Women in Physics and Astronomy talk: Duilia de Mello, NASA and Catholic University of America

In this talk I will present the first results of a pilot project named “Deep Images of Mergers” (DIM) aiming at revealing optical shells or ripples around galaxies that might have had a merger with another galaxy in the past. Simulations show that when a large galaxy collides with one 10 or 100 times less massive, it tears the smaller one apart. The stars themselves survive, though, even if their galaxy doesn’t. Their orbits disrupted, they slosh around the larger galaxy, ending up in shells in its periphery. Following the merger, the galaxies are thought to become lenticular, a state of transition between the more typical spiral and elliptical galaxies. To test this idea I have put together a team of 5 Brazilian astrophotographers to take deep images of lenticular galaxies, including Centaurus A and Arp 230. The DIM project is a collaboration currently using a combination of small telescopes across Brazil: two Ritchey-Chretien 8” and 12”, a Celestron 11”, a reflector 450mm and an APM 140 mm refractor. In deep images taken with these relatively small telescopes we are able to see a large field of view and expand our search for faint shells at large distances. After combining all images to the same scale, the first results of the stacked images with dozens of hours of exposure reveal a large number of shells confirming the feasibility of the project and the importance of deep images when analyzing mergers. This project is a type of citizen project that proves that science can be done at home and inspires the population about the importance of science. We are currently recruiting more collaborators to join the DIM network. I will finalize by telling the story of Mulher das Estrelas (Woman of the Stars), its impact in our society and how we can change the world, student by student.