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- ID:
- ivo://CDS.VizieR/J/A+A/580/A76
- Title:
- Positions of satellites of giant planets
- Short Name:
- J/A+A/580/A76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The irregular satellites of the giant planets are believed to have been captured during the evolution of the solar system. Knowing their physical parameters, such as size, density and albedo is important to constrain where they came from and how they were captured. The best way to obtain these parameters are observations in situ by spacecrafts or from stellar occultations by the objects. Both techniques demand that the orbits are well known. We aimed to obtain good astrometric positions of irregular satellites in order to improve their orbits and ephemeris. We identified and reduced observations of several irregular satellites from three databases containing more than 8000 images obtained between 1992 and 2014 at three sites (Observatorio do Pico dos Dias, Observatoire de Haute-Provence and European Southern Observatory - La Silla). We used the software PRAIA (Platform for Reduction of Astronomical Images Automatically) to make the astrometric reduction of the CCD frames. The UCAC4 catalogue represented the International Celestial Reference System in the reductions. The identification of the satellites in the frames was done through their ephemerides as determined from the SPICE/NAIF kernels. Some procedures were taken to overcome missing or incomplete information (coordinates, date), mostly for the older images. We managed to obtain more than 6000 positions for 18 irregular satellites, being 12 of Jupiter, 4 of Saturn, 1 of Uranus (Sycorax) and 1 of Neptune (Nereid). For some satellites the number of obtained positions is more than 50% of that used in earlier orbital numerical integrations. Comparison of our positions with recent JPL ephemeris suggests the presence of systematic errors in the orbits for some of the irregular satellites. The most evident case was an error in the inclination of Carme.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2214
- Title:
- Positions of Saturn and its satellites in 2002-2006
- Short Name:
- J/AJ/136/2214
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents 2154 precise positions of Saturn and its major satellites from 359 CCD exposures taken with the 1m telescope at the Yunnan Observatory during the years 2002-2006.
- ID:
- ivo://CDS.VizieR/I/90
- Title:
- Positions of 502 Stars in Pleiades Region
- Short Name:
- I/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains the positions (equinox B1900.0 and epoch B1955.0) of 502 stars in a region of about 1.5 degrees square in the Pleiades cluster, centered on Eta Tau. These coordinates have been derived from measurements of stellar images obtained with 65 exposures of various durations on 14 photographic plates with two telescopes at McCormick Observatory and Van Vleck Observatory. The plates were reduced by the plate overlap method, which resulted in a high degree of systematic accuracy in the final positions. Data in the machine version include Hertzsprung number, color index, photovisual magnitude, right ascension and declination and their standard errors, proper motion, and differences between the present position and previous works. Data for exposures, plates, and images measured, present in the published catalog, are not included in the machine version.
- ID:
- ivo://CDS.VizieR/J/other/KFNT/15.483
- Title:
- Positions of Thebe and Amalthea
- Short Name:
- J/other/KFNT/15.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The file jovsat.dat contains 35 intersatellite positions of inner Jovian moons Thebe and Amalthea, derived from the observations made with the 2-m Zeiss RCC telescope of Terskol Observatory (Terskol peak, Northern Caucasus, long=42.50083{deg}, lat= 43.27427{deg}, h=3100m) in 1998. The Two-Channel Focal Reducer of the Max-Planck Institute for Aeronomy (MPAe,Germany) was used for acquisition of the images. We provide delta(alpha) and delta(delta) of Thebe and Amalthea with respect to the Galilean satellites, that were used as the reference points forming the reference direction on the frames. Astrometric topocentric coordinates J2000.0 of the Galilean satellites were used for scale and orientation angle determination. The array scale was corrected for differential refraction and differential aberration to first-order. All observed positions are compared with the theoretical ones.
- ID:
- ivo://CDS.VizieR/J/AJ/161/237
- Title:
- Positions of Triton with Sheshan Station telescope
- Short Name:
- J/AJ/161/237
- Date:
- 20 Jan 2022
- Publisher:
- CDS
- Description:
- The large time span and precise observational data of natural satellites is of great significance for updating their ephemerides and studying their dynamic characteristics. With the help of the new image-processing methods and the Gaia DR2 catalog, all CCD images of Triton taken with the 1.56m telescope of Shanghai Astronomical Observatory during 2005-2009 were reanalyzed. The median filtering algorithm is used for image preprocessing to remove the influence of the halo of Neptune, and an upgraded modified moment, called the intensity-square-weighted centroiding method, is applied to determine the centroids of the stars and Triton. A total of 2299 positions of Triton were obtained, including 263 new observed positions and 2036 updated observed positions. Such five-year time span data with high precision will be very helpful to improve the orbit parameters of Triton.
- ID:
- ivo://CDS.VizieR/IX/6
- Title:
- Positions of X-Ray Sources, 2nd ed.
- Short Name:
- IX/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog is a superset of the X-ray position list in the Astronomical Almanac (1983). It is designed as an aid to observers. Either one or two positions are given for each X-ray source. Identified counterparts are included for many sources.
- ID:
- ivo://CDS.VizieR/J/A+A/312/1031
- Title:
- Positions & proper motions of radio stars
- Short Name:
- J/A+A/312/1031
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The optical positions of 63 extragalactic nebulae measured in the frame defined by the annual series of Carlsberg Meridian Catalogues Nos 1-8 are compared with their VLBI radio positions in the International Celestial Reference Frame. The differences between these radio and optical positions are interpreted as showing the global distortion of the Carlsberg optical frame, which is linked to that of the FK5. North of the equator the Carlsberg optical frame is within 0.05" of the ICRF; but south of the equator it deviates by 0.07" in right ascension and 0.10" in declination. The general form of the deviations follow those of the FK5, which are revealed in a recent comparison of FK5 with a preliminary version of the Hipparcos catalogue (H30).
- ID:
- ivo://CDS.VizieR/I/312
- Title:
- PPMX Catalog of positions and proper motions
- Short Name:
- I/312
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- PPM-Extended (PPMX) is a catalogue of 18,088,919 stars containing astrometric and photometric information. Its limiting magnitude is about 15.2 in the GSC photometric system. PPMX consists of three parts: a) a survey complete down to R_U_=12.8 in the magnitude system of UCAC2; b) additional stars of high-precision proper motions, and c) all other stars from GSC 1.2 identified in 2MASS. The typical accuracy of the proper motions is 2mas/y for 66 percent of the survey stars (a) and the high-precision stars (b), and about 10mas/y for all other stars. PPMX contains photometric information from ASCC-2.5 and 2MASS.
- ID:
- ivo://CDS.VizieR/J/A+A/459/981
- Title:
- Precession-nutation procedures (IAU 2006)
- Short Name:
- J/A+A/459/981
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 2006 IAU General Assembly has adopted the P03 model of Capitaine et al. (2003A&A...412..567C) recommended by the WG on precession and the ecliptic (Hilton et al., 2006, Celest. Mech. Dyn. Astron. 94, 351) to replace the IAU 2000 model, which comprised the Lieske et al. (1977A&A....58....1L) model with adjusted rates. Practical implementations of this new "IAU 2006" model are therefore required, involving choices of procedures and algorithms. The purpose of this paper is to recommend IAU 2006 based precession-nutation computing procedures, suitable for different classes of application and achieving high standards of consistency.
