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1.
The IAU Meteor Data Center in Lund has acted as a central depository for meteor orbits obtained by photographic, video and radar techniques. The database of precisely reduced photographic meteors contains data on 4581 meteor orbits obtained by 17 different stations or groups in the period 1936–1996. The orbital and geophysical data are available in two separate files as well as in an alternative file with the merged data. In various studies of meteoroid streams as well as in studies of the sporadic meteor background, it is often necessary to utilize both the orbital and the geophysical data files. Since the database is a compilation of partial, not perfectly compatible catalogues from many observing stations, the merging of parameters from one data set to another may sometimes present problems. The present contribution is a note on some problems encountered in the merging procedure. Moreover, it is evident that the database includes a small amount of erroneous data – either in the observations or in the subsequent data reductions. The latter error is not surprising in view of the lack of modern computers at several stations in the past. A final, corrected version of the IAU MDC Lund photographic meteor orbits (eq. 2000.0) can now be requested through the homepage of the Astronomical Institute, Slovak Academy of Sciences (http://www.astro.sk/~ne/IAUMDC/Ph2003/database.html).  相似文献   

2.
3.
In 2007, a companion with planetary mass was found around the pulsating subdwarf B star V391 Pegasi with the timing method, indicating that a previously undiscovered population of substellar companions to apparently single subdwarf B stars might exist. Following this serendipitous discovery, the EXOTIME (http://www.na.astro.it/~silvotti/exotime/) monitoring program has been set up to follow the pulsations of a number of selected rapidly pulsating subdwarf B stars on time scales of several years with two immediate observational goals:
  1. determine $\dot{P}$ of the pulsational periods P
  2. search for signatures of substellar companions in O–C residuals due to periodic light travel time variations, which would be tracking the central star’s companion-induced wobble around the centre of mass
These sets of data should therefore, at the same time, on the one hand be useful to provide extra constraints for classical asteroseismological exercises from the $\dot{P}$ (comparison with “local” evolutionary models), and on the other hand allow one to investigate the preceding evolution of a target in terms of possible “binary” evolution by extending the otherwise unsuccessful search for companions to potentially very low masses. While timing pulsations may be an observationally expensive method to search for companions, it samples a different range of orbital parameters, inaccessible through orbital photometric effects or the radial velocity method: the latter favours massive close-in companions, whereas the timing method becomes increasingly more sensitive toward wider separations. In this paper we report on the status of the on-going observations and coherence analysis for two of the currently five targets, revealing very well-behaved pulsational characteristics in HS?0444+0458, while showing HS?0702+6043 to be more complex than previously thought.  相似文献   

4.
The original coronal index of the solar activity (CI) has been constructed on the basis of ground-based measurements of the intensities of the coronal line of 530.3 nm (Rybanský in Bull. Astron. Inst. Czechoslov., 28, 367, 1975; Rybanský et al. in J. Geophys. Res., 110, A08106, 2005). In this paper, CI is compared with the EUV measurements on the CELIAS/SEM equipment based on the same idea as the original idea of the coronal index. The correlation is very good for the period 1996?–?2005 (r=0.94 for daily values). The principal result of this paper is the introduction of the modified coronal index (MCI) which in all uses and contexts can replace the existing CI index. Daily MCI values extend over a time period of six solar activity cycles. Future MCI measurements will be derived from more reliable measurements made by space-based observatories that are not influenced by the weather. MCI measurements are and will continue to be archived at the web site of the Slovak Central Observatory in Hurbanovo ( http://www.suh.sk/obs/vysl/MCI.htm ).  相似文献   

5.
We present a novel approach to quality control during the processing of astronomical data. Quality control in the Astro-WISE Information System is integral to all aspects of data handing and provides transparent access to quality estimators for all stages of data reduction from the raw image to the final catalog. The implementation of quality control mechanisms relies on the core features in this Astro-WISE Environment (AWE): an object-oriented framework, full data lineage, and both forward and backward chaining. Quality control information can be accessed via the command-line awe-prompt and the web-based Quality-WISE service. The quality control system is described and qualified using archive data from the 8-CCD Wide Field Imager (WFI) instrument (http://www.eso.org/lasilla/instruments/wfi/) on the 2.2-m MPG/ESO telescope at La Silla and (pre-)survey data from the 32-CCD OmegaCAM instrument (http://www.astro-wise.org/~omegacam/) on the VST telescope at Paranal.  相似文献   

