Journal articles: 'Instrumentation, Techniques, and Astronomical Observations'

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Sawant, Sailee M., and Daniel Batcheldor. "Charge-injection Device Imaging of Sirius with Contrast Ratios Greater than 1:26 Million." Publications of the Astronomical Society of the Pacific 134, no. 1033 (March 1, 2022): 034503. http://dx.doi.org/10.1088/1538-3873/ac54c2.

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Abstract The intrinsic nature of many astronomical objects, such as binary and multiple systems, exoplanets, circumstellar and debris disks, and quasar host galaxies, introduces challenging requirements for observational instrumentation and techniques. In each case, we encounter situations where the light from bright sources hampers our ability to detect surrounding fainter targets. To explore all features of such astronomical scenes, we must perform observations at the maximum possible contrast ratios. Charge-injection devices (CIDs) are capable of potentially exceeding contrast ratios of log 10 ( CR ) > 9 (i.e., 1 part in 1 billion) due to their unique readout architectures and inherent anti-blooming abilities. An on-sky testing of a commercially available CID, SpectraCAM XDR (SXDR), demonstrated raw contrast ratios from sub-optimal ground-based astronomical observations that imposed practical limits on the maximum achievable contrast ratios using CIDs. Here, we demonstrate the extreme contrast ratio imaging capabilities of the SXDR using observations of Sirius with the 1.0 m Jacobus Kapteyn Telescope, La Palma, Spain. Based on wavelet-based analysis and precise photometric and astrometric calibrations, we report a direct contrast ratio of Δm r = 18.54, log 10 ( CR ) = 7.41 ± 0.08 , or 1 part in 26 million. This is an order of magnitude higher compared to the previous CID results.

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De la Luz, Victor, J. Americo Gonzalez-Esparza, Maria A. Sergeeva, Pedro Corona-Romero, L. Xavier González, Julio C. Mejia-Ambriz, Jose F. Valdés-Galicia, et al. "First joint observations of space weather events over Mexico." Annales Geophysicae 36, no. 5 (October 11, 2018): 1347–60. http://dx.doi.org/10.5194/angeo-36-1347-2018.

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Abstract. The Mexican Space Weather Service (SCiESMEX in Spanish) and National Space Weather Laboratory (LANCE in Spanish) were organized in 2014 and in 2016, respectively, to provide space weather monitoring and alerts, as well as scientific research in Mexico. In this work, we present the results of the first joint observations of two events (22 June and 29 September 2015) with our local network of instruments and their related products. This network includes the MEXART radio telescope (solar flare and radio burst), the Compact Astronomical Low-frequency, Low-cost Instrument for Spectroscopy in Transportable Observatories (CALLISTO) at the MEXART station (solar radio burst), the Mexico City Cosmic Ray Observatory (cosmic ray fluxes), GPS receiver networks (ionospheric disturbances), and the Teoloyucan Geomagnetic Observatory (geomagnetic field). The observations show that we detected significant space weather effects over the Mexican territory: geomagnetic and ionospheric disturbances (22 June 2015), variations in cosmic ray fluxes, and also radio communications' interferences (29 September 2015). The effects of these perturbations were registered, for the first time, using space weather products by SCiESMEX: total electron content (TEC) maps, regional geomagnetic index Kmex, radio spectrographs of low frequency, and cosmic ray fluxes. These results prove the importance of monitoring space weather phenomena in the region and the need to strengthening the instrumentation network. Keywords. Solar physics, astrophysics, and astronomy (instruments and techniques)

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Li, T. P. "Imaging in Hard X-ray Astronomy." Symposium - International Astronomical Union 214 (2003): 70–83. http://dx.doi.org/10.1017/s0074180900194173.

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The energy range of hard X-rays is a key waveband to the study of high energy processes in celestial objects, but still remains poorly explored. In contrast to direct imaging methods used in the low energy X-ray and high energy gamma-ray bands, currently imaging in the hard X-ray band is mainly achieved through various modulation techniques. A new inversion technique, the direct demodulation method, has been developed since early 90s. with this technique, wide field and high resolution images can be derived from scanning data of a simple collimated detector. The feasibility of this technique has been confirmed by experiment, balloon-borne observation and analyzing simulated and real astronomical data. Based the development of methodology and instrumentation, a high energy astrophysics mission – Hard X-ray Modulation Telescope (HXMT) has been proposed and selected in China for a four-year Phase-A study. The main scientific objectives are a full-sky hard X-ray (20–200 keV) imaging survey and high signal-to-noise ratio timing studies of high energy sources.

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Modiri, Sadegh, Robert Heinkelmann, Santiago Belda, Zinovy Malkin, Mostafa Hoseini, Monika Korte, José M. Ferrándiz, and Harald Schuh. "Towards Understanding the Interconnection between Celestial Pole Motion and Earth’s Magnetic Field Using Space Geodetic Techniques." Sensors 21, no. 22 (November 13, 2021): 7555. http://dx.doi.org/10.3390/s21227555.

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The understanding of forced temporal variations in celestial pole motion (CPM) could bring us significantly closer to meeting the accuracy goals pursued by the Global Geodetic Observing System (GGOS) of the International Association of Geodesy (IAG), i.e., 1 mm accuracy and 0.1 mm/year stability on global scales in terms of the Earth orientation parameters. Besides astronomical forcing, CPM excitation depends on the processes in the fluid core and the core–mantle boundary. The same processes are responsible for the variations in the geomagnetic field (GMF). Several investigations were conducted during the last decade to find a possible interconnection of GMF changes with the length of day (LOD) variations. However, less attention was paid to the interdependence of the GMF changes and the CPM variations. This study uses the celestial pole offsets (CPO) time series obtained from very long baseline interferometry (VLBI) observations and data such as spherical harmonic coefficients, geomagnetic jerk, and magnetic field dipole moment from a state-of-the-art geomagnetic field model to explore the correlation between them. In this study, we use wavelet coherence analysis to compute the correspondence between the two non-stationary time series in the time–frequency domain. Our preliminary results reveal interesting common features in the CPM and GMF variations, which show the potential to improve the understanding of the GMF’s contribution to the Earth’s rotation. Special attention is given to the corresponding signal between FCN and GMF and potential time lags between geomagnetic jerks and rotational variations.

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Drew, Patrick M., and Caitlin M. Casey. "No Redshift Evolution of Galaxies’ Dust Temperatures Seen from 0 < z < 2." Astrophysical Journal 930, no. 2 (May 1, 2022): 142. http://dx.doi.org/10.3847/1538-4357/ac6270.

