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71. Astrometry of the main satellites of Uranus
ID:
ivo://CDS.VizieR/J/A+A/582/A8
Title:
Astrometry of the main satellites of Uranus
Short Name:
J/A+A/582/A8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We determine accurate positions of the main satellites of Uranus: Miranda, Ariel, Umbriel, Titania, and Oberon. Positions of Uranus, as derived from those of these satellites, are also determined. The observational period spans from 1992 to 2011. All runs were made at the Pico dos Dias Observatory, Brazil. We used the software called Platform for Reduction of Astronomical Images Automatically (PRAIA) to perform a digital coronography to minimise the influence of the scattered light of Uranus on the astrometric measurements and to determine accurate positions of the main satellites. The positions of Uranus were then indirectly determined by computing the mean differences between the observed and ephemeris positions of these satellites. A series of numerical filters was applied to filter out spurious data. These filters are mostly based on (a) the comparison between the positions of Oberon with those of the other satellites and on (b) the offsets as given by the differences between the observed and ephemeris positions of all satellites. We have, for the overall offsets of the five satellites, -29mas (+/-63mas) in right ascension and -27mas (+/-46mas) in declination. For the overall difference between the offsets of Oberon and those of the other satellites, we have +3mas (+/-30mas) in right ascension and -2mas (+/-28mas) in declination. Ephemeris positions for the satellites were determined from DE432+ura111.
72. Astrometry of the Saturnian satellites 2004-12
ID:
ivo://CDS.VizieR/J/A+A/575/A73
Title:
Astrometry of the Saturnian satellites 2004-12
Short Name:
J/A+A/575/A73
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Cassini spacecraft has been orbiting Saturn since 2004 returning images of satellites with astrometric resolution as high as few hundreds of meters. The images that were taken by the Narrow Angle Camera (NAC) of Image Science Subsystem (ISS) instrument on board Cassini, were used in this work for the purpose of astrometry. We applied the same method that was previously developed to reduce Cassini NAC images of Mimas and Enceladus. We provide 5240 astrometric positions in right ascension and declination of the satellites: Tethys, Dione, Rhea, Iapetus, and Phoebe, using images that were taken by Cassini NAC between 2004 and 2012. Mean residuals compared to the JPL ephemeris SAT365 are of the order of hundreds of meters with standard deviations of the order of few kilometers. Frequency analysis of the residuals shows the remaining non-modeled effects of satellites on others.
73. Astrometry of 3 vdBH open clusters
ID:
ivo://CDS.VizieR/J/other/NewA/36.70
Title:
Astrometry of 3 vdBH open clusters
Short Name:
J/other/NewA/36.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of a study that combines photometry and astrometry for the open clusters vdB80, vdB85 and vdB130. We apply a model which analyses the proper motion distribution and the stellar density to find the kinematic parameters and stellar membership in the region of the mentioned open clusters. The astrometric data are obtained from UCAC4 catalogue.
74. Astrometry&photometry for late-type dwarfs&subdwarfs
ID:
ivo://CDS.VizieR/J/AJ/154/147
Title:
Astrometry&photometry for late-type dwarfs&subdwarfs
Short Name:
J/AJ/154/147
Date:
21 Oct 2021
Publisher:
CDS
Description:
New, updated, and/or revised CCD parallaxes determined with the Strand Astrometric Reflector at the Naval Observatory Flagstaff Station are presented. Included are results for 309 late-type dwarf and subdwarf stars observed over the 30+ years that the program operated. For 124 of the stars, parallax determinations from other investigators have already appeared in the literature and we compare the different results. Also included here are new or updated VI photometry on the Johnson-Kron-Cousins system for all but a few of the faintest targets. Together with 2MASS JHK_s_ near-infrared photometry, a sample of absolute magnitude versus color and color versus color diagrams are constructed. Because large proper motion was a prime criterion for targeting the stars, the majority turn out to be either M-type subdwarfs or late M-type dwarfs. The sample also includes 50 dwarf or subdwarf L-type stars, and four T dwarfs. Possible halo subdwarfs are identified in the sample based on tangential velocity, subluminosity, and spectral type. Residuals from the solutions for parallax and proper motion for several stars show evidence of astrometric perturbations.
75. Astrometry & radial velocity, Alpha Centauri system
ID:
ivo://CDS.VizieR/J/AJ/162/14
Title:
Astrometry & radial velocity, Alpha Centauri system
Short Name:
J/AJ/162/14
Date:
14 Mar 2022 06:46:54
Publisher:
CDS
Description:
Alpha Centauri A is the closest solar-type star to the Sun and offers the best opportunity to find and ultimately to characterize an Earth-sized planet located in its habitable zone. Here, we describe initial results from an Atacama Large Millimeter/submillimeter Array (ALMA) program to search for planets in the {alpha} Cen AB system using differential astrometry at millimeter wavelengths. Our initial results include new absolute astrometric measurements of the proper motion, orbital motion and parallax of the {alpha} Cen system. These lead to an improved knowledge of the physical properties of both {alpha} Cen A and B. Our estimates of ALMA's relative astrometric precision suggest that we will ultimately be sensitive to planets of a few tens of Earth mass in orbits from 1 to 3au, where stable orbits are thought to exist.
