Astrometry ≈ Astrometry
View article: <i>Gaia</i> Data Release 2
<i>Gaia</i> Data Release 2 Open
Context. Gaia Data Release 2 ( Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by the European Space Agency Gaia satellite during the first 22 months of its operational pha…
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<i>Gaia</i>Early Data Release 3 Open
Context. Gaia Early Data Release 3 ( Gaia EDR3) contains results for 1.812 billion sources in the magnitude range G = 3–21 based on observations collected by the European Space Agency Gaia satellite during the first 34 months of its operat…
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Gaia Data Release 1 Open
Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presente…
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Gaia Data Release 2: The astrometric solution Open
Gaia Data Release 2 (Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by the European Space Agency Gaia satellite during the first 22 months of its operational phase. We des…
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<i>Gaia</i> Data Release 2 Open
Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry and photometry are unprecedented. Aims. …
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<i>Gaia</i>Early Data Release 3 Open
Context. Gaia Early Data Release 3 ( Gaia EDR3) contains astrometry and photometry results for about 1.8 billion sources based on observations collected by the European Space Agency Gaia satellite during the first 34 months of its operatio…
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ASTROIMAGEJ: IMAGE PROCESSING AND PHOTOMETRIC EXTRACTION FOR ULTRA-PRECISE ASTRONOMICAL LIGHT CURVES Open
ImageJ is a graphical user interface (GUI) driven, public domain, Java-based, software package for general image processing traditionally used mainly in life sciences fields. The image processing capabilities of ImageJ are useful and exten…
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Gaia Early Data Release 3: Summary of the contents and survey properties Open
CONTEXT: We present the early installment of the third Gaia data release, Gaia EDR3, consisting of astrometry and photometry for 1.8 billion sources brighter than magnitude 21, complemented with the list of radial velocities from Gaia DR2.…
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<i>Gaia</i> Data Release 2 Open
Context. The second Gaia data release (DR2) contains very precise astrometric and photometric properties for more than one billion sources, astrophysical parameters for dozens of millions, radial velocities for millions, variability inform…
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<i>Gaia</i>Data Release 1 Open
Gaia Data Release 1 (Gaia DR1) contains astrometric results for more than 1 billion stars brighter than magnitude 20.7 based on observations collected by the Gaia satellite during the first 14 months of its operational phase. We give a bri…
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First light for GRAVITY: Phase referencing optical interferometry for the Very Large Telescope Interferometer Open
GRAVITY is a new instrument to coherently combine the light of the European Southern Observatory Very Large Telescope Interferometer to form a telescope with an equivalent 130 m diameter angular resolution and a collecting area of 200 m 2 …
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The GALAH+ survey: Third data release Open
The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the Milky Way. With this third data release of the Galactic Ar…
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New Parallaxes of Galactic Cepheids from Spatially Scanning the Hubble Space Telescope: Implications for the Hubble Constant Open
We present new measurements of the parallax of seven long-period (≥10 days) Milky Way (MW) Cepheid variables (SS CMa, XY Car, VY Car, VX Per, WZ Sgr, X Pup, and S Vul) using one-dimensional astrometric measurements from spatial scanning of…
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Painting a portrait of the Galactic disc with its stellar clusters Open
Context. The large astrometric and photometric survey performed by the Gaia mission allows for a panoptic view of the Galactic disc and its stellar cluster population. Hundreds of stellar clusters were only discovered after the latest Gaia…
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The LCES HIRES/Keck Precision Radial Velocity Exoplanet Survey Open
We describe a 20 year survey carried out by the Lick-Carnegie Exoplanet Survey Team (LCES), using precision radial velocities from HIRES on the Keck I telescope to find and characterize extrasolar planetary systems orbiting nearby F, G, K,…
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Detection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole Open
