Seminars and Colloquia at ESO Santiago

Interactions between radio galaxies and their large-scale environments are key factors to investigate the feedback processes responsible for triggering and fueling AGN activity. To improve our understanding of such interactions, we carried out a multi-frequency analysis based on the comparison of Chandra and VLT/MUSE observations of radio galaxies in the Third Cambridge Catalog. I will focus on the results on 3CR 196.1, the potential first detection of ionized gas filling an X-ray cavity and a prime example of how radio activity can affect the intracluster medium. Lastly, I will present our preliminary results on the optical-to-X-ray comparison of the rest of the sample, which point to a different origin of the ionized gas surrounding radio galaxies as a function of their ionization status. 

Astronomy is one of the most relevant historical activities in Rapa-Nui through centuries. Since many years, archaeoastronomy researches have been made on the whole island, mainly based on the distribution of the moaï, with the conclusions that they clearly show the solstice and equinox directions. Even if the topology of the island has changed through time (construction of the airport, roads etc.), many alignments remain to lead to the conclusion that they were used to fix the annual calendar, with the new year connected to the rising of the Pleiades (Matariki) young open star cluster. Moreover, many petroglyphs and carved flat stones are witnesses of celestial observations (papa uhi etu'u) such as planet movements, comets, novae, supernovae, eclipses etc.