Public astronomy lectures presented each month by the Centre for Astrophysics and Supercomputing.
Light is the key piece of the Astrophysics we make today. Thanks to the analysis of the light astronomers know where stars, galaxies are, what they are made of, how they move, and more. I will give some examples of how light is captured and analysed in big telescopes such as the Anglo-Australian Telescope (AAT) of the Australian Astronomical Observatory (AAO), from imaging to spectroscopy, summarising some of its most important scientific results. But I will also talk about how amateur astronomers and citizen scientists are now capturing the light of the Universe, as they are getting astonishing views of the night sky. Deep sky images of both professional and amateur astronomers are inspiring artists and young people in science and technology around the world
Most of the matter in the Universe is dark matter: an elusive particle that is completely invisible. But we can “see” this matter by studying how it distorts the light from galaxies in the distant Universe, a phenomenon called gravitational lensing. I will give a whirlwind tour of gravitational lensing’s “greatest hits” showing how it can be used as a tool to understand some of the most mysterious things in the Universe: from black holes to the “cosmic web” of dark matter that links galaxies together. Presented on 16 March 2018.
Most things in the universe happen over millions or even billions of years but some things change on the timescales of human life and can be seen to change in a matter of months, days, or even seconds. These sources are called transients and are some of the most extreme events in the Universe, things like the collapse of a dying star, or a collision of two massive objects. Humans have been observing astronomical transients for centuries, from supernovae to gamma ray bursts and, most recently, gravitational waves, but recent advances in telescope power and technology mean we’re observing more and more transients each year and even finding new types. In 2007 we discovered a brand new type of transient called fast radio bursts (FRBs), bright radio pulses that last only a few milliseconds. Their origin is one of the newest unsolved mysteries of astronomy but it is clear they are produced in tremendously energetic processes, possibly even billions of light years away. I will tell the story of their discovery, some…
We have been plotting the history of life around the world and climate over more than 1 billion years. Tonight we will zero in on a time when the Earth's first animals came into the picture - at a time when the planet was in the grips of a massive glaciation, Snowball Earth - which is likely better named Slushball Earth. Presented on Friday 7 July 2017.
The whole Universe was in a hot dense state, then nearly 14 billion years ago expansion started. Wait... is the Bang Bang true and how do we know? In this talk Associate Professor Emma Ryan-Weber from the Centre for Astrophysics and Supercomputing will describe the observational evidence for Big Bang Cosmology and how it sets the initial conditions for every atom in the Universe. The talk is especially suitable for year 11 teachers and students studying VCE Physics Unit 1, area of study 3 "What is matter and how is it formed". Presented on 10 February 2017.
Einstein's theory of general relativity predicts that light rays are bent when they travel past a massive object. In this talk, we will explore tests of this prediction and view some of the spectacular consequences of light bending: gravitational lenses. These gravitational lenses let us directly measure where the mass is in the Universe, and the results imply that the Universe is mostly made of an exotic substance called dark matter. Presented on Tuesday 14 November 2017.
Galaxies are the largest structures of matter in our Universe. Our own Milky Way has been studied in glorious detail. We know it has billions of stars, around most of which planets are likely to be found. There is a super massive black hole at its center where anything that gets too close will be consumed. There are intricate dust lanes that obscure the main disk of the galaxy. There is the life-force of stars, hydrogen gas. Finally, there is the mysterious dark matter that acts as a gravitational glue holding the ordinary matter together. But our galaxy is just one of many, and since their discovery, understanding how these complex objects form and evolve has been a focus of astronomers. There are many pathways to reveal more about the nature and evolution of galaxies. In this talk, Dr Rebecca Allen from the Centre for Astrophysics and Supercomputing, will share how she uses the sizes of galaxies to understand more about their growth. Presented on Friday 12 May 2017.
One of the most prominent features of galaxies today is the manifestation of elegant spiral arms. We live in a beautiful grand-design spiral galaxy called the Milky Way. Our Solar System, including the Earth and the only life that we know, lies within the Orion spiral arm of our Milky Way galaxy. However, as we look back in time to the very early Universe, the frequency of spiral galaxies decreases dramatically. In fact, most galaxies in the distant past are messy and irregular in shape. Why is it so? When was the first appearance of spiral arms? How were they formed? In this talk, I will take us 11 billion years back in time through the distorted space surrounding nature's most massive structures. We will get a glimpse of earliest onset of spiral arms and directly witness the formation of a spiral galaxy that could later be home to billions of stars and planets like our earth. Presented on Friday 29 September 2017.
Over the last century, our understanding of the Universe has grown by leaps and bounds whilst posing new questions and testing our very fundamental knowledge and understanding of things around us. To answer these profound questions, scientists are planning ever more ambitious projects driven by human curiosity, to explore the unknown and comprehend our place in the vast senseless space. The Australian federal government in 2016-17 provided AUD 10 billion in support of science research and experiment development while NASA and ESA combined, plans to invest USD 25+ billion in 2017. Why is it important for governments to spend substantial amounts of money in fundamental science research? What are the benefits for the average tax payer, from governments investing billions of dollars into space science? How has our everyday lives been influenced by such investments? Together we shall discuss and explore how our investments in science has improved our way of living, and what the future may hold in store for us. Pre…
The ancients considered the Universe unchanging, and had a special name for the planets, which they regarded as “wanderers”. Any changes in the night sky were seen as portents of doom – and a reason to fear the Gods. The advent of modern astronomy means that we no longer fear changes in the night sky, indeed some of us make our living from them!
In this lecture I will tell you the story of the modern transient sky, where stars live and die in spectacular explosions and amazing instruments such as the LIGO and Virgo gravitational wave interferometers probe the darkest depths of the Universe. The discovery of gravitational waves was awarded the Nobel Prize in Physics this month and has the power to reveal a plethora of new science from the merger of black holes and other exotic stars. Presented on Friday 20 October 2017.