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Abstract Some recent literature has claimed there to be an evolution in galaxies’ dust temperatures toward warmer (or colder) spectral energy distributions (SEDs) between low and high redshift. These conclusions are driven by both theoretical models and empirical measurement. Such claims sometimes contradict one another and are prone to biases in samples or SED fitting techniques. What has made direct comparisons difficult is that there is no uniform approach to fitting galaxies’ infrared/millimeter SEDs. Here we aim to standardize the measurement of galaxies’ dust temperatures with a python-based SED fitting procedure, MCIRSED. 1 1 Publicly available at github.com/pdrew32/mcirsed. We draw on reference data sets observed by Infrared Astronomical Satellite, Herschel, and Scuba-2 to test for redshift evolution out to z ∼ 2. We anchor our work to the L IR–λ peak plane, where there is an empirically observed anticorrelation between IR luminosity and rest-frame peak wavelength (an observational proxy for luminosity-weighted dust temperature) such that λ peak = λ t ( L IR / L t ) η where η = −0.09 ± 0.01, Lt = 1012 L ⊙, and λ t = 92 ± 2 μm. We find no evidence for redshift evolution of galaxies’ temperatures, or λ peak, at fixed L IR from 0 < z < 2 with >99.99% confidence. Our finding does not preclude evolution in dust temperatures at fixed stellar mass, which is expected from a nonevolving L IR–λ peak relation and a strongly evolving SFR–M⋆ relation. The breadth of dust temperatures ( σ log λ peak ) at a given L IR is likely driven by variation in galaxies’ dust geometries and sizes, and it does not evolve. Testing for L IR–λ peak evolution toward higher redshift (z ∼ 5−6) requires better sampling of galaxies’ dust SEDs near their peaks (observed ∼200–600 μm) with ≲1 mJy sensitivity. This poses a significant challenge to current instrumentation.

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Yoshizawa, M. "New Astrometric Instrumentation in Japan." Symposium - International Astronomical Union 166 (1995): 31–34. http://dx.doi.org/10.1017/s0074180900227794.

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The meridian circle is one of the most fundamental instrument in the field of astrometry where the astronomical objects are studied observationally for positions and their changes on the celestial sphere. At the Tokyo Astronomical Observatory (= National Astronomical Observatory since July, 1988) the Gautier Meridian Circle of 1903 was used until 1982 for various international meridian circle observations like SRS and NPZT programs, as well as for observations of OB stars, and the Moon and planets.

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Davydov, V. Yu. "Compensation of refraction in astronomical interference observations." Measurement Techniques 36, no. 6 (June 1993): 662–67. http://dx.doi.org/10.1007/bf00980011.

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Branham, Richard L. "Techniques for dealing with discordant observations." Symposium - International Astronomical Union 114 (1986): 229–31. http://dx.doi.org/10.1017/s0074180900148247.

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To test any theory such as theories of motion–Newtonian or relativistic–of solar system objects, one must compare the predictions of theory with observation. But discordant observations habitually plague the reducer of astronomical data. To alleviate the baleful effects, particularly harmful when the observations are reduced by the method of least squares, of discordant data investigators almost invariably reject observations whose corresponding (0-C)'s or post-solution residuals exceed a cutoff. But techniques that are insensitive to the assumption that the observational errors are normally distributed, called robust estimation in the literature, have also been developed.

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Guélin, Michel. "Radio and Millimetre Observations of Less Complex Molecules." Symposium - International Astronomical Union 120 (1987): 171–81. http://dx.doi.org/10.1017/s0074180900153987.

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Progress in laboratory and astronomical instrumentation has renewed the already large interest for simple astrophysical molecules. On the laboratory side, one of the most notable advances has been the spectroscopic observation of an increasing number of small reactive molecular species. On the astronomical side, the access to submillimetre wavelengths and the completion of millimetric interferometers and large single-dish telescopes, have allowed the detection of many new molecular species and open the way for detailed studies of the distribution of molecules in interstellar and circumstellar clouds.

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Edberg, Stephen J. "Working with Amateur Astronomers." International Astronomical Union Colloquium 98 (1988): 95–99. http://dx.doi.org/10.1017/s0252921100092307.

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Amateur astronomers have a vast store of talent and expertise in making astronomical observations. When carefully channelled, their enthusiasm coupled with these characteristics can lead to the acquisition of large volumes of high-quality astronomical data. The Amateur Observation Network of the International Halley Watch (IHW) was organized to encourage comet observations by amateurs, standardize techniques whenever possible, and then collect and archive these observations for use by the astronomical community in the near and distant future as part of the whole IHW archive. The lessons learned from this experience will be useful to organizers who plan observation campaigns involving amateur astronomers in the future.

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Vondrák, Jan, Cyril Ron, and Ivan Pešek. "Survey of Observational Techniques and Hipparcos Reanalysis." International Astronomical Union Colloquium 178 (2000): 237–50. http://dx.doi.org/10.1017/s0252921100061376.

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AbstractPolar motion and Universal Time have been regularly determined since 1899 and 1956, respectively, at a number of observatories all over the world. Before the International Earth Rotation Service (IERS) was established in 1988, the classical astrometry instruments such as visual zenith-telescopes, PZTs, transit instruments, astrolabes etc. were used. The survey of all these instruments and the methods of observation used is described. The values of instantaneous latitude and UT0-UTC made at a set of selected observatories and based on individual star observations have been collected at the Astronomical Institute in Prague during the past years. They were recalculated using the most recent astronomical standards and the Hipparcos Catalogue, and used to determine the Earth orientation parameters (polar motion, celestial pole offsets and Universal Time). The most recent solution, based on about 4.5 million observations with 47 different instruments at 33 observatories, is described and the results of polar motion presented.

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Klioner, S. A. "Relativistic astrometry and astrometric relativity." Proceedings of the International Astronomical Union 3, S248 (October 2007): 356–62. http://dx.doi.org/10.1017/s174392130801956x.

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AbstractThe interplay between modern astrometry and gravitational physics is very important for the progress in both these fields. Below some threshold of accuracy, Newtonian physics fails to describe observational data and the Einstein's relativity theory must be used to model the data adequately. Many high-accuracy astronomical techniques have already passed this threshold. Moreover, modern astronomical observations cannot be adequately modeled if relativistic effects are considered as small corrections to Newtonian models. The whole way of thinking must be made compatible with relativity: this starts with the concepts of time, space and reference systems.An overview of the standard general-relativistic framework for modeling of high-accuracy astronomical observations is given. Using this framework one can construct a standard set of building blocks for relativistic models. A suitable combination of these building blocks can be used to formulate a model for any given type of astronomical observations. As an example the problem of four dimensional solar system ephemerides is exposed in more detail. The limits of the present relativistic formulation are also briefly summarized.On the other hand, high-accuracy astronomical observations play important role for gravitational physics itself, providing the latter with crucial observational tests. Perspectives for these astronomical tests for the next 15 years are summarized.