6.
The He, C, N, and O abundances in more than 120 planetary nebulae (PNe) of our Galaxy and the Magellanic Clouds have been redetermined by analyzing new PNe observations. The characteristics of PNe obtained by modeling their spectra have been used to compile a new catalog of parameters for Galactic and extragalactic PNe, which is accessible at http://www.astro.spbu.ru/staff/afk/GalChemEvol.html. The errors in the parameters of PNe and their elemental abundances related to inaccuracies in the observational data have been analyzed. The He abundance is determined with an accuracy of 0.06 dex, while the errors in the C, N, and O abundances are 0.1–0.2 dex. Taking into account the inaccuracies in the corrections for the ionization stages of the elements whose lines are absent in the PNe spectra increases the errors in the He abundance to 0.1 dex and in the C, N, and O abundances to 0.2–0.3 dex. The elemental abundances in PNe of various Galactic subsystems and the Magellanic Clouds have been analyzed. This analysis suggests that the Galactic bulge objects are similar to type II PNe in Peimbert’s classification, whose progenitor stars belong to the thin-disk population with ages of at least 4–6 Gyr. A similarity between the elemental abundances in PNe of the Magellanic Clouds and the Galactic halo has been established.  相似文献   

7.
A central depository for meteor orbits obtained by photographic techniques, as a part of the IAU Meteor Data Center, was moved to the Astronomical Institute of the Slovak Academy of Sciences in Bratislava in 2001. The current version of the catalogue contains data on 4581 meteor orbits obtained by 17 different stations or groups from the period 1936 to 1996. Since 1996 a few huge campaigns were organised including very successful Leonids and Perseids. That is why we would prepare a new more complete version of the database. The main aim of this paper is a call to the observers of meteors having new or recalculated/remeasured data on photographic meteors to send them to the MDC, where after a check and consultations with the observer, the orbits will be included in the database.  相似文献   

8.
We have designed and implemented a novel way to process wide-field astronomical data within a distributed environment of hardware resources and humanpower. The system is characterized by integration of archiving, calibration, and post-calibration analysis of data from raw, through intermediate, to final data products. It is a true integration thanks to complete linking of data lineage from the final catalogs back to the raw data. This paper describes the pipeline processing of optical wide-field astronomical data from the WFI (http://www.eso.org/lasilla/instruments/wfi/) and OmegaCAM (http://www.astro-wise.org/~omegacam/) instruments using the Astro-WISE information system (the Astro-WISE Environment or simply AWE). This information system is an environment of hardware resources and humanpower distributed over Europe. AWE is characterized by integration of archiving, data calibration, post-calibration analysis, and archiving of raw, intermediate, and final data products. The true integration enables a complete data processing cycle from the raw data up to the publication of science-ready catalogs. The advantages of this system for very large datasets are in the areas of: survey operations management, quality control, calibration analyses, and massive processing.  相似文献   

9.
At the end of the workshop the contributors bounced some ideas aroundand shared their thoughts about maximizing the advancement thata study of Sakurai's Object can provide. In particular it was resolvedto set up a web site http://astro.uibk.ac.at/sakurai, witha finding chart and a record of data obtained, and to maintain theoriginal workshop web site at http://www.astro.keele.ac.uk/sakurai. Observers and theoreticians are urged to consult,and to contribute to, this resource.  相似文献   

