Related papers: Overall properties of the Gaia DR1 reference frame
Galactic aberration (GA) is a small effect in proper motions of celestial objects with an amplitude of about 5 $\mu$as/yr already noticeable in highly accurate astrometric observations such as VLBI and Gaia. However accurate accounting for…
CONTEXT. The Gaia Collaboration has used Gaia-DR2 sources with six-dimensional (6D) phase space information to derive kinematical maps within 5 kpc of the Sun, which is a reachable range for stars with relative error in distance lower than…
We use the Gaia DR2 catalog to improve the astrometric accuracy of about 1.7 billion objects in Pan-STARRS1 Data Release 2 (PS1 DR2). We also obtain proper motions for these PS1 objects. The cross match between Gaia and PS1 reveals…
We employ the earlier published proper motions of the newly discovered Antlia 2 dwarf galaxy derived from Gaia data to calculate its orbital distribution in the cosmologically recent past. Using these observationally motivated orbits, we…
We have analyzed the differences in positions of 9081 matched sources between the Gaia DR2 and VLBI catalogues. The median position uncertainty of matched sources in the VLBI catalogue is a factor of two larger than the median position…
We present a comprehensive analysis of the multi-phase structure of the interstellar medium (ISM) and the stellar kinematics in the edge-on nearby galaxy UGC 10205 using integral field spectroscopy (IFS) data taken with MEGARA at the GTC.…
We compared positions of the Gaia first data release (DR1) secondary data set at its faint limit with CCD positions of stars in 20 fields observed with the VLT/FORS2 camera. The FORS2 position uncertainties are smaller than one…
Context. It will soon become possible to directly link the most accurate radio reference frame with the Gaia optical reference frame using many common extragalactic objects. It is important to know the level of coincidence between the radio…
We have analyzed the kinematics of OB2 stars with proper motions and parallaxes selected by Xu et al. from the Gaia EDR3 catalog. The relative parallax errors for all the stars in this sample do not exceed 10\%. Based on a sample of 9750…
Hidden within the Gaia satellite's multiple data releases lies a valuable cache of dark companions. To facilitate the efficient and reliable detection of these companions via combined analyses involving Gaia, Hipparcos, and Tycho-2…
We perform a kinematic analysis of the Hipparcos and TRC proper motions of stars by using a linear Ogorodnikov-Milne model. All of the distant (r more than 0.2 kpc) stars of the Hipparcos catalog have been found to rotate around the…
We present an independent confirmation of the zero-point offset of ${\rm \it Gaia}$ Data Release 2 (DR2) parallaxes using asteroseismic data of evolved stars in the ${\rm \it Kepler}$ field. Using well-characterized red giant branch (RGB)…
We employ differential astrometric methods to establish a small field reference frame stable at the micro-arcsecond ($\mu$as) level on short timescales using high-cadence simulated observations taken by Gaia in February 2017 of a bright…
The primary sample of the {\it Gaia} Data Release 1 is the Tycho-Gaia Astrometric Solution (TGAS): $\approx$ 2 million Tycho-2 sources with improved parallaxes and proper motions relative to the initial catalog. This increased astrometric…
We present observations of 50 pairs of redshift z ~ 0.2 star-forming galaxies and background quasars. These sightlines probe the circumgalactic medium (CGM) out to half the virial radius, and we describe the circumgalactic gas kinematics…
Owing to their shallow stellar potential, dwarf galaxies possess thick gas disks, which makes them good candidates for studies of the galactic vertical kinematical structure. We present 21 cm line observations of the isolated nearby dwarf…
Isolated galaxies are rare yet invaluable for studying secular evolution, as their physical properties can remain largely unaffected by external influences for several billion years, primarily shaped by internal evolutionary processes. This…
This paper presents a cross-calibrated catalog of Hipparcos and Gaia astrometry to enable their use in measuring changes in proper motion, i.e., accelerations in the plane of the sky. The final catalog adopts the reference frame of the…
We compare dynamical mass estimates based on spatially extended stellar and ionized gas kinematics ($\mathrm{M_{dyn,*}}$ and $\mathrm{M_{dyn,eml}}$, respectively) of 157 star forming galaxies at $0.6\leq z<1$. Compared to $z\sim0$, these…
We used 1,477,047 data from DR1-TGAS, in order to analyse the minimum require- ments of accuracy, necessary to detect sub-stellar objects in the astrometric mea- surements of Gaia. We found that the first set of data (DR1) does not have…