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Wood, P. R. "Speckle Observations with a Photon Counting Detector." Publications of the Astronomical Society of Australia 6, no. 2 (1985): 120–26. http://dx.doi.org/10.1017/s1323358000017902.

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AbstractA description of the production of astronomical speckles is given in terms of elementary physical principles. Using simple probability arguments, estimâtes are made of signal-to-noise requirements and magnitude limits for détection; data réduction techniques are discussed. A speckle System used on the AAT (Anglo-Australian Télescope) with the IPCS as detector is described.

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Jankov, S. "Astronomical optical interferometry, I: Methods and instrumentation." Serbian Astronomical Journal, no. 181 (2010): 1–17. http://dx.doi.org/10.2298/saj1081001j.

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Previous decade has seen an achievement of large interferometric projects including 8-10m telescopes and 100m class baselines. Modern computer and control technology has enabled the interferometric combination of light from separate telescopes also in the visible and infrared regimes. Imaging with milli-arcsecond (mas) resolution and astrometry with micro-arcsecond (?as) precision have thus become reality. Here, I review the methods and instrumentation corresponding to the current state in the field of astronomical optical interferometry. First, this review summarizes the development from the pioneering works of Fizeau and Michelson. Next, the fundamental observables are described, followed by the discussion of the basic design principles of modern interferometers. The basic interferometric techniques such as speckle and aperture masking interferometry, aperture synthesis and nulling interferometry are discussed as well. Using the experience of past and existing facilities to illustrate important points, I consider particularly the new generation of large interferometers that has been recently commissioned (most notably, the CHARA, Keck, VLT and LBT Interferometers). Finally, I discuss the longer-term future of optical interferometry, including the possibilities of new large-scale ground-based projects and prospects for space interferometry.

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Šišulák, Stanislav, and Ladislav Pastorek. "Instrumentation and observations at the astronomical observatory in Hurbanovo in 1871–1918." Journal for the History of Astronomy 53, no. 4 (October 18, 2022): 475–96. http://dx.doi.org/10.1177/00218286221127966.

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The period of the last third of 19th century was beneficial to a boom of observatories run by amateur astronomers. One of them was built in Hurbanovo. It is well known that place names have changed throughout history; sometimes more than one was used at the same time, and it often depended on the language in which the historical documents were written. These peculiarities can easily confuse the modern reader. For the sake of clarity, we have decided to use modern official geographical names. Even in Anglophone historiographical literature, modern names are usually used in the first place instead of historical ones. All other historical forms of place names are mentioned in parentheses when they first appear (first in Hungarian, then in German). Several names or variations of those names may be discovered in historical records pertaining to Hurbanovo, e.g.: Stará Ďala (in Slovak), Ó-Gyalla, O Gyalla, Ógyalla, Ogyalla, Ó Gyalla, Ó Gyala, Ó-Gyala, Ó Gyála (in Hungarian), Altdala (in German). The town was named Hurbanovo in 1948. (Slovakia) in 1871 by a local nobleman Nicolaus de Konkoly. The paper is divided into two main parts. The first part is focused on the development of instrumentation and domes of the observatory. The second one is focused on various kinds of astronomical and astrophysical observations performed by the observatory staff from the beginning of the observatory until the dissolution of the Austro-Hungarian Empire in 1918.

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Caldwell, J. "6. Space Observations of Solar System Objects." Transactions of the International Astronomical Union 19, no. 1 (1985): 642–43. http://dx.doi.org/10.1017/s0251107x00006696.

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Solar system objects may be studied in space by two general techniques. Everyone is familiar with the exciting aspects of deep space probes: very high spatial resolution; in situ measurements of particles and fields; in situ chemistry studies by mass spectrographs and gas chromatographs; unique phase angle and occultation opportunities. However, the Solar system can also be studied to great advantage by observatories in orbit around the Earth. The broader spectral range available above the terrestrial atmosphere is as important for planetary studies as it is for investigations of more distant astronomical targets. Both techniques will be discussed in this brief report.

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Klioner, Sergei A., Gérard Petit, Victor A. Brumberg, Nicole Capitaine, Agnès Fienga, Toshio Fukushima, Bernard R. Guinot, et al. "COMMISSION 52: RELATIVITY IN FUNDAMENTAL ASTRONOMY." Proceedings of the International Astronomical Union 4, T27A (December 2008): 55–59. http://dx.doi.org/10.1017/s1743921308025295.

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The tremendous progress in technology which we have witnessed during the last 30 years has led to enormous improvements of observational accuracy in all disciplines of fundamental astronomy. Relativity has been becoming increasingly important for modeling and interpretation of high accuracy astronomical observations during at least these 30 years. It is clear that for current accuracy requirements astronomical problems have to be formulated within the framework of General Relativity Theory. Many high-precision astronomical techniques have already required the application of relativistic effects, which are several orders of magnitude larger than the technical accuracy of observations. In order to interpret the results of such observations, one has to construct involved relativistic models. Many current and planned observational projects can not achieve their goals if relativity is not taken into account properly. The future projects will require the introduction of higher-order relativistic effects. To make the relativistic models consistent with each other for different observational techniques, to formulate them in the simplest possible way for a given accuracy, and to formulate them in a language understandable for astronomers and engineers who have little knowledge of relativity are the challenges of a multidisciplinary research field called Applied Relativity.

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Bogod, V. M., P. M. Svidskiy, E. A. Kurochkin, A. V. Shendrik, and N. P. Everstov. "A Method of Forecasting Solar Activity Based on Radio Astronomical Observations." Astrophysical Bulletin 73, no. 4 (October 2018): 478–86. http://dx.doi.org/10.1134/s1990341318040119.

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Livingston, W. C., C. M. Humphries, J. C. Bhattacharyya, J. Davis, J. L. Heudier, I. M. Kopylov, G. Lelievre, et al. "9. Instruments and Techniques." Transactions of the International Astronomical Union 19, no. 1 (1985): 41–56. http://dx.doi.org/10.1017/s0251107x0000609x.

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Between the Patras and New Delhi General Assemblies no meetings were directly sponsored by Commission 9 because the discipline was amply covered by the following: - “Eighth Symposium on Photoelectronic Image Devices,” Imperial College (London) 5-7 September 1983 (B. L. Morgan, Ed., Academic Press, London, 1984).- “Advanced Technology Optical Telescopes II” Imperial College, 5-7 September 1983.- “Instrumentation in Astronomy V” 7-9 September 1983 (A. Boksenberg and D. Crawford, Eds., Proc. SPIE 415).- IAU Symposium No. 109: “Astrometric Techniques,” 9-12 January 1984, Gainsville (Florida).- “Astronomical Photography 1984,” Edinburgh, 4-6 April 1984 (E. Sim and K. Ishida, Eds., Number 14 of Occasional Reports of the Royal Observatory, Edinburgh).- “IAU Colloquium No. 79: “Very Large Telescopes, Their Instrumentation and Programs,” Garching bei München, 9-12 April 1984 (M. H. Ulrich and K. Kjär, Eds.)