The star S2 orbiting the compact radio source Sgr A* is a precision probe of the gravitational field around the closest massive black hole (candidate). Over the last 2.7 decades we have monitored the star’s radial velocity and motion on th…
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<i>Gaia</i> Data Release 2 Open
The second Gaia data release ( Gaia DR2) contains, beyond the astrometry, three-band photometry for 1.38 billion sources. One band is the G band, the other two were obtained by integrating the Gaia prism spectra (BP and RP). We have used t…
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The JPL Planetary and Lunar Ephemerides DE440 and DE441 Open
The planetary and lunar ephemerides called DE440 and DE441 have been generated by fitting numerically integrated orbits to ground-based and space-based observations. Compared to the previous general-purpose ephemerides DE430, seven years o…
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Gaia EDR3 view on galactic globular clusters Open
We use the data from Gaia Early Data Release 3 (EDR3) to study the kinematic properties of Milky Way globular clusters. We measure the mean parallaxes and proper motions (PM) for 170 clusters, determine the PM dispersion profiles for more …
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A million binaries from <i>Gaia</i> eDR3: sample selection and validation of <i>Gaia</i> parallax uncertainties Open
We construct from Gaia eDR3 an extensive catalogue of spatially resolved binary stars within ≈1 kpc of the Sun, with projected separations ranging from a few au to 1 pc. We estimate the probability that each pair is a chance alignment empi…
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Gaia Data Release 1: Astrometry - one billion positions, two million proper motions and parallaxes Open
Gaia Data Release 1 (Gaia DR1) contains astrometric results for more than 1 billion stars brighter than magnitude 20.7 based on observations collected by the Gaia satellite during the first 14 months of its operational phase. We give a bri…
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<i>Gaia</i>Early Data Release 3 Open
Context. 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 DR…
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Stellar and substellar companions of nearby stars from <i>Gaia</i> DR2 Open
Context . The census of stellar and substellar companions of nearby stars is largely incomplete, in particular toward the low-mass brown dwarf and long-period exoplanets. It is, however, fundamentally important in the understanding of the …
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Unresolved stellar companions with <i>Gaia</i> DR2 astrometry Open
For stars with unresolved companions, motions of the centre of light and that of mass decouple, causing a single-source astrometric model to perform poorly. We show that such stars can be easily detected with the reduced χ2 statistic, or r…
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The VLA-COSMOS 3 GHz Large Project: Continuum data and source catalog release Open
We present the VLA-COSMOS 3 GHz Large Project based on 384 hours of\nobservations with the Karl G. Jansky Very Large Array (VLA) at 3 GHz (10 cm)\ntoward the two square degree Cosmic Evolution Survey (COSMOS) field. The final\nmosaic reach…
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The MUSE <i>Hubble </i>Ultra Deep Field Survey Open
We present the MUSE Hubble Ultra Deep Survey, a mosaic of nine MUSE fields covering 90% of the entire HUDF region with a 10-h deep exposure time, plus a deeper 31-h exposure in a single 1.15 arcmin 2 field. The improved observing strategy …
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<i>Gaia</i>Data Release 3 Open
Context. Gaia Data Release 3 ( Gaia DR3) contains the second release of the combined radial velocities. It is based on the spectra collected during the first 34 months of the nominal mission. The longer time baseline and the improvements o…
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Gaia Data Release 2. Observational Hertzsprung-Russell diagrams Open
[Abstract] Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry and photometry are unpreceden…
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Pan-STARRS Photometric and Astrometric Calibration Open
We present the details of the photometric and astrometric calibration of the Pan-STARRS1 3 π Survey. The photometric goals were to reduce the systematic effects introduced by the camera and detectors, and to place all of the observations o…
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The Sirius System and Its Astrophysical Puzzles: Hubble Space Telescope and Ground-based Astrometry<sup>∗</sup> Open
Sirius, the seventh-nearest stellar system, is a visual binary containing the metallic-line A1 V star Sirius A, the brightest star in the sky, orbited in a 50.13 year period by Sirius B, the brightest and nearest white dwarf (WD). Using im…