相关论文: The Hipparcos Pleiades parallax error is also a pr…
Residuals of a conventional plate adjustment of 5,687 plates of the Second Cape Photographic Catalogue (CPC2) using the Southern Reference Star (SRS) Catalog were analyzed to search for systematic errors depending on the location of the…
Absolute proper motions for $\sim$ 7.7 million objects were derived based on data from the South Galactic Cap u-band Sky Survey (SCUSS) and astrometric data derived from uncompressed Digitized Sky Surveys that the Space Telescope Science…
Using the absolute astrometric positions and proper motions for common stars in the Hipparcos and Gaia catalogs separated by 24.75 years in the mean epoch, we compute mass ratios for long-period, resolved binary systems without any…
We present a proper motion survey of the Galactic plane, using IPHAS data and POSS-I Schmidt plate data as a first epoch, that probes down to proper motions below 50 milliarcseconds per year. The IPHAS survey covers the northern plane ($|b|…
Accelerations of both the solar system barycenter (SSB) and stars in the Milky Way cause a systematic observational effect on the stellar proper motions, which was first studied in the early 1990s and developed by J. Kovalevsky (aberration…
We present radial velocity and new interferometric measurements of the double star Atlas, which permit, with the addition of published interferometric data, to precisely derive the orbital parameters of the binary system and the masses of…
Parallaxes of W UMa stars in the Hipparcos catalogue have been analyzed. 31 W UMa stars, which have the most accurate parallaxes ($\sigma_{\pi}/\pi<0.15$) which are neither associated with a photometric tertiary nor with evidence of a…
We provide a review of the current status of several topics on the ages, distances, and mass functions of open clusters, with a particular emphasis on illuminating the areas of uncertainty. Hipparcos has obtained parallaxes for nearby open…
Context: Stellar clusters are benchmarks for theories of star formation and evolution. The high precision parallax data of the Gaia mission allows significant improvements in the distance determination to stellar clusters and its stars. In…
We present a new method for detecting and correcting systematic errors in the distances to stars when both proper motions and line-of-sight velocities are available. The method, which is applicable for samples of 200 or more stars that have…
Context. The Gaia satellite will measure highly accurate absolute parallaxes of hundreds of millions of stars by comparing the parallactic displacements in the two fields of view of the optical instrument. The requirements on the stability…
Context. The precise determinations of stellar mass at $\sim$1% provide important constraints on stellar evolution models. Accurate parallax measurements can also serve as independent benchmarks for the next Gaia data release. Aims. We aim…
The Hipparcos proper motions of 220 galactic Cepheids, together with relevant ground-based photometry, have been analysed. The effects of galactic rotation are very clearly seen. Mean values of the Oort constants, A = 14.82 +/- 0.84…
We present new spatially resolved astrometry and photometry of the CD-27 11535 system, a member of the $\beta$ Pictoris moving group consisting of two resolved K-type stars on a $\sim$20-year orbit. We fit an orbit to relative astrometry…
I review statistical parallax absolute magnitude determinations which employ data from the HIPPARCOS satellite for RR Lyrae and Cepheid variables, and for several other stellar classes. Five groups have studied the RR Lyrae stars, and the…
Shanks et al. (2018) arXiv:1810.02595 make two claims that they argue bring the local measurement and early Universe prediction of H0 into agreement: A) they claim that Gaia DR2 parallax measurements show the geometric calibration of the…
The GPS1 catalog was released in 2017. It delivered precise proper motions for around 350 million sources across three-fourths of the sky down to a magnitude of $r\sim20$\,mag. In this study, we present GPS1+ the extension GPS1 catalog down…
Previous analyses of various standard candles observed by the Gaia satellite have reported statistically significant systematics in the parallaxes that have improved from $\sim$250 $\mu$as in the first data release (DR1) to 50--80 $\mu$as…
We discuss the different biases affecting the sample of field subdwarfs selected from the Hipparcos Catalogue, and used in the Main Sequence Fitting technique to derive distances to Galactic Globular Clusters. The adopted average…
We have studied the zero-point offset of Gaia early Data Release 3 (EDR3) parallaxes based on a sample of 0.3 million giant stars built from the LAMOST data with distance accuracy better than 8.5\%. The official parallax zero-point…