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Tan, Jiatong. "The progress of mini black holes: principles and analytical astronomical observation techniques." Journal of Physics: Conference Series 2083, no. 2 (November 1, 2021): 022040. http://dx.doi.org/10.1088/1742-6596/2083/2/022040.

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Abstract Mini-black hole (MBH) is a concept first proposed by Stephen Hawking in the 1970s. Normally, exploring MBHs will enhance the understanding of quantum theory and gravity theory as well as be helpful in predicting the configuration of the early universe. Based on information retrieval, this paper summarizes the progress of MBHs and takes three major aspects: background, models, practical methods for observations, and analysis. Specifically, the descriptive equations are derived, and different models are discussed separately. These results shed light on the prospective development of quantum field theorem, general relativity, and string theory.

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Cannon, Russell. "Instrumentation Plans at the AAO: 2dF and Beyond." Publications of the Astronomical Society of Australia 12, no. 2 (August 1995): 258–64. http://dx.doi.org/10.1017/s132335800002035x.

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AbstractThis paper is based on a report given at the ASA Conference in July 1994, but takes account of subsequent developments up to the end of the year. The present state of the Two-degree Field (2dF) project for the AAT is reported. Good progress is being made on all fronts but some slippage has occurred, so that the instrument is now expected to begin astronomical observations only during the second half of 1995. An outline of other current and future instrumentation plans at the AAO is given.

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Skirmante, K., N. Jekabsons, K. Salmins, V. Bezrukovs, and M. Nechaeva. "The Joint SLR (Optical Range) and Radar-VLBI Satellite Observations using VIRAC Radio Telescope RT32, RT16 and SLR Station Riga." Latvian Journal of Physics and Technical Sciences 57, no. 1-2 (April 1, 2020): 62–70. http://dx.doi.org/10.2478/lpts-2020-0008.

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AbstractJoint VLBI and SLR satellite tracking is a novel tracking approach to explore potential applications and to work out common procedures to coordinate observations between astronomical observatories in Latvia. Global Navigation Satellite System (GNSS) satellites equipped with laser retroreflectors have been chosen as test targets because they are accessible by both measuring techniques – satellite laser ranging (SLR) and Very Long Base Interferometry (VLBI).The first Joint SLR and VLBI observations of selected GNSS satellites using three of Latvian large-scale astronomical utilities – VIRAC radio telescopes RT32 and RT16 (Ventspils International Radio Astronomy Centre of Ventspils University of Applied Sciences) with L band receivers and SLR station Riga (Institute of Astronomy of University of Latvia) were obtained in 2016 (NKA16) and 2017 (NKA41 and NKA42).

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SKIMANTE, K., Ieglitid EGLITIS, N. JEKABSONS, V. BEZRUKOVS, M. BLEIDERS, M. NECHAEVA, and G. JASMONTS. "Observations of astronomical objects using radio (Irbene RT-32 telescope) and optical (Baldone Schmidt) methods." Astronomical and Astrophysical Transactions, Vol. 32, No. 1, Volume 32, Numéro 1 (September 1, 2020): 13–22. http://dx.doi.org/10.17184/eac.4392.

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Institute of Astronomy (University of Latvia) with Ventspils International Radio Astronomy Centre (Ventspils University of Applied Sciences) participation is implementing the scientific project "Complex investigations of the small bodies in the Solar system" which is related to the research of the small bodies in the Solar system (mainly focusing on asteroids and comets) using methods of radio and optical astronomy and signal processing.To detect the rotation period and other physical characteristics of NEO objects using optical methods, 566 positions and photo-metric observations of NEO objects 2006 VB14 = Y5705 = 345705 (hereafter 2006 VB14) and 1986 DA = 6178 (hereafter 1986 DA) were obtained with Baldone Schmidt telescope in 2018. A Fourier transform was applied to determine the rotation period for asteroid 1986 DA. Value 3.12 0.02 h was obtained. Observations confirm the previously obtained rotation period P = 3.25 h for 2006 VB14. To detect weak (~0.1 Jy) OH maser of astronomical objects using radio methods, a researcher group in VIRAC adapted Irbene RT-32 radio telescope working at 1665.402 and 1667.359 MHz frequencies. Novel data processing methods were used to acquire weak signals. Spectral analysis using Fourier transform and continuous wavelet transform were applied to radio astronomical data from multiple observations related to weak OH maser detection. Successful observations of multiple galactic masers were carried out in 2019 and adapted Irbene RT32 radio telescope is ready for the observations of comets in the near future.

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Elmhamdi, Abouazza, A. S. Kordi, H. A. Al-Trabulsy, M. El-Nawawy, A. A. Ibrahim, N. Ben Nessib, M. A. Abdel-Sabour, and Z. A. Al-Mostafa. "Observations and analysis of NOAA AR 11429 at KSU-Astronomical Observatory." New Astronomy 23-24 (October 2013): 73–81. http://dx.doi.org/10.1016/j.newast.2013.03.007.

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Kleshchonok, V. V., V. L. Karbovsky, M. I. Buromsky, M. V. Lashko, Yu M. Gorbanev, V. I. Kashuba, C. R. Kimakovskiy, et al. "Star occultation by small bodies of the Solar system: current state of observations in Ukraine." Kosmìčna nauka ì tehnologìâ 28, no. 5 (October 28, 2022): 56–66. http://dx.doi.org/10.15407/knit2022.05.056.

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Observations of stars’ occultations by small bodies of the Solar system allow solving of a series of problems described in this article. The Main Astronomical Observatory of the National Academy of Sciences of Ukraine, together with the Astronomical Observatory of the Taras Shevchenko National University of Kyiv, created a software and hardware complex for observing the star coatings with long-focus telescopes. The complex uses a highly sensitive Apogee Alta U47 CCD camera in time delay integration (TDI) mode. It also includes a focus reducer with a block of light filters. The stationary variant of the complex can be used on the AZT-2 telescope of MAO NAS of Ukraine and the AZT-14 of the Lesniki observation station. The mobile complex is also made on the basis of the telescope of Newton’s system (D = 203 mm, F = 1200 mm) and the computerized installation of Sky-Watcher EQ-5 with the GOTO system for field observations. The worth of occultation observations increases significantly when using several observation points. To this end, we have initiated the gathering of the group of observers and their instrumentation from Ukrainian astronomical institutions, both professional and amateur. The Odesa Astronomical Observatory is presented in the group by the Richie-Chrétien telescope OMT-800 (D = 800 mm, F = 2134 mm) with the CCD camera QHY174M GPS at the Mayaki station and Schmidt system telescope (D = 271.25 mm, F = 440 mm) with the “VIDEO SCAN-415-2001” camera at the Kryzhanivka station. The group also includes several amateur observatories. Among them, there are stations in the village of Petrovka in the Odesa region, the astronomical observatory of Lozova school in the Ternopil region, private astronomical observatory L33 at Ananiiv, the Odesa region, and private observatory L58 “Heavenly Owl” in the town of Velikodolinskoye, the Odesa region. A description of the equipment used in these observation points and several examples of effective observations of occultations obtained by this group are given.

