We present with outstanding detail an extragalactic perspective of an extended stellar tidal stream wrapping around the edge-on, spiral galaxy NGC 5907. Our deep images reveal for the first time a large scale complex of arcing loops that is an excellent example of how a low-mass satellite accretion can produce a interweaved, rosette-like structure

Seismology of single δ Scuti stars has mainly been inhibited by failing to detect many of the theoretically predicted pulsation modes, resulting in difficulties with mode identification. Theoretical and observational advances have, however, helped to overcome this problem, but the following questions then remain: do we know enough about the star to

Based on spectrophotometric observations from the Guillermo Haro Observatory (Cananea, Mexico), a study of the spectral properties of the complete sample of 24 blue straggler stars (BSs) in the old Galactic open cluster M67 (NGC 2682) is presented. All spectra, calibrated using spectral standards, were recalibrated by means of photometric

The present paper discusses the seismic modelling of five δ Scuti stars belonging to the Praesepe cluster. Linear analysis is confronted with observations, using refined descriptions for the effects of rotation on the determination of the global stellar parameters and on the adiabatic oscillation frequency computations. A single, complete, and

Context: The analysis of unresolved stellar populations demands evolutionary synthesis models with realistic physical ingredients and extended wavelength coverage. Aims: We quantitatively describe the first CO bandhead at 2.3 μm to allow stellar population models to provide improved predictions in this wavelength range. Methods: We observed a new

We measured the stellar kinematics of three face-on galaxies with the aim of searching for box/peanut-shaped (B/P) bulges. These observations test and confirm that face-on B/P bulges can be recognized by two minima in the radial profile of the fourth Gauss-Hermite moment h_4 of the line-of-sight velocity distribution measured along the bar major