514 datasets found

The morphology and kinematics of the spiral structure of the Milky Way are long-standing problems in astrophysics. In this review we firstly summarize various methods with...

The precise positions and proper motions (J2000.0) of 1535 Basic FK5 (FK4) stars in FK5 system (Cat. ) have been used in the reduction of local vertical monitoring and catalog...

In this paper, relation was established for Hyades stars between their apparent magnitudes and parallaxes. The precision criteria of this relation are very satisfactory. The...

The nature and origin of free-floating planets (FFPs) are still largely unconstrained because of a lack of large homogeneous samples to enable a statistical analysis of their...

The Milky Way's neutral hydrogen (HI) disk is warped and flared. However, a dearth of accurate HI-based distances has thus far prevented the development of an accurate Galactic...

The author describes the discovery of 4 new pairs of stars with almost identical proper motions and parallaxes (from Gaia DR2 data). Cone search capability for table...

The establishment of new spectral classes cooler than type M has had a brief, yet already rich, history. Prototypes of the new "L dwarf" and "T dwarf" classes were first found...

OB stars are crucial for our understanding of Galactic structure, star formation, stellar feedback and multiplicity. In this paper we have compiled a census of all OB stars...

Stellar multiplicity is a key aspect of exoplanet diversity, as the presence of more than one star in a planetary system can have both devastating and positive effects on its...

Studies of solar twins have key impacts on the astronomical community, but only ~100-200 nearby solar twins (<1 kpc) have been reliably identified over the last few decades....

A total of 3350 objects from the Sixth Catalog of Orbits of Visual Binary Stars (ORB6) are investigated to validate Gaia Early Data Release 3 (EDR3) parallaxes and provide mass...

This paper presents the first census of Galactic post-asymptotic Giant Branch stars in the HR diagram. We combined Gaia DR3 parallax-based distances with extinction corrected...

Westerlund 1 (Wd 1) is one of the most massive young star clusters in the Milky Way. Although relevant for star formation and evolution, its fundamental parameters are not yet...

The proper motions (PMs) of OB stars in Cygnus have recently been found to exhibit two large-scale kinematic patterns suggestive of expansion. We perform a 3D traceback on these...

Massive O and early B stars are important markers of recent star formation and exert a significant influence on their environments during their short lives via photoionization...

We present an astrometric and photometric wide-field study of the Galactic open star cluster M37 (NGC 2099). The studied field was observed with ground-based images covering a...

Ultra-short orbital period contact binaries (P_orb_ < 0.26 d) host some of the smallest and least massive stars. These systems are faint and rare, and it is believed that...

The gravitational redshift induced by stellar surface gravity is notoriously difficult to measure for non-degenerate stars, since its amplitude is small in comparison with the...

We present new luminosity-metallicity (LZ ; M_V_-[Fe/H] and M_G_-[Fe/H]) and relations and, for the first time, empirical, Gaia three-band (G, G_BP_, G_RP_)...

We present the results of the investigation of 58 open clusters using UBVRI CCD photometry (Johnsons-Cousins system) and Gaia eDR3 data. The membership probability of the stars...