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Massari, D., A. Marasco, O. Beltramo-Martin, J. Milli, G. Fiorentino, E. Tolstoy, and F. Kerber. "Successful application of PSF-R techniques to the case of the globular cluster NGC 6121 (M 4)." Astronomy & Astrophysics 634 (January 31, 2020): L5. http://dx.doi.org/10.1051/0004-6361/201937359.

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Context. Precise photometric and astrometric measurements on astronomical images require an accurate knowledge of the point spread function (PSF). When the PSF cannot be modelled directly from the image, PSF-reconstruction techniques become the only viable solution. So far, however, their performance on real observations has rarely been quantified. Aims. In this Letter, we test the performance of a novel hybrid technique, called PRIME, on Adaptive Optics-assisted SPHERE/ZIMPOL observations of the Galactic globular cluster NGC 6121. Methods. PRIME couples PSF-reconstruction techniques, based on control-loop data and direct image fitting performed on the only bright point-like source available in the field of view of the ZIMPOL exposures, with the aim of building the PSF model. Results. By exploiting this model, the magnitudes and positions of the stars in the field can be measured with an unprecedented precision, which surpasses that obtained by more standard methods by at least a factor of four for on-axis stars and by up to a factor of two on fainter, off-axis stars. Conclusions. Our results demonstrate the power of PRIME in recovering precise magnitudes and positions when the information directly coming from astronomical images is limited to only a few point-like sources and, thus, paving the way for a proper analysis of future Extremely Large Telescope observations of sparse stellar fields or individual extragalactic objects.

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Cottrell, P. L. "New Zealand Astronomy in the 1990s." Publications of the Astronomical Society of Australia 9, no. 1 (1991): 64–68. http://dx.doi.org/10.1017/s1323358000024917.

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AbstractThere has been a dramatic increase in astronomical research output in New Zealand over the last decade. This is set to increase with the advent of a number of new pieces of astronomical hardware over the last five years. These include the 1m telescope and associated instrumentation at Mount John and the JANZOS collaboration, with its instrumentation on Black Birch. Black Birch is also the site of the US Naval Observatory’s southern hemisphere astrometric station, where, using a transit circle instrument, they are collecting data which will form part of the International Reference Star Catalogue. As well as these ‘professional’ programs there is also a large network of amateur astronomers, who can provide extremely useful input into certain astronomical programs at the various observatories around the country and the world.A brief overview of the existing New Zealand astronomical scene will be followed by discussion of a number of new initiatives being proposed, which includes an automatic patrol telescope being developed by Carter Observatory, an expansion of the JANZOS collaboration and initial discussion about the possibility of an eastern arm for the Australia Telescope some where in New Zealand. In addition, for programs which require a long timebase of observations, extreme southerly latitudes or longitudinal coverage, New Zealand could provide a unique opportunity.

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Swings, Jean-Pierre. "Examples of Possible Astronomical Research from the Moon." Highlights of Astronomy 11, no. 2 (1998): 984. http://dx.doi.org/10.1017/s1539299600019365.

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As stressed at the second International Lunar Exploration Working Group meeting (Kyoto, October 1996), the Moon, if kept free from pollution, contains a series of remarkable astronomical sites. In particular the following fields of instrumentation and research emerge :(1) very low frequency radio-astronomical arrays to be located on the lunar far side for surveying an entirely new spectrum, albeit at fairly low angular resolution;(2) interferometers in several wavebands to search for extrasolar planets as well as to perform other observations (morphological studies e.g.);(3) transit optical telescopes for the detailed observation of dark matter and other targets;(4) millimeter-wave telescopes for high sensitivity cosmic background mapping;(5) infrared telescopes in permanently cryogenic environment (e.g. the lunar South pole);(6) gravitational wave detectors;(7) cosmic-ray and high energy detectors;

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Schmälzlin, Elmar, Benito Moralejo, Daniel Bodenmüller, Maxim E. Darvin, Gisela Thiede, and Martin M. Roth. "Ultrafast imaging Raman spectroscopy of large-area samples without stepwise scanning." Journal of Sensors and Sensor Systems 5, no. 2 (July 13, 2016): 261–71. http://dx.doi.org/10.5194/jsss-5-261-2016.

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Abstract. Step-by-step, time-consuming scanning of the sample is still the state-of-the-art in imaging Raman spectroscopy. Even for a few 100 image points the measurement time may add up to minutes or hours. A radical decrease in measurement time can be achieved by applying multiplex spectrographs coupled to imaging fiber bundles that are successfully used in astronomy. For optimal use of the scarce and expensive observation time at astronomical observatories, special high-performance spectrograph systems were developed. They are designed for recording thousands of spatially resolved spectra of a two-dimensional image field within one single exposure. Transferring this technology to imaging Raman spectroscopy allows a considerably faster acquisition of chemical maps. Currently, an imaging field of up to 1 cm2 can be investigated. For porcine skin the required measurement time is less than 1 min. For this reason, this technique is of particular interest for medical diagnostics, e.g., the identification of potentially cancerous abnormalities of skin tissue.

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Kulesa, Craig A., Michael C. B. Ashley, Yael Augarten, Colin S. Bonner, Michael G. Burton, Luke Bycroft, Jon Lawrence, et al. "Opportunities for Terahertz Facilities on the High Plateau." Proceedings of the International Astronomical Union 8, S288 (August 2012): 256–63. http://dx.doi.org/10.1017/s1743921312016973.

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AbstractWhile the summit of the Antarctic Plateau has long been expected to harbor the best ground-based sites for terahertz (THz) frequency astronomical investigations, it is only recently that direct observations of exceptional THz atmospheric transmission and stability have been obtained. These observations, in combination with recent technological advancements in astronomical instrumentation and autonomous field platforms, make the recognition and realization of terahertz observatories on the high plateau feasible and timely. Here, we will explore the context of terahertz astronomy in the era of Herschel, and the crucial role that observatories on the Antarctic Plateau can play. We explore the important scientific questions to which observations from this unique environment may be most productively applied. We examine the importance and complementarity of Antarctic THz astronomy in the light of contemporary facilities such as ALMA, CCAT, SOFIA and (U)LDB ballooning. Finally, building from the roots of THz facilities in Antarctica to present efforts, we broadly highlight future facilities that will exploit the unique advantages of the Polar Plateau and provide a meaningful, lasting astrophysical legacy.

