Related papers: Validation of the new Hipparcos reduction
A subset of 51 Hipparcos astrometric binaries among FG dwarfs within 67pc has been surveyed with the NICI adaptive optics system at Gemini-S, directly resolving for the first time 17 sub-arcsecond companions and 7 wider ones. Using these…
As of 2012 Jan 21, the Pan-STARRS 1 3\pi Survey has observed the 3/4 of the sky visible from Hawaii with a minimum of 2 and mean of 7.6 observations in 5 filters, g_p1, r_p1, i_p1, z_p1, y_p1. Now at the end of the second year of the…
Tycho Brahe completed his catalogue with the positions and magnitudes of 1004 fixed stars in 1598. This catalogue circulated in manuscript form. Brahe edited a shorter version with 777 stars, printed in 1602, and Kepler edited the full…
Kepler provides light curves of 156,000 stars with unprecedented precision. However, the raw data as they come from the spacecraft contain significant systematic and stochastic errors. These errors, which include discontinuities, systematic…
Stellar spectropolarimetry is a relatively new remote sensing tool for exploring stellar atmospheres and circumstellar environments. We present the results of our HiVIS survey and a multi-wavelength ESPaDOnS follow-up campaign showing…
Three binary systems in the Hyades open cluster (51 Tau, V818 Tau, and $\theta^2$ Tau}, with known metallicity and good Johnson photometric data are used to test the validity of three independent sets of stellar evolutionary tracks. A…
We describe the astrometric reduction of images obtained with the FORS2/VLT camera in the framework of an astrometric planet search around 20 M/L-transition dwarfs. We present the correction of systematic errors, the achieved astrometric…
Major advancements in space science and detector technology brought about a revolution in global astrometry, the science of measuring distances and motions of stars in the Milky Way and in the local universe. From the first ESA astrometric…
We consider the problem of determining the Galaxy's gravitational potential from a star catalogue. We show that orbit-based approaches to this problem suffer from unacceptable numerical noise deriving from the use of only a finite number of…
We present an improved data-reduction technique to obtain high-precision proper motions (PMs) of globular clusters using Hubble Space Telescope data. The new reduction is superior to the one presented in the first paper of this series for…
We have used main-sequence fitting to calibrate the distances to the globular clusters NGC 6397, M5, NGC 288, M71 and 47 Tucanae, matching the cluster photometry against data for subdwarfs with precise Hipparcos parallax measurements and…
Proper motions are computed and collected in a catalog using the Hipparcos positions (epoch 1991.25) and URAT1 positions (epoch 2012.3 to 2014.6). The goal is to obtain a significant improvement on the proper motion accuracy of single stars…
The third Gaia data release is published in two stages. The early part, Gaia EDR3, gives very precise astrometric and photometric properties for nearly two billion sources together with seven million radial velocities from Gaia DR2. The…
Accurate measurement of pulsar distances via astrometry using very long baseline interferometry enables the improvement of Galactic electron density distribution models, improving distance estimates for the vast majority of pulsars for…
We present the results of applying automated machine learning techniques to the problem of matching different object catalogues in astrophysics. In this study we take two partially matched catalogues where one of the two catalogues has a…
Astrometric measurements for 25 red dwarf systems are presented, including the first definitive trigonometric parallaxes for 20 systems within 10 pc of the Sun, the horizon of the RECONS sample. The three nearest systems that had no…
We outline the construction of an updated version of the New Luyten Two-Tenths (NLTT) catalog of high proper motion stars, which will contain improved astrometry and photometry for the vast majority of the ~59,000 stars in NLTT. The bright…
[abridged] We attempt to improve on the characterization of the properties (orbital elements, masses) of two Doppler-detected sub-stellar companions to the nearby G dwarfs HD 131664 and HD 43848. We carry out orbital fits to the Hipparcos…
Aims: Accurate astrometry is required to reliably cross-match 20th-century catalogues against 21st-century surveys. The present work aims to provide such astrometry for the 625 entries of the Bohannan & Epps (BE74) catalogue of H$\alpha$…
In this work we study in details the influence of pure astronomical refraction on solar metrologic measurements made from ground-based full disk imagery and provide the tools for correcting the measurements and estimating the associated…