Skip to main content
Centres and institutes_

Sydney Institute for Astronomy

Cutting-edge theoretical and observational research
We are a leader in big data science with local and national supercomputing resources supporting simulations of cosmology, galaxy formation and evolution.

Our aims

Established within the School of Physics, the Sydney Institute for Astronomy (SIfA) is a national and international leader in astronomy and physics research. We are also committed to excellence in postgraduate training and research-led undergraduate training.

The University owns the:

  • Molonglo Observatory Synthesis Telescope (MOST)
  • Square Kilometre Pathfinder (SKAMP)

The development and application of new technology for the next generation of instruments and telescopes is enabled through state-of-the-art Sydney Astrophotonic Instrumentation Laboratories (SAIL).

Our Institute has leadership or key involvement in several major surveys including the:

  • Kepler K2 survey
  • Galactic Archaeology (GALAH) survey of a million nearby stars
  • SAMI Galaxy Survey
  • OzDES galaxy survey
  • FLASH survey of radio galaxies
  • UTMOST survey of fast radio bursts.

The CAASTRO Centre of Excellence is housed within the School of Physics and engages about half of the students and staff within SIfA. Through our leading role in the Physics Equity and Access Committee (PEAC), we aim to provide an environment that is equitable and supportive for all staff and students, free of conscious and unconscious bias, with access to facilities, learning and work open to all.

Facilities

We also have access to a number of astronomy facilities.

Research

We undertake research in several key areas:

Solar flares

Our recent work on flares includes the construction of a model for particle acceleration in flares based on inertial Alfven waves, which attempts to account for the flare 'number problem' - the difficulty in reconciling the large inferred numbers of accelerated electrons in flares with the low density of the background solar plasma.

For more information contact Mike Wheatland or Don Melrose.

Discovering exoplanets

Despite the recent avalanche of discovery, the exoplanetary systems discovered by Astronomy's newest field have so far raised far more questions than they have answered. To get a more representative picture of exoplanetary populations, including greater sensitivity to those in the habitable zone, we need new techniques to illuminate the unknown areas beyond the reach of our present instruments.

Researchers at SIfA have very strong linkages with NASA's Kepler mission and we are also engaged in opening entirely new windows onto the planetary realm, including advanced projects in both the optical and the radio attempting to capture the faint signals betraying the presence of a planet against the noise and glare of their host star.

For more information contact Peter TuthillTim Bedding or Tara Murphy.

Among the most fundamental areas underpinning of the entire field of astronomy is a quantitative understanding of the basic properties of stars. In recent years, observational astronomy has developed new technologies to deliver exquisite new studies of stellar surfaces, their immediate surroundings, and even probes of their interior structure. By revolutionising our view of the stars themselves, we are able to see the interplay between them and the galaxies that host them, the families of planets that they harbor, and the extreme physics of the weird remnants left behind after they die.

We host one of the world's leading asteroseismology groups and are pioneers in the use of the highly complementary technology of high resolution interferometry. The information obtained from using both atereoseismology and interferometry combined can help us study fascinating physics under the extreme conditions in stars such as mapping their internal rotational profile and from that the transport of angular momentum as they grow old. This combined approach turns out to be a particularly powerful way to gain a nearly complete observationally-based physical understanding of a star, for the first time free from simplifying assumptions and model parameters derived from theory.

For more information contact Tim Bedding or Peter Tuthill.

Magnetic fields and turbulence

Magnetism plays a critical role in many areas of astrophysics, because it controls both the bulk flow properties of interstellar gas as well as the motion of individual charged particles. However, we know surprisingly little about the properties of the Galactic magnetic field. We are making a concerted effort to redress this situation, using the Faraday rotation of the diffuse polarised radio background as a new way to study structure and turbulence in magnetized gas.

Some of our current projects include:

  • using the power spectra of rotation measures to map the turbulent cascade of ionised gas in the Galactic plane
  • using the Faraday rotation of background point sources to map out the large-scale magnetic structure of the inner Galaxy
  • analysing polarisation data on the Large Magellanic Cloud in order to carry out the most detailed study yet of the magnetic field of an external galaxy. 

Such data represent a whole new way of studying the ISM, and can allow a comprehensive study of interstellar magnetic fields on scales ranging from sub-parsec turbulence up to global galactic structure. 

Galactic structure

What can we learn about the formation processes of galaxies from studying the present structure of our own Milky Way, and nearby galaxies? Members of our group participate in international collaborations to observe structures in the outskirts of both the Milky Way and the Andromeda galaxies, thought to be remnants of interactions with smaller systems. Combining such observations with numerical simulations is an effective way for galaxy formation and evolutionary models to be tested. 