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Wang, Jingxiu. "Astronomy Research in China." Transactions of the International Astronomical Union 24, no. 3 (2001): 210–20. http://dx.doi.org/10.1017/s0251107x00000778.

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AbstractDecades of efforts made by Chinese astronomers have established some basic facilities for astronomy observations, such as the 2.16-m optical telescope, the solar magnetic-field telescope, the 13.7-m millimeter-wave radio telescope etc. One mega-science project, the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST), intended for astronomical and astrophysical studies requiring wide fields and large samples, has been initiated and funded.To concentrate the efforts on mega-science projects, to operate and open the national astronomical facilities in a more effective way, and to foster the best astronomers and research groups, the National Astronomical Observatories (NAOs) has been coordinated and organizated. Four research centers, jointly sponsored by observatories of the Chinese Academy of Sciences and universities, have been established. Nine principal research fields have received enhanced support at NAOs. They are: large-scale structure of universe, formation and evolution of galaxies, high-energy and cataclysmic processes in astrophysics, star formation and evolution, solar magnetic activity and heliogeospace environment, astrogeodynamics, dynamics of celestial bodies in the solar system and artificial bodies, space-astronomy technology, and new astronomical techniques and methods.

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Spoelstra, T. A. Th. "Reduction of Interference in Observations with the Westerbork Synthesis Radio Telescope." International Astronomical Union Colloquium 112 (1991): 249–57. http://dx.doi.org/10.1017/s0252921100004073.

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ABSTRACTRadio astronomical observations are increasingly affected by man-made interference of various kinds. Sophisticated software tools have to be developed to cope with interference effects in the data. A calibration procedure is described in which the effects of different categories of errors are separated. If this separation can be performed for interference effects.Interference effects remaining in the data are erroneously interpreted as source structure by self-calibration techniques. This is due to the fact that self-calibration alone does not properly take into account this separation. Some results for the Westerbork Synthesis Radio Telescope are given.

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Khare, Bishun N., Carl Sagan, W. Reid Thompson, Edward T. Arakawa, Caroline Meisse, and Page S. Tuminello. "Optical properties of poly-HCN and their astronomical applications." Canadian Journal of Chemistry 72, no. 3 (March 1, 1994): 678–94. http://dx.doi.org/10.1139/v94-093.

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Matthews (1992) has proposed that HCN "polymer" is ubiquitous in the solar system. We apply vacuum deposition and spectroscopic techniques previously used on synthetic organic heteropolymers (tholins), kerogens, and meteoritic organic residues to the measurement of the optical constants of poly-HCN in the wavelength range 0.05–40 µm. These measurements allow quantitative comparison with spectrophotometry of organic-rich bodies in the outer solar system. In a specific test of Matthews' hypothesis, poly-HCN fails to match the optical constants of the haze of the Saturnian moon, Titan, in the visible and near-infrared, derived from astronomical observations and standard models of the Titan atmosphere. In contrast, a tholin produced from a simulated Titan atmosphere matches within the probable errors. Poly-HCN is much more N-rich than Titan tholin.

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Łukasik, Szymon, André Moitinho, Piotr A. Kowalski, António Falcão, Rita A. Ribeiro, and Piotr Kulczycki. "Survey of Object-Based Data Reduction Techniques in Observational Astronomy." Open Physics 14, no. 1 (January 1, 2016): 579–87. http://dx.doi.org/10.1515/phys-2016-0064.

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AbstractDealing with astronomical observations represents one of the most challenging areas of big data analytics. Besides huge variety of data types, dynamics related to continuous data flow from multiple sources, handling enormous volumes of data is essential. This paper provides an overview of methods aimed at reducing both the number of features/attributes as well as data instances. It concentrates on data mining approaches not related to instruments and observation tools instead working on processed object-based data. The main goal of this article is to describe existing datasets on which algorithms are frequently tested, to characterize and classify available data reduction algorithms and identify promising solutions capable of addressing present and future challenges in astronomy.

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Zhang, Shuimei, Yujie Gu, and Yimin D. Zhang. "Robust Astronomical Imaging in the Presence of Radio Frequency Interference." Journal of Astronomical Instrumentation 08, no. 01 (March 2019): 1940012. http://dx.doi.org/10.1142/s2251171719400129.

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Radio astronomical observations are increasingly contaminated by radio frequency interference (RFI), rendering the development of effective RFI suppression techniques a pressing task. In practice, the existence of model mismatch makes the observing environment more challenging. In this paper, we develop a robust astronomical imaging method in the presence of RFI and model mismatch. The key contribution of the proposed method is the accurate estimation of the actual signal steering vector by maximizing the beamformer output power subject to a constraint that prevents the estimated steering vector from converging to the interference steering vectors. The proposed method is formulated as a quadratically constrained quadratic programming problem that can be solved using efficient numerical approaches. Simulation results demonstrate the effectiveness of the proposed method.

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Kubáček, D., A. Galád, and A. Pravda. "Some comments about observations and image processing of comet 29P/Schwassmann-Wachmann 1." International Astronomical Union Colloquium 173 (1999): 243–48. http://dx.doi.org/10.1017/s0252921100031493.

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AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.

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Hainaut, Olivier R., and Andrew P. Williams. "Impact of satellite constellations on astronomical observations with ESO telescopes in the visible and infrared domains." Astronomy & Astrophysics 636 (April 2020): A121. http://dx.doi.org/10.1051/0004-6361/202037501.

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The effect of satellite mega-constellations on astronomical observations in the visible, near-infrared, and thermal infrared domains is estimated using a simple methodology, which is applied to ESO telescopes and instruments as examples (radio and (sub-)millimetre domains are not considered here). The study considers a total of 18 constellations in development by SpaceX, Amazon, OneWeb, and others, with over 26 thousand satellites, constituting a representative distribution. This study uses a series of simplifications and assumptions in order to obtain conservative, order-of-magnitude estimates of the effects: the satellites are assumed to be uniformly spread over the Earth’s globe, and their magnitude is estimated using a simplistic model calibrated on actual observations. The effect on various types of ground-based telescopic observations is estimated using a geometric probabilistic approach. The “trains” of very-low altitude satellites typically observed immediately after launch are extremely bright due to their very low orbit. They also fall very quickly in the shadow of the Earth after sunset. However, this initial bright state is not considered further, as the satellites quickly disperse into their higher altitude orbits. The number of illuminated satellites from the constellations above the horizon of an observatory ranges from approximately 1600 immediately after sunset, decreasing to 1100 at the end of astronomical twilight, most of them (∼85%) close to the horizon (below 30° of elevation). The large majority of these satellites will be too faint to be seen with the naked eye: at astronomical twilight, 260 would be brighter than magnitude 6 (i.e. visible in exceptional conditions), 110 brighter than 5 (i.e. visible in good conditions). Again, most of them (∼95%) will be close to the horizon (below 30° of elevation). The number of naked-eye satellites plummets as the Sun reaches 30−40° of elevation below the horizon. Specular flares and occultations by satellites are expected to cause only negligible effects on telescopic astronomical observations. The light trail caused by the satellite would ruin a small fraction (below the 1% level) of telescopic exposures using narrow to normal field imaging or spectroscopic techniques in the visible and near-infrared during the first and last hours of the night. Similarly, the thermal emission of the satellite would affect only a negligible fraction of the observations in the thermal infrared domain. However, wide-field exposures and long medium-field exposures would be affected at the 3% level during the first and last hours of the night. Furthermore, ultra-wide imaging exposures on a very large telescope (where saturation of the satellite trails has a ruinous effect on the detectors, such as those from the National Science Foundation’s Vera C. Rubin Observatory, formerly known as LSST), would be significantly affected, with 30–40% of such exposures being compromised during the first and last hours of the night. Coordination and collaboration between the astronomical community, satellite companies, and government agencies are therefore critical to minimise and mitigate the effect on astronomical observations, in particular on survey telescopes.

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Amrich, S., Š. Mackovjak, I. Strhárský, J. Baláž, and M. Hančikovský. "Design and construction of hardware and software for autonomous observations of Transient Luminous Events." Journal of Instrumentation 16, no. 12 (December 1, 2021): T12016. http://dx.doi.org/10.1088/1748-0221/16/12/t12016.

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Abstract Transient luminous events (TLE) are phenomena which are currently on the rise in terms of sightings. However, there is no widespread uniform method of their observation and subsequent image processing. Therefore, our project focuses on the design and construction of hardware that can record TLE. It consists of a low gain, colour, CMOS camera with a bright, wide lens connected to a small, power-efficient single board computer. The project also includes writing software to control the hardware. The software decides whether to capture or not and at what orientation there is the biggest chance to capture a TLE. The software can process and classify the created photos based on deep neural networks. As a final product, we have developed the whole apparatus from a hardware and software point of view and installed it at the Astronomical Observatory at Kolonica Saddle in Slovakia, Central Europe. The plan for the future is to make similar apparatuses to spread the observation network.

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SKIRMANTE, K., and G. JASMONTS. "Prediction of cometary OH maser emission in 1.6 GHz frequency band based on optical brightness." Astronomical and Astrophysical Transactions, Volume 33, Numéro 2 (August 8, 2022): 139–48. http://dx.doi.org/10.17184/eac.6476.

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Cometary OH maser emission evaluation was carried out to identify potentially bright comets for which OH maser emission were detectable in 1.6 GHz frequency range using Irbene RT-32 radio telescope. The evaluation model was based on the results of more than 3320 comets observations using data from optical and radio observations. Using the evaluation model, the correlation between optical brightness and radio flux density and correlation between flux density and OH production models was analyzed. In the research a prediction neural network model prototype was created to predict the comet brightness value in optical frequency range, based on the analyzed results from obtained correlation and characteristics of the comet. Based on the prediction model, the comet C/2021 A1 (Leonard) was observed in 1.6 GHz frequency band using Irbene RT-32 radio telescope. Spectral analysis using Fourier transform was applied to radio astronomical data from multiple observations related to weak cometary OH maser detection.

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VERTESI, JANET. "Instrumental images: the visual rhetoric of self-presentation in Hevelius's Machina Coelestis." British Journal for the History of Science 43, no. 2 (March 22, 2010): 209–43. http://dx.doi.org/10.1017/s0007087410000440.

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AbstractThis article places the famous images of Johannes Hevelius's instruments in his Machina Coelestis (1673) in the context of Hevelius's contested cometary observations and his debate with Hooke over telescopic sights. Seen thus, the images promote a crafted vision of Hevelius's astronomical practice and skills, constituting a careful self-presentation to his distant professional network and a claim as to which instrumental techniques guarantee accurate observations. Reviewing the reception of the images, the article explores how visual rhetoric may be invoked and challenged in the context of controversy, and suggests renewed analytical attention to the role of laboratory imagery in instrumental cultures in the history of science.

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Gezari, Daniel Y. "Observational Concerns and Techniques for High-Background Mid-Infrared (5–20 Micron) Array Imaging." Symposium - International Astronomical Union 167 (1995): 97–108. http://dx.doi.org/10.1017/s0074180900056333.

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Broadband observations at 5–20 micron with large ground-based telescopes are dominated by thermal background radiation from the telescope optics, instrument and sky. Astronomical sources typically contribute less than one percent of the total detected flux. In most cases the direct, unprocessed image of a bright source (before background subtraction) is indistinguishable from an image of blank sky (Fig. 1). This paper gives an overview of the fundamental concepts, conditions and limitations of high-background mid-infrared imaging. The techniques used to acquire and process the image data are summarized, illustrated with examples from our 58 × 62 pixel mid-infrared camera astronomy program.

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Elorrieta, Felipe, Susana Eyheramendy, and Wilfredo Palma. "Discrete-time autoregressive model for unequally spaced time-series observations." Astronomy & Astrophysics 627 (July 2019): A120. http://dx.doi.org/10.1051/0004-6361/201935560.

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Most time-series models assume that the data come from observations that are equally spaced in time. However, this assumption does not hold in many diverse scientific fields, such as astronomy, finance, and climatology, among others. There are some techniques that fit unequally spaced time series, such as the continuous-time autoregressive moving average (CARMA) processes. These models are defined as the solution of a stochastic differential equation. It is not uncommon in astronomical time series, that the time gaps between observations are large. Therefore, an alternative suitable approach to modeling astronomical time series with large gaps between observations should be based on the solution of a difference equation of a discrete process. In this work we propose a novel model to fit irregular time series called the complex irregular autoregressive (CIAR) model that is represented directly as a discrete-time process. We show that the model is weakly stationary and that it can be represented as a state-space system, allowing efficient maximum likelihood estimation based on the Kalman recursions. Furthermore, we show via Monte Carlo simulations that the finite sample performance of the parameter estimation is accurate. The proposed methodology is applied to light curves from periodic variable stars, illustrating how the model can be implemented to detect poor adjustment of the harmonic model. This can occur when the period has not been accurately estimated or when the variable stars are multiperiodic. Last, we show how the CIAR model, through its state space representation, allows unobserved measurements to be forecast.

