octagonal planes, lined up like the slices of a loaf of bread. Each plane consists of a sheet of steel about 8 metres high and 2 ? cm thick, covered on one side with a layer of scintillating plastic that emits light when struck by a charged particle.

“MINOS can separate neutrino interactions from their antimatter counterparts – the antineutrinos.” explains UK MINOS spokesperson, Jenny Thomas from University College London. “The data taken now from neutrinos produced in cosmic ray cascades may provide new insight into why the Universe is made of more matter than antimatter. At least, for the first time we will be able to compare the characteristics of neutrinos and anti-neutrinos coming from the atmosphere.”

However, MINOS has more ambitious plans in place for August 2004. Whilst most experiments like SNO measure neutrinos coming from the Sun, when complete, MINOS will instead study a beam of man-made neutrinos, all of the same type or ‘flavour’ – the muon neutrino flavour. This beam will be created at Fermi National Accelerator Laboratory (Fermilab) and sent straight through the Earth to Soudan – a distance of 735 kilometres. No tunnel is needed because neutrinos interact so rarely with matter. A detector is currently being built just outside Fermilab, known as the ‘near’ detector, similar but smaller than the now operational MINOS detector, known as the ‘far’ detector. The ‘near’ detector will act as a control, studying the beam as it leaves Fermilab, then the results will be compared with those from the ‘far’ detector to see if the neutrinos have oscillated into electron or tau neutrinos during their journey.

A million million neutrinos will be created at Fermilab each year, but only 1,500 will interact with the nucleus of an atom in the far detector and generate a signal; the others will pass straight through.

“The realisation that neutrinos oscillate, first demonstrated by the Super Kamiokande experiment in Japan, has been one of the biggest surprises to emerge in particle physics since the inception of the Standard Model more than 30 years ago.” says Jenny Thomas. “The MINOS experiment will measure the oscillation parameters of these neutrinos to an unprecedented accuracy of a few percent; an amazing feat considering neutrinos can usually pass directly through the Earth without interacting at all and that their inferred masses are estimated to be less than 1eV. (The weight ratio of a neutrino to a 1kg bag of sugar is the same as the ratio of a grain of sand to the weight of the earth!). The parameter measurement will open up an entire new field of particle physics, to understand what effect on the universe this tiny neutrino mass has.”

Within two years of turning on the neutrino beam, MINOS should produce an unequivocal measurement of the oscillation of muon neutrinos with none of the uncertainties associated with the atmospheric or solar neutrino source. If indeed the findings are positive, then a new era in particle physics will begin. Theorists will have to incorporate massive neutrinos into the Standard Model, which will have exciting implications. Furthermore cosmologists will have a strong candidate for the ‘missing mass’ of the Universe (which dynamical gravitational measurements show must exist). The experimental side will be just as exciting as we plan new experiments to measure precisely how the different neutrinos change their flavour.

Original Source: PPARC News Release

The Liverpool Telescope, the world’s largest robotic observatory, began operations this week. The 2-metre telescope is operated from Liverpool John Moores University, but it’s actually located in the Canary Islands, and run remotely. The telescope is especially suited to watching astronomical objects which change over time, such as Gamma Ray Bursts, supernovae, asteroids and comets. 5% of its time has been donated to the National Schools’ Observatory program, allowing school children to perform astronomy research.

Image credit: Caltech

The Palomar Observatory has begun a new survey of the sky, and will explore the Universe from our solar system out to distant quasars, 10 billion light-years away. The survey will be done with the refurbished 48-inch Oschin telescope with a newly attached digital CCD camera – the largest ever built with 112 separate detectors. The researchers plan to publish images gathered by the telescope onto the web so that other astronomers can search the data for near-earth asteroids, Kuiper Belt objects, supernovae and other objects.

A major new sky survey has begun at the Palomar Observatory. The Palomar-QUEST survey, a collaborative venture between the California Institute of Technology, Yale University, the Jet Propulsion Laboratory, and Indiana University, will explore the universe from our solar system out to the most distant quasars, more than 10 billion light-years away.