Galactic cannibalism occurs throughout the universe but, close to home, small dwarf galaxies are torn apart by the much more massive Milky Way and Andromeda Galaxy. Using telescopes from around the world, including the 10-m Keck telescope in Hawaii, we have mapped the tell-tale signs of tidal disruption and destruction, providing important clues to how large galaxies have grown over time. 

For more information contact Geraint Lewis.

Interstellar scintillation

The twinkling of stars, called scintillation, is due to fluctuations in the density of the air along the line of sight through the earth's atmosphere. Point-like radio sources, such as pulsars and quasars, also scintillate due to fluctuations in the electron density along the line of sight through the interstellar medium. Scintillation can lead to a change in the intensity of the source, a change in its apparent position, or both. 

Jean-Pierre Macquart and Don Melrose have developed a model for scintillations of radio sources based on scattering by discrete structures in the interstellar medium. This differs from the usual model that assumes a statistical fluctuation in density. Their approach was motivated by the thought that the rather large discrete structures required to explain Extreme Scattering Events (ESEs) may be extreme examples of a range of discrete structures common in the ISM. 

For more information contact Don Melrose.

Supernova remnants

We don't yet fully understand how stars explode and constraints on the many complicated processes which occur during core collapse are desperately needed. Since we rarely see a nearby star go supernova, our focus is on studying the aftermaths of supernova explosions, namely supernova remnants and young neutron stars, and in using these objects to infer the properties of the supernova, the progenitor star, and their surroundings.

This work is providing new insights into the micro- and macro-physics of the core-collapse process, on the properties of supernova progenitors, and on the mechanisms which produce the diversity we see in the resulting compact objects. 

For more information contact Anne GreenDick Hunstead or Tara Murphy.

Near field cosmology

This research aims to place the nearest galaxies, members of the Local Group, within a cosmological context. A physical model is being developed describing the formation and evolution of the Local Group, with attention to radiative and gaseous processes, combining radiative hydrodynamics code with multiwavelength data.

For more information contact Joss Bland-Hawthorn

The role of super-massive black holes

We are building large data-sets containing thousands of quasars and radio galaxies with the express aim of measuring how they evolve and what the physical processes are which drive the evolution. We can do this by studying how individual sub-populations evolve, what their environments are and the how the black holes interact with their host galaxy. We will build on this with a broad range of multi-wavelength observations (from X-ray to radio) using state-of-the-art astronomical facilities in Australia and overseas. 

For more information contact Scott CroomDick Hunstead or Elaine Sadler.

Galaxy formation and evolution

The multi-parameter nature of galaxy formation has meant that much progress has been made over the last decade by conducting massive surveys of up to one million galaxies to be constructed. These have, in turn, allowed detailed statistical analyses to be made, where the correlation between the multitudes of physical parameters can be studied.

All of these major surveys use a single optical fibre to collect the light from each galaxy. Yet, galaxies are intrinsically complex, multi-component systems with multiple structural components (eg. disks, bulges, halos) and elaborate interactions between the dark matter, stars, gas and super-massive black holes they contain. The use of single apertures thus loses valuable information and adds confusing biases.

We are leading the SAMI Galaxy Survey to survey thousands of galaxies in 3D measuring the way gas and stars move with these galaxies as well as where star formation is currently ongoing and how and why accretion onto super-massive black holes is important. Key questions we hope to answer include:

  • How does a galaxy’s environment influence its evolution? 
  • How does gas get into and out of galaxies? 
  • How is mass and angular momentum built up in galaxies?

The University of Sydney is also a key partner in new deep spectroscopic surveys such as the Galaxy And Mass Assembly (GAMA) project. This aims to get redshifts for hundreds of thousands of galaxies and combine this with multi-wavelength data to understand how galaxies are distributed and grouped within dark matter halos and measure the structural properties of galaxies.

For more information contact Scott Croom or Joss Bland-Hawthorn.

Gravitational lensing

Gravitational lensing is the bending of light by the gravitational field of a massive object. This phenomenon has a variety of astronomical applications. For example, it can be used as a natural telescope, magnifying distant sources into view or to probe the density profile of galaxies and galaxy clusters, testing dark matter theories.

The related field of microlensing has been used to search for low mass extrasolar planets, and to investigate the structure of quasars. Members of our group carry out computer simulations and observations of gravitational lensing.

Quasars, also known as quasi-stellar objects or QSOs, are luminous objects that are so distant that they appear pointlike in our images. When they are gravitationally lensed by an intervening galaxy, they can be multiply imaged. Often, assuming that the lens has a smooth mass distribution is adequate. However, in reality, galaxies are composed of stars and other compact objects, and are lumpy on small scales. Amazingly, this can actually change the brightnesses of the images, and these can vary with time in rather funky ways. We investigate these phenomena through the use of computational simulations.

For more information contact Geraint Lewis.

Dark energy

The WiggleZ team is using the Anglo-Australian Telescope to construct a huge redshift survey of ~400,000 galaxies at redshifts z~0.5-1.3.