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Bedding, Timothy R. "Optical and Infrared Interferometry." Symposium - International Astronomical Union 205 (2001): 447–52. http://dx.doi.org/10.1017/s0074180900221736.

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Interferometric techniques are at the forefront of modern astronomical instrumentation. A new generation of instruments are either operating or nearing completion, including arrays of small telescopes as well as the “big guns” (VLTI and Keck). A number of space interferometers for the detection of extra-solar planets are also being planned. I will review the current state of play and describe the latest developments in the field.

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Humphries, C. M., J. Davis, J. C. Bhattacharyya, O. Engvold, B. P. Fort, Hu Ning-Sheng, W. C. Livingston, et al. "Commission 9: Instruments and Techniques (Instruments Et Techniques)." Transactions of the International Astronomical Union 20, no. 1 (1988): 41–54. http://dx.doi.org/10.1017/s0251107x00006908.

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The technology leading to very large aperture telescopes and their optics has progressed well in the period since 1984 and plans for many new large aperture telescopes have been made. Focal plane instrumentation continues to become more sophisticated or more efficient: multi-object capabilities, automatic instrument control and operation, and increasing use of CCDs are examples of areas to which this applies. The proportion of time devoted to observations using two-dimensional photoelectronic detectors has grown substantially at many observatories, particularly with telescopes of moderate aperture; and the use of high quantum efficiency array detectors is now being extended into the infrared spectral region. Important advances have also been made in instrumentation and techniques for ground-based high angular resolution interferometry.

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Tang, Z. H., W. J. Jin, S. H. Wang, G. Pinigin, A. Shulga, N. Maigurova, and Yu Protsyuk. "Determination of Optical Positions for Extragalactic Radio Sources under the Collaboration Between SHAO and NAO." International Astronomical Union Colloquium 180 (March 2000): 57–60. http://dx.doi.org/10.1017/s0252921100000105.

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AbstractThe optical positions of 9 compact extragalactic radio sources have been determined by using the 1.56m, 1m and 60/90cm telescopes with CCDs in China and the Axial Meridian Circle at Nikolaev Astronomical Observatory since Jan. 1996 in a cooperative project between the two observatories. The instrumentation, observations and reduction are briefly described, and the preliminary results are presented. The comparison between the optical and radio positions for 9 sources are also given. More optical positions of radio sources are being processed.

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Chen, J. S. "Some Results of the BATC CCD Color Survey." Symposium - International Astronomical Union 179 (1998): 123–24. http://dx.doi.org/10.1017/s0074180900128372.

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The BATC (Beijing-Arizona-Taiwan-Connecticut) CCD color survey started 2 years ago. It is based on observations with the 60/90cm f/3 Schmidt Telescope of the Beijing Astronomical Observatory using a 2k×2k CCD and 15 intermediate band filters covering from 300nm to 1000nm to obtain the spectral energy distribution (SED) of all objects in 500 selected fields down to mV = 20 (Chen 1994). The basic framework of the survey including instrumentation, data acquisition system, archive data system, and the various steps of data reduction has been established. About 60 fields have been observed. Most fields are still short of observations in UV band. We are waiting for a new thinned CCD to improve the quantum efficiency.

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Scott, Paul J., and Alistair B. Forbes. "Mathematics for modern precision engineering." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, no. 1973 (August 28, 2012): 4066–88. http://dx.doi.org/10.1098/rsta.2011.0379.

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The aim of precision engineering is the accurate control of geometry. For this reason, mathematics has a long association with precision engineering: from the calculation and correction of angular scales used in surveying and astronomical instrumentation to statistical averaging techniques used to increase precision. This study illustrates the enabling role the mathematical sciences are playing in precision engineering: modelling physical processes, instruments and complex geometries, statistical characterization of metrology systems and error compensation.

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Fisher, J. Richard. "Hazards and Future Improvements to HI Surveys." Publications of the Astronomical Society of Australia 14, no. 1 (1997): 96–98. http://dx.doi.org/10.1071/as97096.

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AbstractMost radio astronomical observations are affected to some degree by man-made and natural interference. There are a few avoidance techniques that can reduce the impact of interference on the survey, but we must make quite significant advances in the understanding of our antennas and receivers and the interference itself before a substantial improvement can be expected. A major increase in the efficiency of future surveys will likely come from phased-array feeds, which have the potential for much closer beam spacings, greater antenna efficiency, and wider fields of view than current independent-feed arrays.

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Dai, Z. R., J. P. Bradley, T. P. Snow, and Z. L. Wang. "Transmission Electron Microscopy Studies of Natural Nanomaterials from the Solar System." Microscopy and Microanalysis 6, S2 (August 2000): 412–13. http://dx.doi.org/10.1017/s1431927600034553.

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It is widely appreciated that the study of (man-made) nanomaterials is a new frontier in materials science, but it is not well appreciated that (natural) nanomaterials represent a new frontier in meteoritics and planetary science [1]. During the next decade the nanogram to microgram quantities of extraterrestrial materials will be returned to Earth from a variety of solar system bodies including comets [2]. Studies of cometary interplanetary dust particles (IDPs) collected in the stratosphere, as well as mass spectrometry data from grains analyzed in-situ at comet Halley, suggest that the returned comet samples will be heterogeneous on a scale of nanometers [3, 4]. (A single 5-10μm diameter IDP may contain >106 individual grains and many different minerals (metal, carbonaceous phases, silicates, sulfides, etc.)). More recent observations of dust around stars, in interplanetary space, and at comet Hale-Bopp indicate that the predominant astronomical grain size is in the nanometer to submicrometer size range [5,6].

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Artola, Rodolfo, Martin Beroiz, Juan Cabral, Richard Camuccio, Moises Castillo, Vahram Chavushyan, Carlos Colazo, et al. "TOROS optical follow-up of the advanced LIGO–VIRGO O2 second observational campaign." Monthly Notices of the Royal Astronomical Society 493, no. 2 (January 3, 2020): 2207–14. http://dx.doi.org/10.1093/mnras/stz3634.

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ABSTRACT We present the methods and results of the optical follow-up, conducted by the Transient Optical Robotic Observatory of the South Collaboration, of gravitational wave events detected during the Advanced LIGO–Virgo second observing run (2016 November–2017 August). Given the limited field of view (∼100 arcmin) of our observational instrumentation, we targeted galaxies within the area of high localization probability that were observable from our sites. We analysed the observations using difference imaging, followed by a random forest algorithm to discriminate between real and spurious transients. Our observations were conducted using telescopes at Estación Astrofísica de Bosque Alegre, Cerro Tololo Inter-American Observatory, the Dr. Cristina V. Torres Memorial Astronomical Observatory, and an observing station in Salta, Argentina.

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Journal articles on the topic 'Instrumentation, Techniques, and Astronomical Observations'

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