Galactic cirrus emission at far-infrared wavelengths affects many extragalactic observations. Separating this emission from that associated with extragalactic objects is both important and difficult. In this paper we discuss a particular case, the M81 group, and the identification of diffuse structures prominent in the infrared, but also detected

We present results of numerical 3D simulation of propagation of MHD waves in sunspots. We used two self consistent magnetohydrostatic background models of sunspots. There are two main differences between these models: (i) the topology of the magnetic field and (ii) dependence of the horizontal profile of the sound speed on depth. The model with

The main goal of this thesis work is to find the links between star formation in galaxy bulges (mainly in the form of star-forming nuclear rings) and other properties of the host galaxy, such as the bar strength or the presence of sigma-drops. To do so we study galaxy non-axisymmetries and their side effects, such as dust lanes in bars. At the end

We have been monitoring the position of the very faint X-ray transient XTE J1728-295 (= IGR J17285-2922, ATel #2823, #2824, #2825) with the Faulkes Telescopes North and South throughout its outburst. Data were acquired on thirteen dates from 1st September until 28th October, mostly in I- band and R-band. Of the original seven stars detected with

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear