Old galaxies in the aging universe (Free Astronomy Public Lectures)

Presented by Pierluigi Cerulo and Nicola Pastorello on 15th February 2013.As part of a 14 billion years old expanding universe, we are able to directly experience only a tiny part of its history. In order to reconstruct the evolutionary history of the universe, it is fundamental to study the properties of objects which are billions of light years away from us. In fact, the light coming from these galaxies travels at a finite speed, giving us a picture of how they were when the universe was much younger. However galaxies are complex systems that evolve as they form new stars and interact with each other. As galaxies become old they acquire an apparently featureless elliptical morphology that, despite its structural simplicity, encloses all the complexities involved in galaxy evolution. Likewise a collection of family portraits that tells about the human society at the time when the pictures were taken, the observation and the subsequent comparison of nearby and distant elliptical galaxies allow us to reconstruct the evolution of the universe. In this talk we will present some results from the ongoing research conducted at Swinburne on nearby and distant galaxies with the most powerful currently available telescopes such as Keck, Gemini and Hubble.