Recent results from Hubble Space Telescope (HST) have resolved starbursts as collections of small young stellar clusters. We have elaborated tep{Melo04} a photometric catalogue of the young stellar clusters in the nuclear starburst of M82, observed with the HST WFPC2 in Hα (F656N) and continuum images. We identify 198 young super stellar clusters

The old stellar populations of the Milky Way carry the signature of their formation environment and dynamical history in their kinematics and chemical abundances. In particular, the dynamically hot thick disk and halo contain the oldest stars in the Galaxy, and are remnants of its more chaotic past. We present a study of the high-latitude thick

We analyze the stellar distribution in the Galactic disc via NIR color-magnitude diagrams (CMDs). Extinction measurements in the K band are also extracted from the diagrams both for supporting stellar counts predictions of the Besançon and "SKY" models and for comparing with a three dimensional model of the Galactic extinction. The method is based

The study of satellite galaxies can provide information on the merging and aggregation processes which, according to the hierarchical clustering models, form the larger spiral galaxies we observe. With the aim of testing hierarchical models of galaxy formation, we have conducted an observational program which comprises H$alpha$ imaging for both the

We present the discovery of a new extreme high proper motion object (˜3.5 arcsec/year) which we classify as an ultracool subdwarf with [M/H] ˜ -0.5. It has a formal spectral type of sdM9 but also shows L-type features: while the VO bands are completely absent, it exhibits extremely strong TiO absorption in its optical spectrum. With a radial

Here we will present some spectroscopic methods for emission gas research in the emission line region of Active Galactic Nuclei (AGNs): (1) We will demonstrate the possibility to use the Boltzmann-plot method to estimate the physical conditions in the broad line regions (BLRs) (2) We will discuss the applicability of so called ``Gaussian method''