The survey will be done using the newly refurbished 48-inch Oschin Telescope, originally used to produce major photographic sky atlases starting in 1950s. At its new technological heart is a very special, fully digital camera. The camera contains 112 digital imaging detectors, known as charge-coupled devices (CCDs). The largest astronomical camera until now has had 30 CCDs. CCDs are often used for digital imaging ranging from common snapshot cameras to sophisticated scientific instruments. Designed and built by scientists at Yale and Indiana Universities, the QUEST (Quasar Equatorial Survey Team) camera was recently installed on the Oschin Telescope. “We are excited by the new data we are starting to obtain from the Palomar Observatory with the new QUEST camera,” says Charles Baltay, Higgins Professor of Physics and Astronomy at Yale University. Baltay’s dream of building a large electronic camera that could capture the entire field of view of a wide-field telescope is now a reality. The survey will generate astronomical data at an unprecedented rate, about one terabyte per month; a terabyte is a million megabytes, an amount of information approximately equivalent to that contained in two million books. In two years, the survey will generate an amount of information about equal to that in the entire Library of Congress.

A major new feature of the Palomar-QUEST survey will be many repeated observations of the same portions of the sky, enabling researchers to find not only objects that move (like asteroids or comets), but also objects that vary in brightness, such as the supernova explosions, variable stars, quasars, or cosmic gamma-ray bursts–and to do this at an unprecedented scale.

“Previous sky surveys provided essentially digital snapshots of the sky”, says S. George Djorgovski, professor of astronomy at Caltech. “Now we are starting to make digital movies of the universe.” Djorgovski and his team, in collaboration with the Yale group, are also planning to use the survey to discover large numbers of very distant quasars–highly luminous objects believed to be powered by massive black holes in the centers of young galaxies–and to use them to probe the early stages of the universe.

Richard Ellis, Steele Professor of Astronomy and director of the Caltech Optical Observatories, will use QUEST in the search for exploding stars, known as supernovae. He and his team, in conjunction with the group from Yale, will use their observations of these exploding stars in an attempt to confirm or deny the recent finding that our universe is accelerating as it expands.

Shri Kulkarni, MacArthur Professor of Astronomy and Planetary Science at Caltech, studies gamma-ray bursts, the most energetic stellar explosions in the cosmos. They are short lived and unpredictable. When a gamma-ray burst is detected its exact location in the sky is uncertain. The automated Oschin Telescope, armed with the QUEST camera’s wide field of view, is poised and ready to pin down the exact location of these explosions, allowing astronomers to catch and study the fading glows of the gamma-ray bursts as they occur.

Closer to home, Caltech associate professor of planetary astronomy Mike Brown is looking for objects at the edge of our solar system, in the icy swarm known as the Kuiper Belt. Brown is convinced that there big objects out there, possibly as big as the planet Mars. He, in collaboration with astronomer David Rabinowitz of Yale, will use QUEST to look for them.

Steve Pravdo, project manager for the Jet Propulsion Laboratory’s Near-Earth Asteroid Tracking (NEAT) Project, will use QUEST to continue the NEAT search which began in 2001. The QUEST camera will extend the search for asteroids that might one day approach or even collide with our planet.

The Palomar-QUEST survey will undoubtedly enable many other kinds of scientific investigations in the years to come. The intent is to make all of the copious amounts of data publicly available in due time on the Web, as a part of the nascent National Virtual Observatory. Roy Williams, member of the professional staff of Caltech’s Center for Advanced Computing Research, is working on the National Virtual Observatory project, which will greatly increase the scientific impact of the data and ease its use for public and educational outreach as well.

The QUEST team members from Indiana University are Jim Musser, Stu Mufson, Kent Honeycutt, Mark Gebhard, and Brice Adams. Yale University’s team includes Charles Baltay, David Rabinowitz, Jeff Snyder, Nick Morgan, Nan Ellman, William Emmet, and Thomas Hurteau. The members from the California Institute of Technology are S. George Djorgovski, Richard Ellis, Ashish Mahabal, and Roy Williams. The Near-Earth Asteroid Tracking team from the Jet Propulsion Laboratory consists of Raymond Bambery, principal investigator, and coinvestigators Michael Hicks, Kenneth Lawrence, Daniel MacDonald, and Steven Pravdo.

