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+ | ====== Overview ====== | ||
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+ | The Caltech Submillimeter Observatory (CSO) is one of the world's premier facilities for astronomical research and instrumentation development. | ||
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+ | With the CSO, astronomers from all over the world observe light naturally emitted by celestial objects at submillimeter wavelengths. | ||
+ | This spectral range, between infrared and radio, is particularly suited to studying the molecular gases and small solid dust particles | ||
+ | that fill the densest regions of the interstellar medium, where stars form as gas clouds contract and collapse under the pull of | ||
+ | gravity. Star formation is best studied in the submillimeter and infrared because interstellar dust absorbs light at shorter wavelengths. | ||
+ | Near the end of their lives, certain stars eject copious amounts of material, forming circumstellar envelopes with a rich assortment | ||
+ | of molecules. Submillimeter observations of galaxies outside the Milky Way trace the history of star formation during the evolution | ||
+ | of the universe. Light from the most distant galaxy observed with the CSO was emitted 12 billion years ago. | ||
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+ | The telescope was designed by Prof. Robert B. Leighton and built at Caltech by Leighton and Prof. Thomas G. Phillips, the founding | ||
+ | CSO director. | ||
+ | The CSO was installed on Maunakea in 1985-7. | ||
+ | Eighty four lightweight hexagonal aluminum honeycomb | ||
+ | panels make up the primary mirror. An active system aligns these panels to maintain the smooth surface needed for submillimeter | ||
+ | observations. Spectrometers and cameras at the CSO use detectors developed at Caltech and other universities. For maximum | ||
+ | sensitivity, these detectors are cooled close to absolute zero temperature. New instruments are deployed as detector technology | ||
+ | advances. Because atmospheric water vapor absorbs submillimeter radiation, the CSO is located high on Maunakea to take advantage | ||
+ | of the very dry conditions. Most observations are made at night when the atmosphere is driest and most stable. As a university facility, | ||
+ | the CSO has a strong educational tradition: over 100 students from 25 institutions have used the CSO for doctoral research projects. | ||
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+ | The [[http://www.caltech.edu|California Institute of Technology]] (Caltech) operates the CSO. The CSO is located on [[http://www.ifa.hawaii.edu/mko/|Maunakea]] through an agreement with the [[http://www.ifa.hawaii.edu|University of Hawai'i]]. The [[http://www.nsf.gov|National Science Foundation]] supported the CSO until 2013 March. Prof. [[http://www.astro.caltech.edu/~golwala/|Sunil Golwala]] is the director of the CSO. | ||
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+ | Further information about the [[..:history:history]] of the CSO. | ||
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+ | ===== Characteristics ===== | ||
+ | |||
+ | | Observing wavelengths: | 2mm — 350 μm | | ||
+ | | Primary mirror diameter: | 10.4 m (34 feet) | | ||
+ | | Surface accuracy: | < 15 μm r.m.s. | | ||
+ | | Pointing accuracy: | 3 arcsec r.m.s. | | ||
+ | | Highest angular resolution: | 8 arcseconds | | ||
+ | | Location: | Maunakea, Hawai'i, | | ||
+ | | | at 4070 m (13360 ft) altitude | | ||
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+ | ===== CSO Scientific Achievements ===== | ||
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+ | * Development of superconducting-tunnel-junction detectors and spiderweb bolometers for radio astronomy, now commonly used on ground- and space-based radio observatories (ALMA, CARMA, Herschel, Planck), as well as the first astronomical demonstrations of an emerging new technology, kinetic inductance detectors. | ||
+ | * Determination of the role of atomic carbon in the interstellar medium. | ||
+ | * Detection of the submillimeter “line forest” using the line-survey technique, as well as of key hydride molecules, which has led to an improved understanding of interstellar chemistry. | ||
+ | * Discovery of a new phase of stellar evolution for red giant stars, which occurs just before they completely lose their envelope of gas during the formation of planetary nebulae. | ||
+ | * Mapping of the molecular gas of the radio galaxy Centaurus A, among others. | ||
+ | * Determination of the volatile composition of comets, including the first ground-based detection of HDO (heavy water) in a comet, leading to an improved understanding of the origin of comets and of terrestrial water | ||
+ | * Discovery of ND3, a rare type of ammonia, with emission about 11 orders of magnitude stronger than initially presumed. | ||
+ | * Discovery of signs of intermittent turbulence in interstellar molecular clouds. | ||
+ | * Use of tools such as the Submillimeter High Angular Resolution Camera (SHARC) to image distant, dusty galaxies that are difficult to observe with optical telescopes. | ||
+ | * Spatially resolved imaging of nearby stellar debris disks, using SHARC, providing evidence for the presence of planets in these systems. | ||
+ | * Spectroscopy of distant and local galaxies using the Z-Spec spectrometer—developed at CSO—which has helped yield a better understanding of the processes of galaxy formation and provides a method for measuring galaxies that are too dusty to be seen with optical instruments. | ||
+ | * Mapping of the pressure in the gaseous component of massive galaxy clusters via its interaction with the cosmic microwave background (the thermal Sunyaev-Zel’dovich effect). | ||
+ | * The first detection of the change in the cosmic microwave background caused by its interaction with the gaseous component of a high-speed subclump within a massive galaxy cluster (the kinetic Sunyaev-Zel’dovich effect). |