In the race to break the SMC frontier and reach metallicity conditions closer to the First Stars the information from UV spectroscopy is usually overlooked. New HST-COS observations of OB stars in the metal-poor galaxy IC1613, with oxygen content ~1/10 solar, have proved the important role of UV spectroscopy to characterize blue massive stars and

Over the past eight years we have observed optical spectra of planetary nebulae (PNe) in the disk of M31 using DIS on the 3.5-m ARC telescope at Apache Point Observatory and OSIRIS on the 10.4-m GTC on La Palma. We have so far studied more than two dozen objects over a projected galactocentric radius range from 5 - 33 kpc; this corresponds to a

We discuss the role that dwarf galaxies may have played in the formation of the Galactic halo (Halo) using RR Lyrae stars (RRL) as tracers of their ancient stellar component. The comparison is performed using two observables (periods, luminosity amplitudes) that are reddening and distance independent. Fundamental mode RRL in 6 dwarf spheroidals

We present an optical to submillimetre multiwavelength study of two very low-luminosity Class I/flat systems, Mayrit 1701117 and Mayrit 1082188, in the σ Orionis cluster. We performed moderate-resolution (R ˜ 1000) optical (˜0.4-0.9 μm) spectroscopy with the Cassegrain Twin Spectrograph (TWIN) spectrograph at the Calar Alto 3.5-m telescope. The

We present an optical through sub-millimetre multi-wavelength study of two very low-luminosity Class I/Flat systems, Mayrit 1701117 and Mayrit 1082188, in the sigma Orionis cluster. We performed moderate resolution (R 1000) optical ( 0.4-0.9mu) spectroscopy with the TWIN spectrograph at the Calar Alto 3.5-m telescope. The spectra for both sources

The Apache Point Galactic Evolution Experiment (APOGEE) has obtained high resolution (R~22,500) near-infrared spectra of over 100,000 stars, including a subset of ~4000 low-mass dwarfs with estimated effective temperatures of 3500 K Teff 4200 K. We use data from standard stars to confirm the accuracy of APOGEE parameters for these stars, which