10.
The Astronomical Institute of the Slovak Academy of Sciences has published the intensities, recalibrated with respect to a common intensity scale, of the 530.3 nm (Fe xiv) green coronal line observed at ground-based stations up to the year 2008. The name of this publication is Homogeneous Data Set (HDS). We have developed a method that allows one to successfully substitute the ground-based observations by satellite observations and, thus, continue with the publication of the HDS. For this purpose, the observations of the Extreme-ultraviolet Imaging Telescope (EIT), onboard the Solar and Heliospheric Observatory (SOHO) satellite, were exploited. Among other data the EIT instrument provides almost daily 28.4 nm (Fe xv) emission-line snapshots of the corona. The Fe xiv and Fe xv data (4051 observation days) taken in the period 1996?–?2008 have been compared and good agreement was found. The method to obtain the individual data for the HDS follows from the correlation analysis described in this article. The resulting data, now under the name of Modified Homogeneous Data Set (MHDS), are identical up to 1996 to those in the HDS. The MHDS can be used further for studies of the coronal solar activity and its cycle. These data are available at http://www.suh.sk .  相似文献   

11.
This study of the orbital evolution and encounters of distant satellites of planets is aimed at determining their origin. It is also important for understanding the distribution of matter in the early stages of evolution of the Solar System. The mutual encounter of satellites is very weak because of their small sizes and masses. However, at very large time intervals, mutual encounter can be quite close to significantly changing the orbits of satellites. In order to study these factors, we have developed a special method and computer programs. For 107 distant satellites of Jupiter, Saturn, Uranus, and Neptune, motion parameters have been determined using observational data. On the basis of these parameters, a numerical integration of the equations of motion of the satellites has been carried out in time intervals of several thousand years. Using the original method of frequency analysis, we found rather simple analytical functions that correspond to the results of the numerical integration and make it possible to calculate orbital parameters at any time during a long interval. These tools make it possible to conduct extensive studies of changes in the form and relative position in space of the orbits of distant satellites of Jupiter, Saturn, Uranus, and Neptune. Several examples illustrate the possibilities offered by these tools. The computer software in the form of a service ephemeris of satellite orbits over a long interval of time is available via the Internet (http://www.sai.msu.ru/neb/nss/evolu0e.htm) on the website of the State Astronomical Institute of the Moscow State University.  相似文献   

12.
The catalogue (astrometric and astrophysical parameters) of 555200 stars with high proper motions (more than 0.04″/year) was compiled on the basis of original definitions from the catalogues FONAK1.1, Hipparcos, Tycho-2, UCAC2, CMC (STAR 11), PPM, NPM1, NPM2, XZ80Q, Pul-3, Pul2, NLTT, GCVS, LHS, Lowell Proper Motion Service, and Bruce Proper Motion Service as well as of the information from about 770 other published sources—ftp://ftp.mao.kiev.ua/pub/astro/h-pms2.dat.  相似文献   

13.
We provide an overview of the main results obtained as part of the programs for astrometric observations of bodies in the Solar system at the Pulkovo Observatory over the period 1898–2005. We summarize the results of photographic observations and show new possibilities for astrometric observations in connection with the transition to CCD detectors on Pulkovo instruments. Observing and data reduction techniques are considered. A database with Pulkovo observations of bodies in the Solar system has been created and opened to users. The database is accessible at http://www.puldb.ru.  相似文献   

14.
Many papers are devoted to the prediction of radiation conditions on board of a spacecraft (Pichkhadze et al., 2004; Khamidullina et al., 2008; 2012), and a number of software systems for corresponding calculations have been developed: the US information system CREME96 (https://creme.isde.vander-bilt.edu/); European SPENVIS (http://www.spenvis.oma.be/intro.php); Russian SEREIS (Kuznetsov et al., 2001; Model’ kosmosa, 2007) and COSRAD (http://cosrad.sinp.msu.ru/manual.html; Kuznetsov et al., 2011) based on the models of the radiation environment in near-Earth space (Bashkirov et al., 1998; Nymmik, 2004; Model’ kosmosa, 2007; Kuznetsov et al., 2011). In this paper we propose a simple calculation algorithm of short-term (for a few days) forecasting of dynamics of the radiation dose on the International Space Station (ISS) in radiation environment undisturbed by solar proton events. This algorithm does not use radiation environment models and detailed ballistic calculations, while it uses data of the onboard radiation monitoring system (RMS) and empirical relations, obtained for ISS orbital motion.  相似文献   