Installation of the QUEST camera at the Palomar Observatory was overseen by Robert Brucato, Robert Thicksten, and Hal Petrie.

Original Source: Caltech News Release

Image credit: SALT

The observatory that will house the largest optical telescope in the Southern hemisphere is nearing completion. The Southern African Large Telescope (SALT) is being built by a consortium of six countries at the southern edge of the Kalahari Desert in Africa. The 11-by-10 metre telescope is 18 months away from being done, but the structure of the observatory is nearly complete. The entire project will cost $18 million and be fully operational in late 2004.

A new observatory that promises to give Wisconsin astronomers unique access to the southern sky is now a prominent feature on a remote South African plateau.

The observatory that will house the largest optical telescope in the Southern Hemisphere, known as the Southern African Large Telescope (SALT), is now nearly complete, according to astronomers at UW-Madison. Although the telescope itself is still 18 months from completion, the mirror segments that will make up the 11-by-10-meter hexagonal primary mirror are starting to come together, says Matthew Bershady a UW-Madison professor of astronomy who is helping to oversee planning and construction of the new observatory.

“We are at a point where we have a structure that is nearly completed,” says Bershady of the observatory situated 220 miles from Cape Town on a mountain plateau at the southern end of the Kalahari Desert. “Now, we are starting to populate the (telescope) truss with glass.”

The $18 million SALT Observatory is being built by a consortium of government and academic institutions from six countries. In addition to UW-Madison, Rutgers and Carnegie Mellon universities, Germany’s University of Gottingen, the University of Canterbury in New Zealand, the United Kingdom Consortium, and the governments of Poland and South Africa are partners in the SALT consortium.

UW-Madison’s contribution is a $3 million imaging spectrograph that is being built under the direction of astronomy Professor Kenneth H. Nordsieck. A spectrograph is a device that breaks light down into its constituent wavelengths, each of which has a different story to tell about the star or galaxy from which the light is gathered.

“We’re past the design stage now,” says Nordsieck of the 500-kilogram instrument that will be at the heart of the new observatory. “We’re cutting metal and polishing glass.”

The Wisconsin spectrograph will be the telescope’s primary scientific instrument. Positioned high above the huge segmented mirror at the prime focus of the telescope, the device will be capable of capturing spectra at a rate of 10 times a second.

To explain the importance of spectroscopy to astronomy, one spectrum – in the words of one astronomer – is worth a thousand pictures.

The device, says Nordsieck, will sample light in the near ultraviolet part of the electromagnetic spectrum: “This is light that our eyes can’t see, but it still gets through the atmosphere. It’s the same kind of light that causes sunburn.”

In addition, the spectrograph will be capable of doing polarimetry, measuring how light waves are scattered as they bounce off objects in space and are pushed and pulled by the immense magnetic fields of interstellar space. Polarimetry, Nordsieck says, helps reveal geometric information, giving astronomers insight into how starlight interacts with the objects it encounters.

“We will also have one of the first large Fabry-Perot devices,” he adds. “It is basically a tunable filter” capable of imaging a large part of the sky.

Fittingly, among the system of lenses to be included in the spectrograph will be a set made of sodium chloride – or salt.

Together, the large, segmented primary mirror and the novel scientific instrumentation will position SALT to break plenty of new ground in the southern skies.

“One of the big things this telescope will be tuned for are the Magellanic Clouds,” says Bershady. “They are important because they are the galaxies nearest to our own, and they offer the best opportunity to study stars and galaxies outside of the Milky Way. It’s always a good thing to look outside of your own immediate environment to find out how unique you are, if at all.”

The SALT construction schedule is right on time, Bershady adds. “That we haven’t slipped at all is amazing,” he says. “Our hope is to stay on track for first light in late 2004.”

Original Source: SALT News Release