We present the discovery of SDSS J135154.46-064309.0, a short-period variable observed using 30-mincadence photometry in K2 Campaign 6. Follow-up spectroscopy and high-speed photometry support a classification as a new member of the rare class of ultracompact accreting binaries known as AM CVn stars. The spectroscopic orbital period of 15.65 ± 0.12

We present a three dimensional velocity analysis of Milky Way disc kinematics using LAMOST K giant stars and the GPS1 proper motion catalogue. We find that Galactic disc stars near the anticentre direction (in the range of Galactocentric distance between R = 8 and 13 kpc and vertical position between Z = -2 and 2 kpc) exhibit asymmetrical motions

A bewildering variety of eruptive and ejective phenomena continually take place in the solar atmosphere on a wide range of space and time scales. Particular attention was devoted in the past decades to those associated with the reconnection of magnetic field lines of separate plasma systems that come into contact in the atmosphere, especially when

We present the Oscillating Stars with wIneRed near-Infrared Spectroscopy (OSIRIS) project, aimed at deriving accurate chemical abundances of primary distance indicators covering a wide age range from young Classical Cepheids to intermediate-age Anomalous Cepheids and Miras, old RR Lyrae stars, and Type-II Cepheids. High-resolution near-infrared

The James Webb Space Telescope offers astronomers the opportunity to observe the composition, structure, and dynamics of transiting exoplanet atmospheres with unprecedented detail. However, such observations require very precise time-series spectroscopic monitoring of bright stars and present unique technical challenges. The Transiting Exoplanet

This paper is the first in a series of two that deals with the physical and numerical grounds of stellar atmospheres modelling. After a phenomenological definition of a star and a stellar atmosphere, the physics that shapes the stellar atmosphere physical system is discussed and three alternative pictures are considered for its representation.