Astronomical Observatories

Millimeter Astronomical Observing Techniques II. Science at Millimeter Wavelengths 

Correlator An electronic device that performs the multiplication and averaging of the astronomical signals from aradio telescope. Correlators are used both to process spectral measurements from single antenna telescopes and to process the signals from a collection of electronically connected telescopes. 

Interferometer A collection of electronically connected telescopes used to make high spatial resolution astronomical measurements. 

Isomerism The existence of more than one snbstance having a given molecular composition and mass bnt differing in structure. For example, HNC is an isomer ofHCN. 

Jansky Unit of flux density used in radio astronomy. 1 jansky (Jy) is equal to 10 W m  

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Abstract Detectors play a key role in an astronomical observatory. In astronomy, the role of the telescope and instrument is to bring light to a focus - in effect, the telescope-instrument act as spectacles . The detectors, meanwhile, have the critical role of sensing the light - the detectors are the eyes of an observatory. The performance of an astronomical observatory is directly dependent upon the performance of its detector systems. 

Figure 1. A ground-based astronomical observatory can be depicted as having four major part telescope, adaptive optics (optional), instmment optics, and the detector.

To understand the role of detectors in astronomy, we can divide an astronomical observatory into four major parts as shown in Fig.l. 

Note that there are many other applications of detectors in an astronomical observatory, including detectors that are used for active optics, site monitoring (seeing, cloud cover), surveillance and safety monitoring. 

Department of Astronomy and Space Physics, Uppsala Astronomical Observatory, Box 515, S-751 20 Uppsala, Sweden... 

Astronomical Observatory, were used to carry out the calculations of theoretical equivalent widths of lines, synthetic spectra and a set of plane parallel, line-blanketed, flux constant LTE model atmospheres. The effective temperatures of the stars were determined from photometry, the infrared flux method and corrected, if needed, in order to achieve the LTE excitation balance in the iron abundance results. The gravities were found by forcing Fe I and Fe II to yield the same iron abundances. The microturbulent velocities were determined by forcing Fe I line abundances to be independent of the equivalent width. For more details on the method of analysis and atomic data see Tautvaisiene et al. (2001). 

Astronomical Observatory of Odessa National University, Ukraine... 

National Astronomical Observatory, Mitaka, Tokyo 181-8588, Japan... 

Gilra, D. P., 1972a. Collective excitations and dust particles in space, in The Scientific Results from the Orbiting Astronomical Observatory OAO-2, A. D. Code (Ed.), NASA SP-310, pp. 295-319. 

Tokyo Astronomical Observatory, University of Tokyo Mi taka, Tokyo 181, Japan and... 

Astronomical Observatory and Laboratory for Space Research Beneluxlaan 21, 3527 HS UTRECHT, the Netherlands... 

Tokyo Astronomical Observatory, The University of Tokyo Mitaka, Tokyo, 181 JAPAN... 

Kinki University, Higashi-Osaka, Osaka 577. 2 Tokyo Astronomical Observatory, Mitaka, Tokyo 181 3 Department of Astronomy, University of Tokyo, Tokyo 113... 

South African Astronomical Observatory P.0. Box 9, Observatory 7935, Cape, South Africa... 

Japan Society for the Promotion of Science Tokyo Astronomical Observatory Tokyo Geographical Society Astronomical Society of Japan... 

I.G. Naan, The symmetrical universe, (Translation). Academy of Sciences of the Republic of Estonia. Publication of Tartu Astronomical Observatory, 1964, 34, 6, 13 pages. 

The hydrogen atom burst open the field of radio astronomy. Today, radio astronomical observatories are located at strategic sites in many nations of the world in both hemispheres. Scientists... 

Astronomical Observatory Kyiv National University 3 Observatoma Str. 

Volodymyr Marchenko Astronomical Observatory of Taras Shevchenko... 

Michal Ostrowski Astronomical Observatory Jagiellonian University Ul. Orla 171 30-244 Krakow Poland... 

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