15.
A comparative analysis of both long-period deviations in the duration of a day from the standard (86400 s) and solar activity during the years 1700–2003 has been conducted. The comparative analysis was based on the average annual data on LOD (http://hpiers.obspm.fr/eop-pc/) and the number of sunspots W (http://www.wdcb.ru/stp/). The analysis was aimed at studying the evolution of the solar-terrestrial relationship under conditions of insufficient physical data on the origin and interaction of such oscillations in irregular variations in the duration of a day and in parameters characterizing solar activity. The analysis was conducted using three methods, i.e., the periodogram method, the method of exponential data approximation (the Prony method), and the technique of wavelet data transformation. A comparison of the analysis results allows the general conclusion to be drawn that such variations over ~11-yr-long and ~22-yr-long periods are coherent in the data on LOD and W. The amplitude of a squared absolute value of coherence comprises 72% for 11-year and 74% for 22-year variations.  相似文献   

16.
A cross index list of 493 200 stars with proper motions higher than 0.04″/yr (ftp://ftp.mao.kiev.ua/pub/astro/c-ihpms2) was compiled on the basis of the original determinations for the FONAK1.1 catalog stars, the data from the Hipparcos, Tycho-2, UCAC2, CMC (STAR 11), PPM, NPM1, NPM2, XZ80Q, Pul-3, PUL2, GCVS, NLTT, LHS, Lowell Proper Motion, and Bruce Proper Motion catalogs, as well as the data published in other sources.  相似文献   

17.
We compiled a catalog (containing astrometric and astrophysical characteristics) of 4 302 200 stars with high proper motions (no less than 40 mas/year) using original measurements of proper motions of stars from the catalogs FONAK 1.1, HIPPARCOS, ??Tycho-2,?? UCAC2,3, CMC (STAR 11), PPM, PPMX, NPM1, NPM2, XZ80Q, Pul-3, Pul2, NLTT, GCVS, LHS, ??Lowell Proper Motion,?? and ??Bruce Proper Motion,?? as well as some data from approximately 800 other published sources. The location of our catalog is ftp://ftp.mao.kiev.ua/pub/astro/h-pms3.dat.  相似文献   

18.
An interferometer antenna system to observe polarized radio emission from the solar corona at different frequencies in the range 30?–?110 MHz has been commissioned recently by the Indian Institute of Astrophysics at the Gauribidanur Radio Observatory (latitude 13°3612′′N and longitude 77°2707′′E), about 100 km north of Bangalore (http://www.iiap.res.in/centres_radio.htm). This paper describes the antenna system, associated analog/digital receiver setup, calibration scheme, and preliminary results.  相似文献   

19.
A new database of all astrometric observations of moons of asteroids is offered. It has a simple structure and is accessible through the Internet. Regular database updating is provided when new observational results occur in publications. The database is located at the sites of the Natural Satellites Data Center created as a result of collaboration between the Sternberg Astronomical Institute of Moscow State University and the Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE). The database addresses in the Internet are https://doi.org/www.sai.msu.ru/neb/nss/indexr.htm and https://doi.org/nsdb.imcce.fr/obsposrespectively. On entering these sites, we need to select one of three languages, the Observation item, and the Astrometric positions of asteroids with moons item. The observational data are provided here with explanations and hyperlinks to the publications in the bibliographic database SAO/NASA Astrophysics Data System (ADS) Abstract Service.  相似文献   

20.
The sets of photographic observations of the Galilean satellites of Jupiter taken at the Abastumani Astrophysical Observatory of the Academy of Sciences of Georgia are analyzed here. Positional observations of the system of Jupiter were made in the period from 1985 to 1994 with the use of the double Zeiss astrograph in order to determine the exact coordinates of Jupiter and its satellites. The accurate positions of the satellites and Jupiter itself, as well as their stellar (equatorial) coordinates relative to the stars of the currently available catalogs and the relative ??satellite ?? satellite?? coordinates were obtained from the observations. From the comparison of the observation results with the modern theories of motion of satellites, the accuracy in determining the positions of the satellites and Jupiter was analyzed. The results of observations are presented in the Pulkovo database of observations of Solar System bodies that is accessible to users at http://www.puldb.ru.  相似文献   

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