The spectrum of O and B Supergiants is known to be affected by an important extra line-broadening (usually called macroturbulence) that adds to stellar rotation. Recent analysis of high resolution spectra has shown that the interpretation of this line-broadening as a consequence of large-scale turbulent motions would imply highly super-sonic

A list of 199 standard stars suitable for the ESO standard photometric system at JHKLM is given. Faint stars (although brighter than K = 7.7) to be used on larger telescopes are included. This list is based on an analysis of all infrared photometric observations carried out at La Silla from 1979 until 1989 inclusive. The accuracy of the data (about

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Aims: Planets in the mass range from 2 to 15 M⊕ are very diverse. Some of them have low densities, while others are very dense. By measuring the masses and radii, the mean densities, structure, and composition of the planets are constrained. These parameters also give us important information about their formation and evolution, and about possible

We have obtained spectra with the 10-m Keck telescope of a sample of 24 galaxies having colors consistent with star-forming galaxies at redshifts 2 ≲ z ≲ 4.5 in the Hubble Deep Field (HDF). Eleven of these galaxies are confirmed to be at high redshift (zmed=3.0). The spectra of the confirmed high-redshift galaxies show a diversity of features

Through the observational study of stellar pulsations, the internal structure of stars can be probed and theoretical models can be tested. The main sequence γ Doradus (Dor) and δ Scuti (Sct) stars with masses 1.2-2.5 M&sun; are particularly interesting for asteroseismic study. The γ Dor stars pulsate in high-order gravity (g) modes, with