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- ID:
- ivo://CDS.VizieR/I/57
- Title:
- Abbadia Catalogue of 14263 Stars, +16 to +24{deg}
- Short Name:
- I/57
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains meridian circle observations of 14192 reference stars in the Paris Observatory zone of the Astrographic Catalog, +16 to +24deg, made from 1899 to 1906. The original catalog contains also a supplement of 81 stars, which is not included here. The positions have been reduced to 1900.0 on the basis of Newcomb's constants. The probable errors for most stars range from 0.0093s to 0.0161s in right ascension and from 0.096" to 0.162" in declination, depending on the number of observations. In addition to the positions, the catalog contains a running number, the magnitude from the Berlin catalogs, the mean epoch and number of observations, and the BD number.
- ID:
- ivo://CDS.VizieR/I/331
- Title:
- Absolute Proper motions Outside the Plane (APOP)
- Short Name:
- I/331
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of absolute proper motions and updated positions derived from the same Space Telescope Science Institute digitized Schmidt survey plates utilized for the construction of the Guide Star Catalog II. As special attention was devoted to the absolutization process and removal of position, magnitude and color dependent systematic errors through the use of both stars and galaxies, this release is solely based on plate data outside the galactic plane, i.e. |b|>=27{deg}. The resulting global zero point error is less than 0.6 mas/yr, and the precision better than 4.0mas/yr for objects brighter than R_F_=18.5, rising to 9.0mas/yr for objects with magnitude in the range 18.5<R_F_<20.0. The catalog covers 22,525 square degrees and lists 100,774,153 objects to the limiting magnitude of R_F_~20.8. Alignment with the International Celestial Reference System (ICRS) was made using 1288 objects common to the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths. As a result, the coordinate axes realized by our astrometric data are believed to be aligned with the extragalactic radio frame to within +/-0.2mas at the reference epoch J2000.0. This makes our compilation one of the deepest and densest ICRF-registered astrometric catalogs outside the galactic plane. Although the Gaia mission is poised to set the new standard in catalog astronomy and will in many ways supersede this catalog, the methods and procedures reported here will prove useful to remove astrometric magnitude- and color-dependent systematic errors from the next generation of ground-based surveys reaching significantly deeper than the Gaia catalog.
- ID:
- ivo://CDS.VizieR/J/AN/323/484
- Title:
- Accurate coordinates of Planetary Nebulae
- Short Name:
- J/AN/323/484
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate optical coordinates of 734 PNe, measured on the charts of the Digitized Palomar Sky Survey (DSS-2), are presented. As a result of the discussion about the external accuracy the constants -0.8" in RA and +0.8" in DEC should be added to the coordinates measured by us. They were used but rounded off already in CGPN(2000).
- ID:
- ivo://CDS.VizieR/J/A+AS/144/475
- Title:
- Accurate positions for 17124 galaxies
- Short Name:
- J/A+AS/144/475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper gives accurate coordinates and diameters for 3301 galaxies, companions of UGC galaxies. (about 2764 companions were not yet available in electronic form). In addition previously poor equatorial coordinates are re-measured for 13823 galaxies. These coordinates which have an accuracy of 5'' or better will be used for facilitating the cross-identification with forthcoming catalogues of millions of galaxies.
- ID:
- ivo://CDS.VizieR/J/PASP/110/779
- Title:
- Accurate Positions for MCG Galaxies
- Short Name:
- J/PASP/110/779
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured accurate celestial coordinates for over 4000 extragalactic objects primarily drawn from a list of MCG galaxies with no recently published accurate positions. We used IPAC's Skyview program to display FITS images clipped from the Digitized Sky Survey, and to measure the coordinates. The standard deviations in the new positions depend slightly on the measurement command used, but are on the order of 1.0 arcsec to 1.2 arcsec (internal errors). The table of data includes all the duplicate measurements we made, as well as corrections and additions made after the PASP paper was submitted, so has 5120 entries.
- ID:
- ivo://CDS.VizieR/J/A+AS/147/169
- Title:
- Accurate positions of 2978 SBS objects
- Short Name:
- J/A+AS/147/169
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical positions of 2978 objects listed in the Second Byurakan Survey (SBS) were obtained using the Digitized Sky Survey (DSS), and are given with an rms un certainty ~1 arcsec in each coordinate.
- ID:
- ivo://CDS.VizieR/J/A+AS/64/247
- Title:
- Accurate positions of Zwicky galaxies
- Short Name:
- J/A+AS/64/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate optical positions are given for 1007 galaxies in the Zwicky Catalogue fields 502-505, 519-523, 536-539.
- ID:
- ivo://CDS.VizieR/J/MNRAS/442/2240
- Title:
- Accurate water maser positions from HOPS
- Short Name:
- J/MNRAS/442/2240
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on high spatial resolution water maser observations, using the Australia Telescope Compact Array, towards water maser sites previously identified in the H2O southern Galactic Plane Survey (HOPS) within the area covering Galactic coordinates from l=290 to l=30 and b=-0.5 to b=+0.5. Of the 540 maser sites identified in the single-dish observations of Walsh et al. (2011MNRAS.416.1764W, Cat. J/MNRAS/416/1764), we detect emission in all but 31 fields. These maser sites together comprise 2790 individual spectral features (maser spots), with brightnesses ranging from 0.06Jy to 576Jy and with velocities ranging from -238.5 to +300.5km/s. Based on a definition of maser site size of 4-arcsec (except for G000.667+0.028, also known as Sgr B2, which we treat as a special case), we identify 631 maser sites. We have compared the positions of these sites to the literature to associate the sites with astrophysical objects. We identify 433 (69%) with star formation, 121 (19%) with evolved stars and 77 (12%) as unknown. Comparing the properties of maser sites of different origins, we find that those associated with evolved stars tend to have more maser spots and have smaller angular sizes than those associated with star formation. We present evidence that maser sites associated with evolved stars show an increased likelihood of having a velocity range between 15 and 35 km/s compared to other maser sites. We suggest this is because many of these maser sites are associated with the circumstellar shells of the evolved stars, which are expanding at these velocities. Of the 31 non-detections, we conclude they were not detected due to intrinsic variability and confirm previous results showing that such variable masers tend to be weaker and have simpler spectra with fewer peaks. Of the small number of maser sites showing linear features, we find evidence for lines that are both perpendicular and parallel to known outflows, suggesting that in star formation, H_2_O maser origins may be as varied and as complex as those of class II methanol masers.
- ID:
- ivo://CDS.VizieR/J/MNRAS/505/5253
- Title:
- A comparison of centering in ISS astrometry
- Short Name:
- J/MNRAS/505/5253
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- In the caviar software package, a standard tool for astrometry of images from the Cassini imaging science subsystem (ISS), Gaussian fitting is used to measure the centre of point-like objects, achieving a typical precision of about 0.2 pixels. In this work, we consider how alternative methods may improve on this. We compare three traditional centroiding methods: two-dimensional Gaussian fitting, median, and modified moment. Results using 56 selected images show that the centroiding precision of the modified moment method is significantly better than the other two methods, with standard deviations for all residuals in sample and line of 0.065 and 0.063 pixels, respectively, representing a factor of over 2 improvement compared to Gaussian fitting. Secondly, a comparison of observations using Cassini ISS images of Anthe is performed. Anthe results show a similar improvement. The modified moment method is then used to reduce all ISS images of Anthe during the period 2008-2017. The observed-minus-calculated residuals relative to the JPL SAT393 ephemeris are calculated. In terms of {alpha}xcos({delta}) and {delta} in the Cassini-centred international celestial reference frame, mean values of all residuals are close to 0km, and their standard deviations are less than 1km for narrow angle camera images, and about 4km for wide angle camera images.
