Context. This is the second paper of a series on Galactic OB groups that uses astrometric
and photometric data from Gaia and spectral classifications from the Galactic O-Star …

Context. The spectral classifications of the Galactic O-Star Spectroscopic Survey (GOSSS)
and the astrometric and photometric data from Gaia have significantly improved our ability to …

The Galactic O star catalog (GOS) is an ambitious project to provide as much information
regarding these types of objects as possible. The first version of the catalog (GOS v1) …

This is the third installment of the Galactic O-Star Spectroscopic Survey (GOSSS), a massive
spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise …

Context. The apparent lack of massive O-type stars near the zero-age main sequence, or
ZAMS (at ages< 2 Myr), is a topic that has been widely discussed in the past 40 yr. Different …

We present the second installment of GOSSS, a massive spectroscopic survey of Galactic O
stars, based on new homogeneous, high signal-to-noise ratio, R∼ 2500 digital observations …

For application to surveys of interstellar matter and Galactic structure, we compute new
spectrophotometric distances to 139 OB stars frequently used as background targets for UV …

We present the first installment of a massive spectroscopic survey of Galactic O stars, based
on new, high signal-to-noise ratio, R∼ 2500 digital observations from both hemispheres …

Context. The young massive cluster Westerlund 1 offers the promise of a grand laboratory
for the study of high-mass star evolution, but its basic parameters are still poorly known …

The IACOB spectroscopic survey of Galactic OB stars is an ambitious observational project
aimed at compiling a large, homogeneous, high-resolution database of optical spectra of …