The goal of this survey is to measure the "equation of state" of dark energy at high redshift. This is done by making high-precision measurements of the clustering of galaxies which ought to reveal the baryon acoustic oscillations (BAOs or baryon wiggles), a relic feature from the primordial Big Bang.

This encodes a fundamental physical scale whose size we can measure from the cosmic microwave background. Measuring this standard ruler at z=0.75 will give us the first high-precision measurement of dark energy independent of previous supernovae determinations. 

For more information contact Scott Croom.

Fundamental general relativity and cosmology

The theory of General Relativity is close to 100 years old and has been the preferred theory of gravity since its formulation by Einstein. Despite this, the understanding of General Relativity is not as advanced as might be expected, with few formal solutions existing and the physical interpretation of some of the mathematical results being unclear.

The Gravitational Astrophysics group conducts research into fundamental concepts in GR including the meaning and nature of expanding space and accelerated paths into black holes.

For more information contact Geraint Lewis.

Numerical cosmology

Members of our group study the implications of various dark energy models, primarily through N-body simulations, in order to increase the theoretical understanding of dark energy physics required in order to maximise the effectiveness of future surveys and instruments.

For more information contact Geraint Lewis.

Visit the Astrophotonics Research Group page for information.

Our people

Name Research Topic
Eromanga Adermann Cosmic Voids in Evolving and Interacting Dark Sector Cosmologies
Rebecca Brown Next generation 3D spectroscopy for the Anglo-Australian Telescope
Filip Chatys Period-luminosity relations of red giants and supergiants
Isabel Colman Asteroseismology using Kepler pixel data, with a focus on binary phenomena and red giants
Douglas Compton Asteroseismology of Red Giant Stars
Jason Drury Asteroseismology of Open Clusters: Ensembles and Kepler
Marcin Glowacki Study of HI Absorption Against Distant Radio Sources through ASKAP
Asger Gronnow The effect of the Galactic magnetic field on the accretion and survival of gas clouds
Daniel Hey Binaries and pulsating stars
Stuart Holwell  
Nikolas Iwanus Dark Matter Annihilation in Cosmological Simulations
Ben Jelliffee  
Apsem Jibrail The Growth of Angular Momentum in Non-Standard Cosmological Models
Shourya Khanna  
Alexey Latyshev Interferometric image recovery in astronomy
Gang Li Asteroseismology of gamma Doradus stars
Ralph Morgan High angular resolution imaging of Galactic microquasar SS 433 and various stellar objects
Angela Ng  
Harry Qiu Detection and classification of Fast Radio Bursts
Mohammad Rafat  
Katazhyna Redzikultsava Testing Non-Standard Cosmological Models With Supernova Data 
Kathy Ross  
Mathew Varidel  
Zhen Wan Galaxy Archeology
Troy Whinray  
Jie Yu Asteroseimology of 16,000 oscillating red giants observed by Kepler
Rai Yuen  
Andrew Zic  

Our events

Seminars are held weekly typically on Fridays at 11am to 12pm in LT5 at the School of Physics building (A28). If you wish to give a talk or presentation please email Jesse van de SandeApsem Jibrail, or Shourya Khanna.

Unfortunately, we do not have general funds available to cover travel or accommodation costs. If you would like to give a talk or are scheduled at a time that you will be away please let us know ASAP. If you have students or visitors that are going to have interesting topics to talk about please dob them in. Let us know if you will be giving a long (45min) or short (20min) talk, so we can have either two short talks or one long talk each week.

Date

Time

Speaker

Title

Sept 7

11am

Mireia Montes (UNSW)

Exploring the fossil record of cluster assembly: the intracluster light
Sept 14 11am  Amri Wandel (HUJI) The prospects for detecting life on exoplanets in the JWST/TESS era
Sept 21 11am Barnaby Norris & Tiphaine Lagadec (USyd)  

Oct 5

11am

Bjoern Malte Schaefer (Heidelberg Uni)

(non)Gaussian lensing of a (non)Gaussian cosmic microwave background

Nov 9 11am  Laura Fissel (NRAO)  
Dec 7 11am Philippa Browning (Jodrell Bank Centre for Astrophysics, University of Manchester) Plasma heating and particle acceleration by magnetic reconnection in solar and stellar flares

 

The State of the Universe

Professor Brian Schmidt

5 June 2018

Nobel Laureate Professor Brian Schmidt looks at the Universe's vital statistics and what we do (and don't) know about the past, present and future.

Director

Profile shot of Professor Joss Bland Hawthorn
Professor Joss Bland-Hawthorn
Academic profile

Contact us

Fax
  • +61 2 9351 7726
Address
  • Physics Building Physics Road The University of Sydney Darlington 2006, NSW

Our location