The Deep Near-Infrared Survey (DENIS) project is the first attempt to carry out a complete digitized survey of the southern sky in the range 1-2.5 micrometers. The main objectives of the program and the main specifications of the camera and of the data processing stream are briefly outlined.

The implicit intergral method that we have already introduced in a previous paper, together with its application to the non-Local Thermal Equilibrium (non-LTE) line formation problem, is considered here for another paradigm problem, namely, the self-consistent temperature correction when computing Local Thermal Equilibrium (LTE) stellar atmosphere

We report on the serendipitous discovery of a Herbig-Haro flow close to the pre-main sequence system HV Tauri. Low resolution spectra indicate a high excitation flow. The profile of emission lines seen at high resolution shows the existence of two velocity components, which are interpreted as emission from a bow shock directed towards the observer

β1 Monocerotis is a Be star with a V/R cycle of 12.5 years. We observed the star from CTIO (Chile) and with the IUE satellite and found that the star undergoes photospheric oscillations of 1.7 hours and presents a chromospheric structure in the extended atmosphere. Infall velocities and ejection of material are discussed.

We study the behaviour of the interstellar R_n_=n(Zn^+^)/n(Na^0^) ratio in ionization equilibrium conditions. The ratio is very sensitive to variations of the physical state of the gas and is only marginally affected by variations of interstellar depletion. We find logR_n_ {in} [=~-2,=~0] dex in cold molecular clouds, logR_n_ {in} about [0,+1] dex

The vertical stellar distribution of the edge-on spiral NGC 6504 is examined in seven bands (U, B, R, I, J, H, K) by fitting model distributions to the light profile at seven positions along the major axis. In the inner parts of the disk the profile is well approximated by an exponential distribution. At large galactocentric distances, the profile