The Glorious Past of Our Monster Black Hole

Dr. Shuo Zhang, 1:00 – 1:30pm in 37-252

The center of our Galaxy resides a monster black hole, called Sagittarius A* (or Sgr A*), containing 4.5 million times the mass of our sun. While Sgr A* is quite inactive nowadays, there have been abundant observation evidence pointing to a glorious past of this supermassive black hole. Sgr A* has been inferred to produce major outbursts a few hundred years ago, and even more extreme eruptions a few million years ago. What is the physics behind such extreme bahavious of the Galactic center supermassive black hole? Will it become active again in the future? This talk will answer these questions by discussing the past activities and future fate of Sgr A*.

Formation of Gold and other heavy elements via the R(apid neutron capture)-process

Dr. Rana Ezzeddine, 1:30 – 2:00pm in 37-252

Most chemical elements up to Iron are formed in the core of the stars via nucleosynthesis fusion processes of lighter elements into heavier ones. Elements heavier than iron, however, require neutron-capture processes to take place. I will talk about our current understanding of the formation of heavy elements, such as Gold and Uranium, via the (r)apid neutron-capture process within the latest multi-wavelength discovery on 17/08/17 of the neutron star merging event.

How Stars are Born

Dr. Moritz Gunther, 2:00 – 2:30pm in 37-252

While our Sun is almost 5 billion years old, stars still form in the the dark clouds of our Milky Way. When we observe those regions we can learn how star and planet formation works, so that we also understand the formation of our own solar system and the Earth better. I will describe how we observe those regions that are hidden to the naked eye using infrared and X-ray telescopes to obtain stunning images of stellar nurseries. Zooming in on just a few of the young stars, I show how a gas cloud collapses to form a hot gas core that is the birth place of another sun and possibly a few planets. This is the stage of star formation where I concentrate my own research and I will describe how professional astronomers gain access to space telescopes, share my experiences of how to use the Hubble Space Telescope (HST) for my observations of young stars and I will show an example of how we process the observations to extract scientific conclusions. Star formation is a very active area of research with many open questions to solve and certainly one of the areas in astronomy that delivers extremely beautiful images of the Milky Way that surrounds us.

No enrollment limit for talk, no advance sign-up required.