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341. Pluto's observations between 1997 and 2010
ID:
ivo://CDS.VizieR/J/A+A/553/A14
Title:
Pluto's observations between 1997 and 2010
Short Name:
J/A+A/553/A14
Date:
21 Oct 2021
Publisher:
CDS
Description:
Because of Pluto's distance from the Sun, the Pluto system has not yet completed a revolution since its discovery, hence an uncertain heliocentric distance. In this paper, we present the fitting of our dynamical model ODIN (Orbite, Dynamique et Integration Numerique) to observations. The small satellites P4 and P5 are not taken into account. We fitted our model to the measured absolute coordinates (RA, DEC) of Pluto, and to the measured positions of the satellites relative to Pluto.
342. PNe in NGC 5128
ID:
ivo://CDS.VizieR/J/ApJS/88/423
Title:
PNe in NGC 5128
Short Name:
J/ApJS/88/423
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of planetary nebulae in the nearest giant elliptical galaxy NGC 5128. The catalog consists of positions and [O III]{lambda}5007 magnitudes for 785 planetary nebulae. This is the second largest catalog of planetaries, next only to that of the Milky Way. We also list the coordinates of 32 bright stars from the Guide Star Catalog and 80 additional reference stars in the survey fields for astrometric reference during future observations. The positions of the planetary nebulae are accurate to 0.2" with respect to the Guide Star Catalog in right ascension or declination.
343. Position catalogue of Swift XRT afterglows
ID:
ivo://CDS.VizieR/J/A+A/448/L9
Title:
Position catalogue of Swift XRT afterglows
Short Name:
J/A+A/448/L9
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of refined positions of 68 gamma ray burst (GRB) afterglows observed by the Swift X-ray Telescope (XRT) from the launch up to 2005 Oct. 16. This is a result of the refinement of the XRT boresight calibration. We tested this correction by means of a systematic study of a large sample of X-ray sources observed by XRT with well established optical counterparts. We found that we can reduce the systematic error radius of the measurements by a factor of two, from 6.5 to 3.2 (90% of confidence). We corrected all the positions of the afterglows observed by XRT in the first 11 months of the Swift mission. This is particularly important for the 37 X-ray afterglows without optical counterpart. Optical follow-up of dark GRBs, in fact, will be more efficient with the use of the more accurate XRT positions.
344. Position difference vectors and of the jets
ID:
ivo://CDS.VizieR/J/A+A/651/A64
Title:
Position difference vectors and of the jets
Short Name:
J/A+A/651/A64
Date:
22 Feb 2022
Publisher:
CDS
Description:
We aim to study the relative positions of quasar emission centers at different wavelengths in order to help link the various realizations of the International Celestial Reference System (ICRS), and to unveil systematic uncertainties and individual source behavior at different wavelengths. We based our study on four catalogs representing the ICRS, the ICRF3 positions in the three VLBI bands X, K, and Ka, and the Gaia EDR3 catalog in optical wavelengths. We complemented radio source positions with jet kinematics results from the MOJAVE team, allowing us to obtain jet directions on the sky. A six-parameter deformation model was used to remove systematic uncertainties present in the different catalogs. For a set of 194 objects common to the four catalogs and to the objects whose jet kinematics was studied by the MOJAVE team, we computed the orientation between positions at the different wavelengths and with respect to the directions of the jets. We find that the majority of these objects have their radio-to-optical vector along the jet, with the optical centroid downstream from the radio centroids, and that the K and Ka centroids are preferably upstream in the jet with respect to the X centroid, which is consistent with the paradigm of a simple core-jet model. For a population of multiwavelength positions aligned along the jet, astrometric information can therefore be used to measure the direction of the jet independently of imaging. In addition, we find several sources for which the optical centroid coincides with stationary radio features with a relatively high fraction of polarization, indicating optical emission dominated by a synchrotron process in the jet.
345. Position in M15
ID:
ivo://CDS.VizieR/J/A+AS/119/307
Title:
Position in M15
Short Name:
J/A+AS/119/307
Date:
21 Oct 2021
Publisher:
CDS
Description:
CCD observations of stars in the region of the globular cluster M15 have been used to obtain astrometric positions of 1092 stars in the central part of the cluster within the FK5 system. The purpose of this catalogue is to calibrate astrometrically CCD observations by means of measuring the positions of stars in M15. The comparison with other catalogues and with measurements of photographic plates of the central part of M15 indicates a mean accuracy of about 50 to 70mas for each star of our catalogue.
346. 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.
347. 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).
348. 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.
349. 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.
350. 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.

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