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The X-ray binary system 4U 2206+54 hides many mysteries. Among them, the surprising behavior of both of its co components: the O9.5 dwarf star BD+53°2790 and a slowly rotating neutron star. BD+53°2790 misled the astronomers, exhibiting characteristics reminiscent of Be stars. However, a deeper spectral analysis and more intense monitoring revealed

We present deep Gemini Multi-Object Spectrograph South (GMOS-S)/Gemini optical broad-band images for a complete sample of 46 southern 2 Jy radio galaxies at intermediate redshifts (0.05 z 0.7). Based on them, we discuss the role of galaxy interactions in the triggering of powerful radio galaxies (PRGs). The high-quality observations presented

IPHASX J194359.5+170901 is a new high-excitation planetary nebula with remarkable characteristics. It consists of a knotty ring expanding at a speed of 28 km s-1, and a fast collimated outflow in the form of faint lobes and caps along the direction perpendicular to the ring. The expansion speed of the polar caps is ˜100 km s-1, and their

The investigation of the multiplicity of massive stars is crucial to determine a robust binary fraction but also for understanding the physical properties of these objects. In this contribution, we will present the main results from our long-term spectroscopic survey devoted to the young open cluster NGC 2244. We discuss the spectral classification

In parallel with the monitoring of the periastron passage of the binary system WR 140, a number of B supergiants and Oe stars have been observed in the framework of a 4-month spectroscopic run using the Mons telescope at Teide observatory. We expose the motivations behind this campaign, present an overview of the Hα variations exhibited by the B