76. Astrophysical supplements to ASCC-2.5
ID:
ivo://CDS.VizieR/J/AN/325/740
Title:
Astrophysical supplements to ASCC-2.5
Short Name:
J/AN/325/740
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue of stars in the Galactic open cluster areas (CSOCA) is the result of the kinematic (proper motion), photometric and spatial member selection of stars listed in the homogeneous All-sky Compiled Catalogue of 2.5 Million Stars (ASCC-2.5, Cat. <I/280>) within 520 areas with open clusters selected from an on-line release 2.0 of catalogue by Dias et al. (2004, http://www.astro.iag.usp.br/~wilton, Cat. VII/229). The areas represent quadratic fields centered at adopted cluster centers with side lengths of a_cl_[deg]=2*(r_cl_+0.1), where r_cl_ is the determined angular radius of the cluster. For clusters with r_cl_<0.4{deg}, a_cl_=1{deg}. In every cluster area the CSOCA contains the complete list of the ASCC-2.5 stars. The catalog includes accurate J2000 equatorial coordinates, proper motions in the Hipparcos system, BV photometric data in the Johnson system, proper motion, photometric and spatial membership probabilities, and angular distances from the cluster centers for all included stars. If available, trigonometric parallaxes, multiplicity and variability flags from the ASCC-2.5, spectral types (from the ASCC-2.5 or the Tycho-2 Spectral Type Catalog <III/231>), and radial velocities with their errors from the Catalogue of Radial Velocities of Galactic Stars with high precision Astrometric Data (CRVAD, <III/239>) are also given. Since some cluster areas overlap each other some stars are included in the CSOCA several times. The catalogue contains 171319 entries for 149849 stars. Entries are sorted in right ascension J2000 order.
77. BDKP. III. Parallaxes for 70 ultracool dwarfs
ID:
ivo://CDS.VizieR/J/ApJ/752/56
Title:
BDKP. III. Parallaxes for 70 ultracool dwarfs
Short Name:
J/ApJ/752/56
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report parallax measurements for 70 ultracool dwarfs (UCDs) including 11 late-M, 32 L, and 27 T dwarfs. In this sample, 14 M and L dwarfs exhibit low surface gravity features, 6 are close binary systems, and 2 are metal-poor subdwarfs. We combined our new measurements with 114 previously published UCD parallaxes and optical-mid-IR photometry to examine trends in spectral-type/absolute magnitude, and color-color diagrams. We report new polynomial relations between spectral type and M_JHK_. Including resolved L/T transition binaries in the relations, we find no reason to differentiate between a "bright" (unresolved binary) and a "faint" (single source) sample across the L/T boundary. Isolating early T dwarfs, we find that the brightening of T0-T4 sources is prominent in M_J_ where there is a [1.2-1.4] mag difference. A similar yet dampened brightening of [0.3-0.5] mag happens at M_H_ and a plateau or dimming of [-0.2 to -0.3] mag is seen in M_K_. Comparison with evolutionary models that vary gravity, metallicity, and cloud thickness verifies that for L into T dwarfs, decreasing cloud thickness reproduces brown dwarf near-IR color-magnitude diagrams. However we find that a near constant temperature of 1200 +/-100 K along a narrow spectral subtype of T0-T4 is required to account for the brightening and color-magnitude diagram of the L-dwarf/T-dwarf transition. There is a significant population of both L and T dwarfs which are red or potentially "ultra-cloudy" compared to the models, many of which are known to be young indicating a correlation between enhanced photospheric dust and youth. For the low surface gravity or young companion L dwarfs we find that 8 out of 10 are at least [0.2-1.0] mag underluminous in M_JH_and/or M_K_compared to equivalent spectral type objects. We speculate that this is a consequence of increased dust opacity and conclude that low surface gravity L dwarfs require a completely new spectral-type/absolute magnitude polynomial for analysis.
78. Belgrade meridian circle catalog
ID:
ivo://CDS.VizieR/J/other/BOBeo/155.3
Title:
Belgrade meridian circle catalog
Short Name:
J/other/BOBeo/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
The authors present an observational catalogue containing the positions of 351 stars situated in the vicinity of radio sources (RRS2, Tel'nyuk-Adamchuk & Kumkova, 1991, IAU Colloq. 127, 363) worked out by differential method in the FK5 system. The (O-C) corrections to the positions of 267 fundamental stars used in the determination of the instrument parameters are also presented. The star positions are derived from the observations with the Belgrade Large Meridian Circle during 1991-1993.
79. BeppoSAX/GRBM {gamma}-ray Burst Catalog
ID:
ivo://CDS.VizieR/J/ApJS/180/192
Title:
BeppoSAX/GRBM {gamma}-ray Burst Catalog
Short Name:
J/ApJS/180/192
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the catalog of Gamma-Ray Bursts (GRBs) detected with the Gamma Ray Burst Monitor aboard the BeppoSAX satellite. It includes 1082 GRBs with 40-700keV fluences in the range from 1.3x10-7 to 4.5x10-4erg/cm^2^, and 40-700keV peak fluxes from 3.7x10-8 to 7.0x10-5erg/cm^2^/s. We report in the catalog some relevant parameters of each GRB.
80. Bessel (1825) calculation for geodesic measurements
ID:
ivo://CDS.VizieR/J/AN/331/852
Title:
Bessel (1825) calculation for geodesic measurements
Short Name:
J/AN/331/852
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is an English translation of F.W. Bessel's paper on geodesics which appeared as "Ueber die Berechnung der geographischen Laengen und Breiten aus geodaetischen Vermessungen", Astronomische Nachrichten 4(86), 241-254 (1825), 1825AN......4..241B.

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