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Start Over Subject astrometry Validation Level 2
411. Position of Uranian satellites
ID:
ivo://CDS.VizieR/J/A+AS/107/559
Title:
Position of Uranian satellites
Short Name:
J/A+AS/107/559
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
412. Position of Uranian satellites
ID:
ivo://CDS.VizieR/J/A+A/454/683
Title:
Position of Uranian satellites
Short Name:
J/A+A/454/683
Date:
21 Oct 2021
Publisher:
CDS
Description:
Puck, a faint satellite very close to Uranus' planet, was discovered by Voyager 2 Spacecraft images in 1986. Ever since then, few observations from Earth have been made. This prompted us to start a program of systematic observations of this satellite with the 1.6m telescope at the Laboratorio Nacional de Astrofisica/MCT (Itajuba, Brazil). The success of the observations is mainly due to the use of a Coronagraph developed at Observatorio Nacional/MCT (Rio de Janeiro, Brazil). This article presents astrometric positions obtained from Earth observations of Puck and of the five major Uranian satellites for four nights in 2004. Those positions are compared to the theoretically calculated positions from JPL Development Ephemeris. For Puck, the root mean square (rms) of the mean residual was found to be 84 milliarcseconds (mas). The stars' USNO-A2.0 catalog (<I/252>) was used as a reference system for the astrometric calibration.
413. Positions and Proper Motions in alpha Per cluster
ID:
ivo://CDS.VizieR/I/68A
Title:
Positions and Proper Motions in alpha Per cluster
Short Name:
I/68A
Date:
21 Oct 2021
Publisher:
CDS
Description:
A list of positions and proper motions is given for 2027 stars of magnitude 7.5 to 12.5 within a radius of 3.5 deg. of alpha Persei. The values are poor for stars fainter than 11. The present list supersedes the microfiche edition (catalogue I/68/) which was described in the Bull. Inform. CDS 18, 81 (1980).
414. Positions and Proper Motions - North
ID:
ivo://CDS.VizieR/I/146
Title:
Positions and Proper Motions - North
Short Name:
I/146
Date:
21 Oct 2021
Publisher:
CDS
Description:
PPM North gives J2000 positions and proper motions of 181731 stars north of -2.5 degrees declination. Its main purpose is to provide a convenient, dense, and accurate net of astrometric reference stars that represents the new IAU (1976) coordinate system on the sky. The mean epoch is near 1931. The average mean errors of the positions and proper motions are 0.27" and 0.43"/cen. On the average six measured positions are available per star; 1064 stars do not have sufficient redundancies to resolve discrepancies. In addition to the positions and proper motions, the PPM (North) contains the BD number, the magnitude, the spectral type, the number of positions included, the mean error of each component of the position and proper motion, the weighted mean epoch in each coordinate, the numbers in the SAO, HD, and AGK3 catalogs, and various standard notes. In addition a number of individual notes are given in the introduction. See file desc.txt for complete explanations provided by the authors.
415. Positions and Proper Motions - South
ID:
ivo://CDS.VizieR/I/193
Title:
Positions and Proper Motions - South
Short Name:
I/193
Date:
21 Oct 2021
Publisher:
CDS
Description:
PPM South gives positions and proper motions of 197179 stars south of about -2.5 degrees declination. Its main purpose is to provide a convenient, dense and accurate net of astrometric reference stars on the southern celestial hemisphere. This net is designed to represent as closely as possible the new IAU (1976) coordinate system on the sky, as defined by the FK5 star catalogue (Fricke et al., 1988). In other words, it is a representation of this system at higher star densities and fainter magnitudes. PPM South is the southern-hemisphere complement to the PPM Star Catalogue (Roeser and Bastian, 1991), which covers the northern hemisphere, plus a strip between the equator and about -2.5 degrees declination. At the border line a continuous transition between the northern and southern part was tailored in such a way that no overlap, nor gaps, nor double entries occurred. See file "desc.txt" for complete explanations provided by the authors.
416. Positions for 179 Swift X-ray afterglows
ID:
ivo://CDS.VizieR/J/AJ/133/1027
Title:
Positions for 179 Swift X-ray afterglows
Short Name:
J/AJ/133/1027
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a refined catalog for the positions of 179 gamma-ray burst (GRB) X-ray afterglows observed by the X-Ray Telescope (XRT) on Swift prior to 2006 November 1. The positions are determined by detecting X-ray field sources in the deep X-ray images and comparing the centroids to those of optical sources in the Digitized Sky Survey red2 catalog or the Sloan Digital Sky Survey Data Release 5 catalog. Half of the 90% confidence error region radii are <2.2". The error regions areas are typically ~4 times smaller than the best XRT team error regions, although the positions require deep X-ray integration (>20ks) and cannot be generated nearly as rapidly after the GRB. The positions derived for >90% of 77 bursts with optical afterglows are consistent with the optical transient positions, without the need for systematic error. About 20% of the afterglow positions require a sizable shift in the Swift satellite aspect. We discuss the optical/X-ray properties of the field sources and discuss the implications of the frame offsets for studies of optically dark GRBs.
417. Positions of giant radio galaxies
ID:
ivo://CDS.VizieR/J/A+A/374/861
Title:
Positions of giant radio galaxies
Short Name:
J/A+A/374/861
Date:
21 Oct 2021
Publisher:
CDS
Description:
In tablea1.dat, we present the WENSS selected candidate GRGs after removing sources identified as non-GRGs on basis of optical data. In tablea2.dat, we present the log of the spectroscopic observations of GRG andidates in our sample. In tablea3.dat, we present properties of the radio cores and the optical identifications of the spectroscopically observed giant radio sources, and of the confirmed giant sources B1144+352, B1245+676 and B1310+451. We provide the name of the radio source in IAU notation, the observation used to determine the radio core position and its flux density and the radio core position in right ascension and declination, respectively, in B1950.0 coordinates. The radio positions have been obtained by fitting a Gaussian in the radio map. We further provide the integrated flux density at 1.4GHz of the radio core, the position of the optical identification in right ascension and declination, respectively, in B1950.0 coordinates, obtained from fitting a Gaussian in the available optical image and the magnitude of the identification in the red (POSS-E) band of the Palomar survey. The magnitudes for sources weaker than 15.0 have been obtained from the APM catalogue and are estimated to be accurate to 0.5 mag. For brighter sources, we have measured the magnitudes directly from the digitized POSS-I frames using the photometric calibration for stars available from the STScI WWW-pages and through the getimage-2.0 plate retrieval software. Typical uncertainties in these values are estimated to be large, at least 1mag. In tablea4.dat, further radio properties of the sources in tablea3.dat. We present the integrated flux density of the source at 325MHz from the Westerbork Northern Sky Survey (WENSS) (unless stated otherwise), the integrated flux density at 1400MHz from the NVSS, the spectral index between 325 and 1400MHz, the redshift of the host galaxy, the angular size of the radio source in arcminutes, the resulting projected linear size in Mpc (using H_0=50km/s/Mpc, q_0_=0.5) and the radio luminosity at an emitted frequency of 325MHz.
418. Positions of high-redshift luminous quasars
ID:
ivo://CDS.VizieR/VII/149
Title:
Positions of high-redshift luminous quasars
Short Name:
VII/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present finding charts and J2000 positions accurate to ~1" for the 528 high-redshift (z>1), luminous (M_v_<-25.5) quasars investigated in the Hubble Space Telescope Snapshot Survey. The information was produced with the Space Telescope Science Institute's Astrometric Support Program.
419. Positions of satellites of giant planets
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.
420. Positions of Saturn and its satellites in 2002-2006
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.

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